Pelvic bone complications following radiation therapy of gynecologic malignancies: clinical evaluation of radiation-induced pelvic insufficiency fractures.

OBJECTIVE: To investigate the incidence, clinical and imaging finding of insufficiency fractures (IF) of the female pelvis following radiation therapy. METHODS: We reviewed the radiation oncology records of 158 patients with gynecologic malignancies who underwent external beam radiation therapy of the whole pelvis between April 1993 and March 2004. All patients underwent computed tomography (CT) scan every 6 months in follow-up after radiation therapy and magnetic resonance imaging (MRI) and radionuclide bone scan were added when the patients complained of a pelvic pain. RESULTS: Eighteen of 158 patients (11.4%) developed IF in the irradiated field with a median interval of 6 months (range 3-51) from the completion of external beam radiation therapy. The cumulative incidence of symptomatic IF at 5 years calculated with Kaplan-Meyer methods was 13%. Median age of the patients who developed IF was 70 years (range 48-88), and all of them were postmenopausal. IF occurred in the sacloiliac joints, upper limb of pubic bone, acetabulum, sacral body and 5th lumbar vertebra. Twelve of 18 patients had multiple lesions and 8 had symmetric longitudinal fracture lines parallel to the sacroiliac joints. Avoidance of weight bearing by bed rest and analgesics provided good pain relief in all patients, although symptoms lasted from 3 to 20 months. CONCLUSIONS: Radiation-induced pelvic IF following radiation therapy for gynecologic malignancies were frequently observed in the postmenopausal patients within 1 year after external beam radiation therapy. Symmetric fractures of the both sacroiliac joints were the characteristic pattern of pelvic IF. Knowledge of characteristic imaging pattern of IF is essential in order to rule out the bone metastasis. Therapy recommendations are conservative with analgesics.

Chemoradiation therapy for cervical cancer: toxicity of concurrent weekly cisplatin.

PURPOSE: To retrospectively evaluate the toxicity of concurrent weekly cisplatin and radiation therapy (RT) for locally advanced cervical cancer. MATERIALS AND METHODS: Between April 2001 and December 2004, 21 consecutive previously untreated patients with locally advanced cervical cancer were treated with concurrent chemoradiation therapy (CCRT) at the Tokushima University Hospital. Clinical stages were II: 5, III: 15, IVA: 1. External beam radiation therapy (EBRT) was delivered with 10 MV X-rays, 2 Gy fraction per day; total dose to the whole pelvis was 50 Gy. Iridium-192 high-dose-rate (HDR) intracavitary radiation therapy was performed with 10-30 Gy (median, 24 Gy) targeted at point A. Concurrent chemotherapy consisted of cisplatin, administered weekly at a dose of 40 mg/m2 for patients who were younger than 65 years and 30 mg/m2 for those 65 years or over. A maximum single dose of cisplatin, up to 70 mg/body, was administered in 5 cycles during EBRT. RESULTS: A total of 86 cycles of cisplatin were administered to the 21 patients, with a median of 4 cycles (range, 2-5). Severe hematological toxicity occurred in 18 patients (86%), including grade 3 in 17 patients (81%) and grade 4 in one patient (4.8%). Moderate or severe gastrointestinal toxicity occurred in 11 patients (52%), including grade 2 in 10 patients (48%) and grade 3 in one patient (4.8%). The grades of hematological toxicity were significantly greater in the 40 mg/m2 group than in the 30 mg/m2 group. All of the patients who were administered 40 mg/m2 of cisplatin developed grade 3 or greater hematological toxicity, including one patient with grade 4 toxicity. In the 30 mg/m2 group, 3 of 10 patients developed less than grade 3 toxicity, and all patients completed radiation therapy without interruption. CONCLUSION: The incidence of severe acute hematological toxicity was significantly higher in this study than in previously reported randomized controlled trials (RCTs), especially in the group of 40 mg/m2 cisplatin. A dose of 30 mg/m2 of cisplatin was considered to be feasible in weekly cisplatin and radiation therapy.