[Retroperitoneal sarcomas: 2. Surgical and complementary treatment]

Retroperitoneal sarcomas are often voluminous tumors which spread via diverse anatomic paths. The resulting difficult excision explains the high frequency of local or peritoneal recurrence (80% at 10 years). Controlled, complete wide surgical excision is essential as repeated local recurrence is the usual cause of death. The main prognostic factors are the quality and extent of the surgical excision, the histopathology grade, and the metastatic extension. Peroperative pathology is indispensable as no imaging method can provide a sure differentiation between benign and malignant retroperitoneal tumors. CT-scan and MRI are useful to assess extension of the sarcoma to neighboring organs. Surgical treatment should be well-controlled with resectability criteria established preoperatively. A pseudo-capsule limiting the tumor should not be considered as a sufficient safety margin. Extension to neighboring organs is an essential element in preventing the risk of local recurrence. This extension may necessitate associating different access routes. The vascular element must be carefully assessed due to the major problems of reconstruction encountered in subperitoneal tumors, particularly in women. The role of neo-adjuvant chemotherapy has not been well-determined but pre and postoperative chemotherapy protocols currently under investigation have shown objective response. Intraoperative or postoperative adjuvant radiotherapy is also under evaluation. Operated patients should be followed regularly as the risk of recurrence is high. Surgery is indicated for the treatment of recurrences with the best results being obtained after early detection. PET and FDG explorations may be useful for detecting recurrence early.