PONE-D-25-05871Long-term outcomes of combination therapy with stereotactic body radiation therapy and cryoablation for T1-2N0M0 non-small cell lung cancer with tumor size ≥2 cmPLOS ONE

Dear Dr. Nomori,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Jun 28 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Xing-Xiong An, M.D.

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Partly

Reviewer #3: Yes

Reviewer #4: Partly

Reviewer #5: Partly

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: I Don't Know

Reviewer #3: Yes

Reviewer #4: Yes

Reviewer #5: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

Reviewer #4: Yes

Reviewer #5: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #4: Yes

Reviewer #5: No

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The manuscript is claerly written, with figures supporting the findings. Please, clarify more precisely how internal margin was defined (lines 158-160) and explain the rationale for accepting a BED <100Gy.

Since bias related to observational and retrospective nature of the study is highlighted, it is bold to include a comparation with results of a prospective study on SBRT in the conclusion.

Moreover, I suggest emphazing the small size of cohort in the discussion.

Reviewer #2: Thank you for the opportunity to review this manuscript on the long-term outcomes of combined stereotactic body radiotherapy and cryoablation for NSCLC. This study is a retrospective descriptive study reporting long-term outcomes after combined stereotactic body radiotherapy and cryoablation for T1-T2N0 NSCLC. There are very few reports on a combined approach for the treatment of lung cancers or oligometastasis. While the approach is novel, several issues in this study need addressing to ensure scientific validity.

Major issues

1. Table 1: There is one patient with a T3 tumour (>5cm). If the inclusion is T1-T2, I am unsure why this patient was included. I suggest excluding T3 tumours.

2. A BED of at least 80 Gy will be considered low according to the current recommendation of at least 100 Gy, as outcomes tend to be poorer at doses less than 100 Gy. It would be beneficial to discuss the reasons why some tumours were treated with doses below 100 Gy. It is unclear whether the dose was reduced to facilitate combined treatment or to meet OAR dose constraints.

3. The follow-up CT scans ceased at three years (page 11, line 181), despite a median follow-up of 73 months. No information has been provided regarding the methods used to diagnose recurrences after this period.

4. Local recurrences were diagnosed either through needle biopsy or when “the primary site showed apparent increase” (page 12, line 208-9). Different patterns of fibrosis, including dense mass-like consolidation, can be observed after SBRT, making the criteria used in the study for radiologically diagnosing recurrence inadequate. It is necessary to provide a clear description of the criteria used for radiological diagnosis of recurrence when a needle biopsy was not performed, including the criteria used to select patients for needle biopsy and how radiation pneumonitis was differentiated from recurrence.

5. In the regression analysis of factors correlating with LC and survival, BED of SBRT should be included, since it has been shown to affect these outcomes.

6. It has been noted that the majority of SBRT studies do not report results beyond three years, which is accurate. However, RTOG 0915 and RTOG 0236 have presented 5-year outcomes, with LC rate of 89.4-93.2%, and RTOG 0618 presented a 4-year LC of 96%. The local control rates observed in these RTOG studies are comparable to those reported in this study. I suggest discussing the results within the context of the outcomes of the RTOG studies.

7. 24 out of 32 patients died due to "other disease" (page 15, line 248-9). The high rate of competing non-cancer mortality can diminish the incidence of cancer-related events, which has been an issue in comparing SBRT studies. It is essential to discuss how competing non-cancer mortality affects the assessment of treatment outcomes.

8. In the conclusion, it is inappropriate to suggest that combined treatment improved survival, as this is a single-arm cohort study without a comparison group. Furthermore, stating that the rates of adverse events were acceptable significantly understates the 38% incidence of pneumothorax requiring chest drainage and possibly hospitalisation. This incidence does not compare favorably with the low occurrence of adverse events observed following SBRT alone. Conclusions should take into account the significant limitations of the study.

9. Comparing Kaplan-Meier graphs for OS and DSS (Fig. 4 and 6), the number of patients at risk is nearly identical in both graphs. Given that 75% of the deaths were due to non-cancer causes, there should be a notable difference in the numbers at risk. The statistical analyses were performed using Excel, which I understand does not have a built-in Kaplan-Meier graph function and thus requires a third-party add-in or some manual steps. I recommend verifying the results using alternative statistical software.

Minor issues

1. T1-2 tumour with tumour size > 2cm as per 8th edition will be T1c-T2. I suggest using T1c-T2 instead of a lengthier description.

