Table 1.
Radiotherapy protocols across participating institutions.
Fig 1.
Representative CT of PIF and corresponding RT dose distribution.
The arrow indicates the site of a PIF in the sacrum, as seen on CT. The RT dose distribution for the same patient is also shown, demonstrating that the fracture occurred within the high-dose irradiated field.
Fig 2.
Incidence of PIF after the end of RT for cervical cancer (N = 208).
The timing of PIF onset was analyzed in 59 patients who developed PIF. The x-axis represents the number of months following the completion of radiation therapy, and the y-axis shows the cumulative percentage of patients with PIF. A total of 81.4% of PIFs occurred within two years after completion of RT.
Fig 3.
Incidence of pelvic insufficiency fracture in each institution.
Among patients who developed pelvic insufficiency fracture (PIF), this figure shows when the PIF occurred in patients in each institution. The horizontal axis represents the month PIF occurred, and the vertical axis represents the percentage of PIFs. In Institution A and C, almost all patients developed PIF within 2 years after completion of RT, with no significant difference. On the other hand, in Institution B and D, patients developed PIF within 4 years after RT. (A) Institution A (N = 81) (B) Institution B (N = 56) (C) Institution C (N = 37) (D) Institution D (N = 34).
Table 2.
Baseline characteristics of patients with and without PIF.
Table 3.
Baseline characteristics of patients of each instituion.
Table 4.
Treatment characteristics of each institution.
Table 5.
Multivariate Cox regression analysis for PIF.