Pelvic insufficiency fractures in cervical cancer patients treated with definitive chemoradiation: impact of dosimetric and clinical factors

Abstract Background The aim of this study was to investigate the correlation between clinical and dosimetric factors and the incidence of pelvic insufficiency fractures (PIFs) in patients with cervical cancer treated with radical radiotherapy (RT), with or without chemotherapy, and to identify dose constraints that may reduce this risk. Methodology We reviewed data from cervical cancer patients treated with pelvic external-beam RT at our institution between 2020 and 2023. For each patient, pelvic bone marrow (BM) was contoured and divided into three subsites: lumbosacral spine (LSBM), ilium (IBM), and lower pelvis (LPBM). Data on the volume of each region receiving 10, 20, 30, and 40 Gy (V10, V20, V30, and V40, respectively) and D mean were collected. Results A total of 202 patients were retrospectively analyzed. Of these, 36 patients (17.8%) developed PIFs in the treatment field, with most cases being asymptomatic. Our analysis indicates that V40 of the LPBM is the most significant dosimetric parameter. When combined with patient age, this parameter stratifies the risk of fracture development according to the V40 value, thereby accounting for the patient’s age in the risk assessment. Conclusion This preliminary study allowed us to identify the dose constraints to reduce the risk of PIF according to patient age. Further investigations are needed to confirm these findings by including these parameters in the planning process.