2. Abstract: The last line in the Methods (page 3, line 50), “Median follow-up duration was 73 months”, is a repetition since the median follow-up is mentioned in the first paragraph (line 42).

3. Table 1: The breakdown of T stage % adds up to only 91%.

4. Tables 3 and 4: the last column representing the cause of mortality is labelled “Prognosis, " which refers to the chance of an event happening. I suggest labelling it mortality and mentioning whether it is due to cancer or other causes for each patient.

5. The terms pneumonia and pneumonitis are used interchangeably to describe radiation pneumonitis. I suggest using radiation pneumonitis for consistency. This applies to tables 4 and 7 as well.

6. I suggest labelling Fig. 2 as a Consort flow diagram instead of “ patient algorithm”. Use terms such as assessed for eligibility, excluded, included in analysis, etc, to label each box clearly.

7. I suggest labelling the last subheading as Discussion rather than Comments.

8. There is use of the term “other disease” in several places, which I presume refers to a disease other than cancer. However, I am unsure if it excludes second cancers. This needs clarification.

Reviewer #3: Line 100-102: Sentence not clear.

Line 131-136: I don’t see any information on setting.

Line 135: Are those numbers in the brackets dates or what?

Line 146: What cut off was classified as old age?

Line 148-149: Did you have to test before determining if tumor was outside the reach of the probe?

Be consistent with the use of your terms. Mixing terms like local recurrence, survival, overall survival, local control makes it confusing.

Line 222: P≤0.15?? Why?

Line 233-236: Were there multiple reasons for participation? Numbers seem to exceed 66 by a lot.

Line 239 and 241: IQR should be checked.

Line 243: You followed some participants for 3 months. What happened if they were not lost to follow-up? Were they deceased?

Line 268: Is it the traditional p-value? Seems unusually large. Any justification for that?

Line 269: You set p value at 0.05, so why do you consider 0.09 significant

Line 282: What do you mean by comment?

You could explore the influence of patient’s prognosis on the outcomes. Poor prognosis can most likely after survival.

You need to provide a more thorough discussion for your findings.

Line 320-324: Don’t just state the limitations of the studies but proceed to provide suggestions for future steps.

Work on conclusion and make it better.

Reviewer #4: This study investigates a relatively uncommon treatment strategy—SBRT followed by cryoablation—for early-stage NSCLC patients who are ineligible for surgery. Reporting favorable 5-year outcomes in this population is noteworthy and clinically interesting, especially given the limited data available for this specific combination approach. The study’s strength lies in its long follow-up period and the effort to explore a minimally invasive option for patients who are not surgical candidates.

However, despite the clinical relevance and the encouraging outcomes, the lack of a control group, unclear patient selection criteria, and potential selection bias make it difficult to draw strong conclusions about the superiority or added benefit of the combined approach. The conclusions, as currently written, overstate the findings beyond what the data can support. Meaningful revisions to the manuscript are necessary to improve clarity, transparency, and scientific robustness.

- Justification for SBRT and Cryoablation Strategy

The rationale behind applying cryoablation after SBRT is not adequately justified. Authors suggest that OS might improve by preventing distant recurrence or eradicating residual tumor, but this hypothesis requires more mechanistic and clinical justification.

It is recommended that the Introduction and Discussion sections provide a more detailed and logically structured explanation of why this combination strategy was pursued. Ideally, this justification should be supported by relevant preclinical or clinical literature. Including references that explain potential synergistic effects or biological rationale would strengthen the scientific foundation of the study design.

- Patient Selection and Treatment Allocation

It is unclear how the treatment modality was determined among 333 patients. What were the specific indications for: Surgery, SBRT alone, Cryoablation alone, or SBRT followed by cryoablation. This ambiguity severely limits the interpretability of the study results and introduces significant selection bias.

For example, cryoablation could only be performed for “tumors located within the reach of the cryoprobe,” suggesting technical feasibility was a selection factor. This should be explicitly acknowledged and addressed as a source of bias.

- Need for Comparator Group

The study would benefit greatly from a matched SBRT-alone cohort to determine whether the additional cryoablation offers real benefit in terms of OS, LC, or adverse events. Without such a comparison, the claim that combination therapy is superior to SBRT alone is not supportable.

A statement like “SBRT followed by cryoablation improves survival compared to SBRT alone” (e.g., lines 60–63, 328–330) is speculative and not supported by direct comparison in this study. The study lacks a control group of patients receiving SBRT alone. Thus, the conclusion should be softened (e.g., “SBRT followed by cryoablation showed favorable outcomes…”).

