Prognostic factors in primary retroperitoneal soft-tissue sarcomas. We analyzed independent treatment variables (age, sex, signs and symptoms, site, size, histopathologic findings, grade, and clinical presentation) and treatment-dependent variables (resectability, type of operation, surgical margins, surgical boundaries, microscopic margins, adjuvant radiotherapy, and adjuvant chemotherapy) in 80 patients with primary retroperitoneal soft-tissue sarcomas admitted from 1982 through 1988. Both univariate and multivariate analysis of survival and disease-free survival were performed. The major factor in survival outcome was the ability to completely resect the lesion. When the 62 patients who underwent complete resection were examined, the only independent prognostic factor for both survival and disease-free survival was grade. We conclude that completeness of resection and grade of the lesion are primary determinants of survival. Once all tumor is macroscopically removed, no advantage could be demonstrated by more extensive surgical resection or current adjuvant therapy. 