Retroperitoneal sarcomas: patterns of care in advanced stages, prognostic factors and focus on main histological subtypes: a multicenter analysis of the French Sarcoma Group.

Background: Retroperitoneal sarcomas (RPS) are heterogeneous. Advanced stages include unresectable locoregional (LR) disease, abdominal sarcomatosis and distant metastasis. There is no available report assessing palliative chemotherapy in advanced RPS. This study analyzes management and outcome in a large cohort of patients with advanced RPS, considering main histological subtypes separately.
Patients and Methods: We conducted a retrospective analysis of adult patients diagnosed with a RPS between 1 January 1988 and 31 December 2008 across 12 centers of the French Sarcoma Group. All cases were centrally reviewed by an expert pathologist.
Results: Five-hundred eighty-six patients were included, 299 patients received palliative chemotherapy, with a median of two lines (range 0-8). Fifty patients underwent palliative surgery. Two hundred fifty-five patients (85%) were assessable for response after first line of chemotherapy. Among them, 69 patients (27%) had progressive disease, 145 (57%) had stable disease, 37 (14.5%) had partial response and 4 (1.5%) complete response. Median time from first line of palliative chemotherapy to progression was 5.9 months [4.9-7.3] and median overall survival (OS), 15.8 months [13-18]. In multivariate analysis, prognosis factors independently associated with poor OS were male gender, performance status (PS) >1 and grade >1. There was no difference according to stage of disease. Palliative surgery did not appear to add any survival benefit.
Conclusion: These results emphasize the scarcity of available options for RPS in the advanced setting and the urgent need to develop new strategies. Patients with good PS should be included in clinical trials and best supportive care should be considered in those with poor PS.