- Patterns of Recurrence

It would significantly strengthen the paper to report patterns of recurrence (local, regional, or distant) and provide detail on subsequent treatments received, especially in recurrent cases.

- Toxicity Assessment

The distinction between bronchopneumonia (BP) and radiation pneumonitis (RP) is not clearly explained. What were the diagnostic criteria used to differentiate the two?

CTCAE version 4.03 is stated to be used in the main text, but Reference 17 refers to CTCAE v3.0, which should be corrected.

- Overuse of Figures and Tables

Consider combining Figures 3–6 into a single multipanel survival figure (e.g., Kaplan-Meier curves).

Tables 3–5 may be more appropriate as Supplementary Tables, as they do not add substantial value to the main narrative.

- Outdated References

Many references are more than a decade old. Recent data on SBRT, cryoablation, and combination therapies should be incorporated to better contextualize the study findings.

Reviewer #5: The manuscript presents a well-designed retrospective cohort study on the long-term outcomes of combined SBRT and cryoablation for cT1-2N0M0 NSCLC with tumor size ≥2 cm. The median follow-up of 73 months and focus on a clinically relevant population – patients ineligible or unwilling to undergo surgery – enhance the significance of this work. The results are clearly reported and show promising local control and overall survival outcomes.

However, several areas require clarification, elaboration, and improvement to strengthen the manuscript's scientific rigor and clinical impact. Please refer to the attached documents of suggested revision.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy .

Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

Reviewer #4: No

Reviewer #5: No

**********

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Attachments

Attachment

Submitted filename: RevGeneralComments.docx

Attachment

Submitted filename: renamed_22856_minorcomments.docx

<div>PONE-D-25-05871R1Long-term outcomes of stereotactic body radiation therapy followed by cryoablation using liquid nitrogen for stage I non-small cell lung cancer with tumor size ≥2 cmPLOS ONE

Dear Dr. Nomori,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Aug 17 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Xing-Xiong An, M.D.

Academic Editor

PLOS ONE

Additional Editor Comments:

Please provide point-by-point responses to each reviewer's comments, instead of just roughly putting all the answers together. 

For example:

Response to reviewer #1:

Comment 1:.....

Response 1:.....

Comment 2:.....

Response 2:.....

Comment 3:.....

Response 3:.....

……

Response to reviewer #2:

Comment 1:.....

Response 1:.....

Comment 2:.....

Response 2:.....

Comment 3:.....

Response 3:.....

……

Response to reviewer #3:

Comment 1:.....

Response 1:.....

Comment 2:.....

Response 2:.....

Comment 3:.....

Response 3:.....

……

Response to reviewer #4:

….

Response to reviewer #5:

….

Previous Comments from Reviewers:

Reviewer #1: The manuscript is claerly written, with figures supporting the findings. Please, clarify more precisely how internal margin was defined (lines 158-160) and explain the rationale for accepting a BED <100Gy.

Since bias related to observational and retrospective nature of the study is highlighted, it is bold to include a comparation with results of a prospective study on SBRT in the conclusion.

Moreover, I suggest emphazing the small size of cohort in the discussion.

Reviewer #2: Thank you for the opportunity to review this manuscript on the long-term outcomes of combined stereotactic body radiotherapy and cryoablation for NSCLC. This study is a retrospective descriptive study reporting long-term outcomes after combined stereotactic body radiotherapy and cryoablation for T1-T2N0 NSCLC. There are very few reports on a combined approach for the treatment of lung cancers or oligometastasis. While the approach is novel, several issues in this study need addressing to ensure scientific validity.

Major issues

1. Table 1: There is one patient with a T3 tumour (>5cm). If the inclusion is T1-T2, I am unsure why this patient was included. I suggest excluding T3 tumours.

2. A BED of at least 80 Gy will be considered low according to the current recommendation of at least 100 Gy, as outcomes tend to be poorer at doses less than 100 Gy. It would be beneficial to discuss the reasons why some tumours were treated with doses below 100 Gy. It is unclear whether the dose was reduced to facilitate combined treatment or to meet OAR dose constraints.

3. The follow-up CT scans ceased at three years (page 11, line 181), despite a median follow-up of 73 months. No information has been provided regarding the methods used to diagnose recurrences after this period.

