Clinical impact of extended field radiation therapy in Stage III carcinoma cervix versus conventional field techniques: A comparative study.

Aim: The aim of the study was to examine tumor control and clinical outcomes of extended field irradiation and compare it with those treated with conventional field in same disease profile and also to determine toxicities associated with radiation treatment.

Methods: This study included 50 biopsy-proven and registered International Federation of Gynecology and Obstetrics Stage III cases of carcinoma cervix treated with concurrent computed tomography (injection cisplatin 40 mg/m weekly) + external beam radiotherapy (EBRT) upto 50 Gy + high-dose-rate intracavitary brachytherapy (ICBT) (22.5 Gy). Twenty-five patients were randomized to each arm. Arm A: Conventional field EBRT 50 Gy with concurrent weekly chemotherapy followed by ICBT. Arm B: Extended field EBRT 50 Gy with concurrent weekly chemotherapy followed by ICBT.

Results: At 12-month follow-up, 43 patients (86%) had attained CR. Overall, seven patients (14%) were in noncomplete response (CR) group (non-CR = patients with partial response, stable disease, or progressive disease). The non-CR rate was 16% for Arm A and 20% for Arm B. Among seven patients of non-CR group, six had local disease and one had failure at distant site. Five (10%) patients died in this study, 2 (8%) in Arm A and 3 (12%) patients in Arm B. Residual disease was seen in 2 (4%) patients. Grade III diarrhea was seen in eight patients (16%), 3 in Arm A (12%) and 5 in Arm B (20%). Fifteen patients (30%) developed Grade III skin toxicity. Seven patients in Arm A (28%) and 8 patients (32%) in Arm B developed Grade III toxicity. Twenty-five (50%) cases presented with varying stages of vaginal adhesions and stenosis.

Conclusion: Majority of patients achieved CR with minimal acute and late toxicities with similar results in both arms. No patient had pelvic or para-aortic metastasis until recent follow-up.