Retroperitoneal sarcoma: 25 years of experience with aggressive surgical treatment at the Institute of Oncology, Ljubljana.

BACKGROUND AND OBJECTIVES: Retroperitoneal sarcomas are rare malignant tumors with an aggressive course of disease and high local recurrence rate. Local disease is the main cause of death. A retrospective study was undertaken to evaluate the results of aggressive surgical treatment in a series of patients of primary and recurrent retroperitoneal sarcomas. PATIENTS AND METHODS: From 1975 to 2000, 155 patients with retroperitoneal tumors were operated on at the Institute of Oncology, Ljubljana. Patients with fibromatosis and children less than 16 years were excluded from further calculation. Out of the rest 139 patients, 102 patients had localized retroperitoneal sarcoma, and 37 patients had retroperitoneal sarcoma with distant metastases Leiomyosarcoma was the most common type of histology, followed by liposarcoma and schwannoma. Their referral status was as follow: 56 had primary sarcoma, 20 residual sarcoma after operation elsewhere and 26 already recurrent sarcoma. Our treatment approach was aggressive. We removed surgically primary tumor, recurrent sarcoma and metastases, whenever possible. To this end, we performed, 235 operations for retroperitoneal sarcomas on 139 patients (up to 8 operations on 1 patient).
RESULTS: Complete resection was done in 97 of 102 patients with localized sarcoma (resectability rate 95%); in 55 patients, R0 resection was made, in 42 patients, R1 resection, in 3 patients, debulking procedure, and in 2 patients biopsy alone. In 118, patients at least one organ was resected completely or partially en bloc with tumor. The 5-, 10-, and 15-year survivals of patients with localized sarcoma were 52%, 36%, and 22%, respectively. The 5-year survival of patients with metastases was 12% (P = 0.0002), the 5- and 10-year survival rates of patients with R0 resection were 75% and 64%, respectively, and of those with R1 resection, 25% and 8%, respectively (0 < 0.00001). High tumor grade was associated with poor survival. The 5-year local recurrence rate of patients with primary sarcoma and of those with locally recurrent sarcoma was 37% and 71%, respectively (P = 0.04). After the first local recurrence, the 5- and 10-year survival rates were 42% and 26%, after the second local recurrence 45% and 22%, after the third local recurrence 43% and 11%, and after the fourth local recurrence 51% and 17%, respectively.
CONCLUSION: Complete surgical resection without microscopic residuum and contamination is likely to offer the best chances for long-term survival. Until there are no other treatment modalities, aggressive surgery for recurrent sarcoma is recommended.