4. Local recurrences were diagnosed either through needle biopsy or when “the primary site showed apparent increase” (page 12, line 208-9). Different patterns of fibrosis, including dense mass-like consolidation, can be observed after SBRT, making the criteria used in the study for radiologically diagnosing recurrence inadequate. It is necessary to provide a clear description of the criteria used for radiological diagnosis of recurrence when a needle biopsy was not performed, including the criteria used to select patients for needle biopsy and how radiation pneumonitis was differentiated from recurrence.

5. In the regression analysis of factors correlating with LC and survival, BED of SBRT should be included, since it has been shown to affect these outcomes.

6. It has been noted that the majority of SBRT studies do not report results beyond three years, which is accurate. However, RTOG 0915 and RTOG 0236 have presented 5-year outcomes, with LC rate of 89.4-93.2%, and RTOG 0618 presented a 4-year LC of 96%. The local control rates observed in these RTOG studies are comparable to those reported in this study. I suggest discussing the results within the context of the outcomes of the RTOG studies.

7. 24 out of 32 patients died due to "other disease" (page 15, line 248-9). The high rate of competing non-cancer mortality can diminish the incidence of cancer-related events, which has been an issue in comparing SBRT studies. It is essential to discuss how competing non-cancer mortality affects the assessment of treatment outcomes.

8. In the conclusion, it is inappropriate to suggest that combined treatment improved survival, as this is a single-arm cohort study without a comparison group. Furthermore, stating that the rates of adverse events were acceptable significantly understates the 38% incidence of pneumothorax requiring chest drainage and possibly hospitalisation. This incidence does not compare favorably with the low occurrence of adverse events observed following SBRT alone. Conclusions should take into account the significant limitations of the study.

9. Comparing Kaplan-Meier graphs for OS and DSS (Fig. 4 and 6), the number of patients at risk is nearly identical in both graphs. Given that 75% of the deaths were due to non-cancer causes, there should be a notable difference in the numbers at risk. The statistical analyses were performed using Excel, which I understand does not have a built-in Kaplan-Meier graph function and thus requires a third-party add-in or some manual steps. I recommend verifying the results using alternative statistical software.

Minor issues

1. T1-2 tumour with tumour size > 2cm as per 8th edition will be T1c-T2. I suggest using T1c-T2 instead of a lengthier description.

2. Abstract: The last line in the Methods (page 3, line 50), “Median follow-up duration was 73 months”, is a repetition since the median follow-up is mentioned in the first paragraph (line 42).

3. Table 1: The breakdown of T stage % adds up to only 91%.

4. Tables 3 and 4: the last column representing the cause of mortality is labelled “Prognosis, " which refers to the chance of an event happening. I suggest labelling it mortality and mentioning whether it is due to cancer or other causes for each patient.

5. The terms pneumonia and pneumonitis are used interchangeably to describe radiation pneumonitis. I suggest using radiation pneumonitis for consistency. This applies to tables 4 and 7 as well.

6. I suggest labelling Fig. 2 as a Consort flow diagram instead of “ patient algorithm”. Use terms such as assessed for eligibility, excluded, included in analysis, etc, to label each box clearly.

7. I suggest labelling the last subheading as Discussion rather than Comments.

8. There is use of the term “other disease” in several places, which I presume refers to a disease other than cancer. However, I am unsure if it excludes second cancers. This needs clarification.

Reviewer #3: Line 100-102: Sentence not clear.

Line 131-136: I don’t see any information on setting.

Line 135: Are those numbers in the brackets dates or what?

Line 146: What cut off was classified as old age?

Line 148-149: Did you have to test before determining if tumor was outside the reach of the probe?

Be consistent with the use of your terms. Mixing terms like local recurrence, survival, overall survival, local control makes it confusing.

Line 222: P≤0.15?? Why?

Line 233-236: Were there multiple reasons for participation? Numbers seem to exceed 66 by a lot.

Line 239 and 241: IQR should be checked.

Line 243: You followed some participants for 3 months. What happened if they were not lost to follow-up? Were they deceased?

Line 268: Is it the traditional p-value? Seems unusually large. Any justification for that?

Line 269: You set p value at 0.05, so why do you consider 0.09 significant

Line 282: What do you mean by comment?

You could explore the influence of patient’s prognosis on the outcomes. Poor prognosis can most likely after survival.

You need to provide a more thorough discussion for your findings.

Line 320-324: Don’t just state the limitations of the studies but proceed to provide suggestions for future steps.

