Table 1.
Previous reports of ANKL.
Table 2.
The clinical characteristics of ANKL, ENKTL and CLPD-NK, and of EBV+ and EBV- ANKL.
Table 3.
The laboratory characteristics of ANKL, ENKTL and CLPD-NK, and of EBV+ and EBV- ANKL.
Fig 1.
Morphological characteristics of ANKL.
(A-C) Large granular lymphocytes, large cells with oval or irregular nuclei and abundant cytoplasm, and coarse azurophilic granules that are clearly visible (red arrow; Wright-Giemsa-stained samples from patients 5, 11 and 36 showed at ×1000). (D, E) Bone marrow biopsy from an ANKL patient showing extensive infiltration of abnormal NK cells (red arrow, from patient 22) (picture E is an enlargement of picture D) (paraffin-embedded, hematoxylin-eosin stained sample from patient 32 showed at ×200,). (F) Double immunofluorescent staining of CD56 (green) and CD3 (red) showingCD56+/CD3- NK cells in one patient’s bone marrow (paraffin-embedded sample from patient 30showed at×400).(G-I) Immunohistochemical results from aberrant NK cells in bone marrow, with NKG2C (brown) positivity(90.5%) (G), NKG2A (brown) positivity (from an EBV+ patient with ANKL) (H) and NKG2Anegativity (from an EBV- patient with ANKL) (I)(paraffin-embedded samples from patient 27, 28 and 29 showed at ×400).
Fig 2.
Comparison of immunophenotypic characteristics among samples from different NK diseases and healthy control detected by flow cytometry.
(A) Abnormal NK cells from patients with ANKL (red P3 group) were separated from lymphocytes (dark blueP2 group)based on the abnormal expression of the CD45 antigen when aCD45/SSC gating strategy was used. In contrast, in the patients with ENKTL or CLPD-NK and in the healthy controls (purple cell group in P2 group), NK cells usually overlapped with lymphocytes (dark blue P2 group).(B) The NK cells from patients with ANKL could be separated based on aCD56bright (red cell group) and CD56dim (purple cell group) phenotype when a CD56 gating strategy was used. In contrast, in the patients with ENKTL or CLPD-NK and in healthy controls, the NK cells (purple cell group) did not show this phenomenon. (C) The immunophenotypes for the 3 NK cell diseases tested and the healthy controls shown with the extent of expression for each antigen. Abnormal NK cells in patients with ANKL had lower expression levels of CD16, CD57 and CD8 than those from the patients with ENKTL (p<0.05). The expression levels of CD16, CD57, KIR (CD158a/h, CD158b, CD158e), CD7 and CD8 in abnormal NK cells in from the patients with ANKL were significantly decreased compared to those measured in the patients with CLPD-NK; whereas CD56 and Ki-67 were markedly more strongly expressed in the patients with ANKL than in the patients with CLPD-NK.* p<0.05, ** p<0.01.
Fig 3.
Patients with ANKL had highly complex karyotypes and could be tracked by 18-FDG-PET/CT.
(A) Cytogenetic findings for patient 16, who had a hypotetraploid karyotype. (B) Cytogenetic findings of patient 18, who had a karyotype showing the loss of chromosome 22. (C) The 18-FDG-PET/CT result for patient 26 showed splenomegaly and internal lymphadenopathy with uniformly elevated metabolism, and the maximum SUV was 5.6. (D) Patient 26 showed non-uniformly elevated metabolism in the bone marrow, and the maximum SUV was 9.2.
Fig 4.
ANKL developed aggressively and had a low OS.
(A) Laboratory test results were monitored from the day of admission to the day of diagnosis for all three types of NK cells diseases. The significantly dynamic data reflected the rapid deterioration of the patients with ANKL compared to those with the other two disease types. * p<0.05, ** p<0.01. (B) Prognosis for the three evaluated NK cell diseases, as analyzed by the Kaplan-Meier method. The median OS for ANKL was 27 days (range, 2–1283 days), whereas that for ENKTL was 249 days (range,8–1300 days) and that for CLPD-NK was 360 days (range,180–1270 days). The mortality rate for ANKL, ENKTL, and CLPD-NK were 10.5%, 48.1% and 0% respectively. * p<0.05, ** p<0.01. (C) OS stratification by serum LDH level (＜1000 U/L vs≥1000 U/L) for the patients with ANKL, as analyzed by the Kaplan-Meier method. * p<0.05, ** p<0.01.