Postradiation Damage to the Pelvic Girdle in Cervical Cancer Patients: Is Intensity-Modulated Radiation Therapy Safer Than Conventional Radiation?

Abstract

Intensity-modulated radiation therapy (IMRT) is frequently utilized in the treatment of cervical cancer. Our study compared instances of pelvic fractures, osteonecrosis, and osteomyelitis posttreatment with conventional radiation therapy (RT) versus IMRT in patients with cervical carcinomas. Eighty-three patients primarily treated with IMRT were case matched with 83 historical control subjects treated with conventional RT. Pretreatment and posttreatment computed tomography scans were reviewed. Logistic regression analysis was utilized to examine the effects of treatment type (conventional RT vs IMRT) on the occurrence of posttreatment pelvic bony structure complications while adjusting for confounders. In the IMRT group, 3 (4%) of 83 patients developed posttreatment sacral fractures (median follow-up, 51 months). In the conventional RT group, there were 14 pelvic girdle complications (17%): 9 fractures, 2 cases of osteonecrosis, and 3 cases of osteomyelitis (median follow-up, 43.5 months; odds ratio, 4.49 for conventional vs IMRT groups, P = 0.01; 95% confidence interval, 1.4-14.1). In addition, there were 4 cases of posttreatment osteoporosis in the conventional RT group. All patients with complications in the IMRT group and 11 of 13 in the conventional RT group were symptomatic. Intensity-modulated radiation therapy is associated with a lower risk for pelvic girdle complications than conventional RT.