Retroperitoneal soft-tissue sarcomas: prognosis and treatment of primary and recurrent disease.

Soft-tissue sarcomas of the retroperitoneum constitute a heterogeneous group of tumors with varying histology, potential for complete resection, and propensity for recurrent disease-making the development of effective treatment difficult and challenging. A retrospective review of 23 patients with retroperitoneal sarcomas from 1985 through 1998 was performed to assess the biological behavior and clinical outcomes and to identify factors that may influence prognosis and optimize treatment strategy. Liposarcomas were the most common pathology (61%); 79 per cent of these were of low grade. Leiomyosarcomas were the next most common pathology (30%); 43 per cent of these were of low grade. Low-grade sarcomas overall accounted for 62 per cent of the total group. Low-grade tumors independent of histologic type exhibited good prognosis for long-term survival with a median survival of 44 months. In contrast, intermediate- or high-grade tumors were associated with a median survival of only 9 months (P < 0.02). On the other hand, tumor histologic type independent of grade did not have a significant survival difference. Complete tumor resection was possible in 21 of 23 patients, which gives an overall resectability rate of 91 per cent. Eight patients (36%) remain disease-free after initial surgical treatment. However, local recurrence was common; this occurred in 11 of 22 patients (50%). Local recurrence, however, did not preclude long-term survival. Surgical resection of recurrent disease was done in nine patients with a median survival of 91 months (range 24-150 months). Three patients had as many as three operations for recurrent disease. With subsequent recurrences there was a decrease in interval from approximately 4 years to 2 years, and 33 per cent of these patients developed tumor dedifferentiation to high grade. An aggressive surgical approach with reoperation can produce prolonged survival in patients with low-grade retroperitoneal sarcoma.