Resectable retroperitoneal soft tissue sarcomas. The effect of extent of resection and postoperative radiation therapy on local tumor control.

BACKGROUND

Soft tissue malignancies of the retroperitoneum are rare. Surgery is commonly considered the first choice of treatment. There is still no consensus concerning the precise value of the extent of surgery and the value of additional treatment modalities.

METHODS

From 1973 to 1990, 34 patients were initially treated by surgery for retroperitoneal soft tissue sarcomas at the Netherlands Cancer Institute. In a retrospective study, the prognostic effect of extent of primary surgery and postoperative radiation therapy was examined.

RESULTS

Liposarcomas (47%) and leiomyosarcomas (29%) were the histologic types most commonly found. Grade of malignancy was defined as medium to high (II/III) in 44% and as low (I) in 38%. Complete (extended or marginal) resection of the tumor was achieved in 29 patients. After complete resection, the 5-year survival rate and the local recurrence rate were 35% and 63%, respectively. Extended surgery (performed in eight patients) showed a local recurrence rate of 50%. Thirteen patients received high-dose postoperative radiation therapy, which was found to have a significant favorable effect on the recurrence-free interval (P < 0.01).

CONCLUSIONS

We conclude that complete (extended) resection followed by high-dose postoperative radiation therapy improves the prognostic outcome of patients with retroperitoneal soft tissue sarcomas.