INTERSTITIAL BRACHYTHERAPY IN SOFT-TISSUE SARCOMAS - THE TATA-MEMORIAL-HOSPITAL EXPERIENCE

Background: Soft tissue sarcomas are relatively rare tumors with an ag gressive natural history associated with a high propensity for local r ecurrence following conservative surgery. It accounts for 1.8% of all cancers seen at the Tata Memorial Hospital, Mumbai. Organ preserving s urgery and tumor bed brachytherapy have revolutionized the management of soft tissue sarcomas. Patients and Methods: One hundred and seventy -seven patients with histologically proven non-metastatic cases of sof t tissue sarcomas in the age group of 16 to 79 years (median 41 years) were treated at the Tata Memorial Hospital between January 1983 and D ecember 1992. One hundred and fifty-one patients who had completed a m inimum of 24 months of treatment were studied. There were 100 males (6 6%) and 51 females (33%). The majority had recurrent lesions (70.3%). Extremities were involved in 75% of patients. Spindle cell sarcoma was the major histologic variant (30%). The patients underwent function p reserving surgery and temporary afterloading Ir-192 tumor bed brachyth erapy with or without external radiotherapy. Results: In patients rece iving brachytherapy only, 25 out of 33 (75%) were locally controlled a fter a median follow-up of 30 months. After successful salvage of loca l failures the overall local control improved to 82%. Similarly in the patients who received both interstitial brachytherapy and external ir radiation, the local control rate after a median followup of 40 months was 71% which improved to 86% after successful salvage. The overall t reatment related complication rate was less than 1%. The only marginal ly significant prognostic factor for local control was tumor grade (p = 0.06). Conclusions: The sequential combination of limited surgery an d tumor bed brachytherapy with or without external radiotherapy has be en established as an effective alternative to more ablative procedures like amputation. Histologic grade has proven to be a significant fact or determining local control.