Long-term prognosis of primary retroperitoneal soft tissue sarcoma

Aims To evaluate the result of treatment and long-term outcome of a population-based cohort of patients with retroperitoneal soft tissue sarcoma (RSTS). Methods Between 1 January 1989 and 1 January 1994, 143 patients diagnosed as having primary RSTS were selected from a national pathology database (PALGA) in the Netherlands. In this population-based group of patients, the result of surgery, overall survival (OS) and disease-free survival (DFS) were analysed as well as factors affecting OS and DFS. Median follow-up was 10.2 years. Results Operative treatment resulted in a complete tumour resection in 55% of the patients (n = 78), low- and intermediate-grade tumours were more often completely resected than high-grade tumours (P = 0.016). Five- and 10-year cumulative OS was 39% and 21%, respectively, while DFS was 22% and 17%, respectively. In a multivariate analysis low malignancy grade (P = 0.017) and a complete tumour resection (P < 0.001) were associated with better OS. Conclusions Complete tumour resection and low malignancy grade were independent favourable prognosticators. However, these factors were related too, since surgical success was influenced by malignancy grade.