Work on conclusion and make it better.

Reviewer #4: This study investigates a relatively uncommon treatment strategy—SBRT followed by cryoablation—for early-stage NSCLC patients who are ineligible for surgery. Reporting favorable 5-year outcomes in this population is noteworthy and clinically interesting, especially given the limited data available for this specific combination approach. The study’s strength lies in its long follow-up period and the effort to explore a minimally invasive option for patients who are not surgical candidates.

However, despite the clinical relevance and the encouraging outcomes, the lack of a control group, unclear patient selection criteria, and potential selection bias make it difficult to draw strong conclusions about the superiority or added benefit of the combined approach. The conclusions, as currently written, overstate the findings beyond what the data can support. Meaningful revisions to the manuscript are necessary to improve clarity, transparency, and scientific robustness.

- Justification for SBRT and Cryoablation Strategy

The rationale behind applying cryoablation after SBRT is not adequately justified. Authors suggest that OS might improve by preventing distant recurrence or eradicating residual tumor, but this hypothesis requires more mechanistic and clinical justification.

It is recommended that the Introduction and Discussion sections provide a more detailed and logically structured explanation of why this combination strategy was pursued. Ideally, this justification should be supported by relevant preclinical or clinical literature. Including references that explain potential synergistic effects or biological rationale would strengthen the scientific foundation of the study design.

- Patient Selection and Treatment Allocation

It is unclear how the treatment modality was determined among 333 patients. What were the specific indications for: Surgery, SBRT alone, Cryoablation alone, or SBRT followed by cryoablation. This ambiguity severely limits the interpretability of the study results and introduces significant selection bias.

For example, cryoablation could only be performed for “tumors located within the reach of the cryoprobe,” suggesting technical feasibility was a selection factor. This should be explicitly acknowledged and addressed as a source of bias.

- Need for Comparator Group

The study would benefit greatly from a matched SBRT-alone cohort to determine whether the additional cryoablation offers real benefit in terms of OS, LC, or adverse events. Without such a comparison, the claim that combination therapy is superior to SBRT alone is not supportable.

A statement like “SBRT followed by cryoablation improves survival compared to SBRT alone” (e.g., lines 60–63, 328–330) is speculative and not supported by direct comparison in this study. The study lacks a control group of patients receiving SBRT alone. Thus, the conclusion should be softened (e.g., “SBRT followed by cryoablation showed favorable outcomes…”).

- Patterns of Recurrence

It would significantly strengthen the paper to report patterns of recurrence (local, regional, or distant) and provide detail on subsequent treatments received, especially in recurrent cases.

- Toxicity Assessment

The distinction between bronchopneumonia (BP) and radiation pneumonitis (RP) is not clearly explained. What were the diagnostic criteria used to differentiate the two?

CTCAE version 4.03 is stated to be used in the main text, but Reference 17 refers to CTCAE v3.0, which should be corrected.

- Overuse of Figures and Tables

Consider combining Figures 3–6 into a single multipanel survival figure (e.g., Kaplan-Meier curves).

Tables 3–5 may be more appropriate as Supplementary Tables, as they do not add substantial value to the main narrative.

- Outdated References

Many references are more than a decade old. Recent data on SBRT, cryoablation, and combination therapies should be incorporated to better contextualize the study findings.

Reviewer #5: The manuscript presents a well-designed retrospective cohort study on the long-term outcomes of combined SBRT and cryoablation for cT1-2N0M0 NSCLC with tumor size ≥2 cm. The median follow-up of 73 months and focus on a clinically relevant population – patients ineligible or unwilling to undergo surgery – enhance the significance of this work. The results are clearly reported and show promising local control and overall survival outcomes.

However, several areas require clarification, elaboration, and improvement to strengthen the manuscript's scientific rigor and clinical impact. Please refer to the attached documents of suggested revision.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #2: (No Response)

Reviewer #3: (No Response)

Reviewer #5: (No Response)

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #5: Partly

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #2: Yes

Reviewer #3: No

Reviewer #5: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #2: Yes

Reviewer #3: No

Reviewer #5: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #5: No

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #2: A point-by-point response to all the reviewer comments has not been provided. Severe issues I raised have not been addressed and remain unresolved.

Reviewer #3: Other commnets seem to have been addressed. I do not see any of my comments provided earlier addressed. 

Reviewer #5: Thank you for the opportunity to review this revised manuscript entitled “Long-term outcomes of stereotactic body radiation therapy followed by cryoablation using liquid nitrogen for stage I non-small cell lung cancer with tumor size ≥2 cm.”

