Soft tissue sarcomas: radiation as a therapeutic option

There is continuing assessment to find the most effective management strategy for primary soft tissue sarcomas. The goal of treatment for any patient with malignant neoplasm is to provide a tumour-free survival without clinically appreciable treatment-related morbidity. For most adult patients, this currently is attempted by a combination of relatively conservative surgery and moderate dose of radiation. The concept being that radiation at dose levels of 50 to 60 Gy is adequate to inactivate the tumour cells which lie beyond the margins of a conservative resection, i.e., it replaces the resection of large volumes of normal tissue. Laboratory measurements of radiation sensitivity of cell lines derived from sarcomas of soft tissue tumours have shown that they are not radiation-resistant relative to the cell lines derived form epithelial tumours. Hence, there is no surprise the this combined modality approach has been demonstrated to be effective. The frequency of local control (85% to 90%) is at least as high as that combined by ablative surgery, but with much lesser decrement in functional and cosmetic status. Additionally, radiation at dose levels of about 75 Gy is effective in achieving worthwhile local control rates when administered against small sarcomas of the soft tissues, e.g. volumes of < or = 60 ml. Thus, for selected tumours, radiation alone does offer a reasonable option when surgery is not feasible for technical reasons or the patient is not operable for medical reasons. Available data do not indicate a clear advantage for adjuvant chemotherapy for this group of tumours. Trials are in progress to assess the efficacy of neo-adjuvant chemotherapy. We are conducting a phase II trial of MAID chemotherapy and radiation preoperatively; the results to date are superior to matched concurrently treated patients. For local therapy, high and approximately comparable local control rates are being reported for several approaches: radical compartmental resection for selected patients, surgery and postoperative radiation therapy, surgery and preoperative radiation treatment, resection and intraoperative placement of catheters for brachytherapy and intra-arterial adriamycin, radiation and resection. Our preferred approach for T 2, grades II-III sarcomas of the soft tissues is radiation prior to surgery. There are, however, no data on the functional and cosmetic status after treatment of patients whose sarcomas are of a specified site and volume for treatment by these diverse methods. This is a critically important question in the assessment of proper clinical role of each of these approaches.