Pelvic Insufficiency Fractures after Chemoradiation for Gynecologic Malignancies: A Review of Seven Cases

Abstract

Background: Radiation-induced pelvic insufficiency fracture (PIF) is an important complication associated with pelvic radiation therapy (RT) for patients with gynecologic malignancies. Despite known risk factors and recent reports describing the incidence on the order of 30 percent, there has been a dearth of translational research or consensus statements to guide clinical management. Objective: The aim of this study is to describe seven cases of PIF diagnosed and managed at the Massachusetts General Hospital during a 5-year period and to perform a focused review of the literature to inform several clinical questions that remain unanswered. A secondary aim of this study is to highlight the need for additional research related to screening, prophylaxis, diagnostics, and treatment of PIF in patients with gynecologic malignancy. Methods: In the current retrospective review, we report 10 cases of PIF diagnosed over a 5-year period in 7 patients with vulva r (4), vaginal (2), and cervical (1) cancer following chemoradiation therapy at a single institution. Data w ere collected from the medical records by a single investigator and all diagnostic imaging was reviewed by a single radiologist to confirm the presence or absence of PIF. Results: All 7 patients were post-menopausal and received concurrent chemoradiation, 3 were over the age of 65 years old (42.8%), 3 had BMI < 25 kg/m 2 (42.8%), 2 had a history of osteoporosis (28.6%), and 1 had a history of hormone replacement therapy use (14.3%). No patients underwent standard screening for PIF and no patients were started on prophylaxis prior to diagnosis. The plain film was the most common initial imaging performed while MRI was the most common overall study used to diagnose PIF. Median time to the development of fracture was 16 months (range 4 - 114) with femoral neck fracture being the most common (40%) and sacral fractures trailing close behind (30%). 7 of 10 fractures were initially managed expectantly with 1 ultimately failing expectant management and requiring surgical intervention. 4 of 10 fractures required surgical intervention. All patients had resolution of symptoms by 12 months after diagnosis. Conclusion: Radiation-induced PIF remains an important complication associated with pelvic RT. Significant risk factors have been identified and studies have compared various diagnostic imaging modalities. Future studies are needed to compare screening algorithms and evaluate the comparative effectiveness of prophylactic pharmacotherapies. Future studies are also needed to determine the cost-effectiveness of PET/CT versus MRI and compare the morbidity associated with expectant management versus surgical intervention in patients with symptomatic fractures .