I commend the authors for their thorough revision in addressing the reviewers’ previous comments and for the scientific merit of this study, which explores an important combination therapy approach for early-stage NSCLC. The manuscript demonstrates solid scientific content, with clear objectives and appropriate methodology.

However, I note that the manuscript does not yet fully meet journal writing standards in terms of its scientific writing presentation. Specifically:

• Tables and figures are cited within the text but lack adequate integration and explanation. Standard journal writing requires that each table and figure is not only referenced but also introduced with context, summarised with key findings, and interpreted within the Results and Discussion. Currently, many citations simply direct the reader to the figure or table without providing an explanation of its relevance or implications.

• Despite native revision, the language and grammar remain awkward in several sections, with phrasing that may impede clarity for an international readership. Further professional language editing is required to ensure fluency, precision, and consistency.

• The results presentation tends to read as raw data reporting rather than a scientific narrative, which is expected in journal publications to guide readers through the study findings and their implications systematically.

I recommend major language editing and revision of the Results and Discussion sections, with attention to:

• Introducing each table and figure with purpose.

• Explaining what each demonstrates.

• Interpreting how each finding addresses the study objectives and contributes to the field.

Overall, I believe that with these revisions, the manuscript will reach the presentation standards required for publication and effectively communicate its important findings to the wider oncology and radiology community.

Editor Notes: Please address two rounds of concerns of Reviewer #5 at the same time (previous and current questions).

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy .

Reviewer #2: No

Reviewer #3: No

Reviewer #5: No

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[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/ . PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org . Please note that Supporting Information files do not need this step.

Attachments

Attachment

Submitted filename: Re-revised_comments.docx

PONE-D-25-05871R2Long-term outcomes of stereotactic body radiation therapy followed by cryoablation using liquid nitrogen for stage I non-small cell lung cancer with tumor size ≥2 cmPLOS ONE

Dear Dr. Nomori,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Sep 26 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Xing-Xiong An, M.D.

Academic Editor

PLOS ONE

Journal Requirements:

If the reviewer comments include a recommendation to cite specific previously published works, please review and evaluate these publications to determine whether they are relevant and should be cited. There is no requirement to cite these works unless the editor has indicated otherwise. 

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #3: All comments have been addressed

Reviewer #5: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #3: Yes

Reviewer #5: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #3: Yes

Reviewer #5: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #3: No

Reviewer #5: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #3: Yes

Reviewer #5: No

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #3: (No Response)

Reviewer #5: Thank you for your submission and for the thoughtful revisions made in response to prior feedback. Your study presents a novel and clinically relevant approach by combining stereotactic body radiation therapy (SBRT) with cryoablation for stage I non-small cell lung cancer (NSCLC) with tumors ≥2 cm. The long-term follow-up and outcome data are valuable and contribute meaningfully to the literature, particularly in addressing the limitations of SBRT or ablation alone in this patient population.

The manuscript demonstrates scientific merit and methodological rigor. The rationale for the combination therapy is well-articulated, and the authors have made commendable efforts to clarify the study design, patient selection, and treatment protocols.

However, I must respectfully note that the overall language and writing style remain below the standard typically expected for publication in a scientific journal. Despite revisions, the manuscript still contains awkward phrasing, grammatical inconsistencies, and structural issues that affect clarity and readability. These issues may hinder the accessibility and impact of your findings for an international readership.

I encourage the authors to consider a thorough professional language edit to improve the manuscript’s fluency, coherence, and scientific tone. Doing so would better reflect the quality of the research and enhance its suitability for publication.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy .

Reviewer #3: No

Reviewer #5: No

**********

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/ . PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org . Please note that Supporting Information files do not need this step.

Long-term outcomes of combination therapy with stereotactic body radiation therapy plus cryoablation using liquid nitrogen for stage I non-small cell lung cancer with tumors ≥2 cm

PONE-D-25-05871R3

Dear Dr. Nomori,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager®  and clicking the ‘Update My Information' link at the top of the page. For questions related to billing, please contact billing support .

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Xing-Xiong An, M.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Thanks for the authors' efforts to comprehensively improve your manuscript according to editor's and reviewers' comments. I am pleased to inform you that your paper can be accepted for publication now. Thanks for the chance to assess your work. Additionally, many thanks for all the reviewers' precious inputs.

Reviewers' comments: