Prediction of Recurrence-Free and Overall Survival in Retroperitoneal Well-Differentiated and Dedifferentiated Liposarcoma After Surgery.

This study was aimed at creating an effective model for predicting the course of the disease in retroperitoneal well-differentiated (WDLPS) and dedifferentiated (DDLPS) liposarcomas after surgery. The study included 111 patients with WDLPS and 74 patients with DDLPS. We developed a methodology for stratification of patients into prognostic groups. Overall survival (OS) and recurrence-free survival (RFS) were analyzed in accordance with it. The highest OS was achieved in the group "favorable prognosis," while the shortest OS was in the group "extremely poor prognosis" ( p  < 0.001). The median OS in the "favorable prognosis" group was 225 (95% CI , 174, 276) months; "intermediate prognosis" - 130 (95% CI , 115, 145) months; "poor prognosis" - 90 (95% CI , 79, 101) months; and "extremely poor prognosis" - 22 (95% CI , 15, 29) months. The highest RFS was achieved in the group "favorable prognosis," while the shortest RFS was achieved in the group "extremely poor prognosis" ( p  < 0.001). The median RFS in the "favorable prognosis" group was 80 (95% CI , 65, 95) months; "intermediate prognosis" - 47 (95% CI , 33, 61) months; "poor prognosis" - 26 (95% CI , 24, 28) months; "extremely poor prognosis" - 10 (95% CI , 6, 14) months. The method of predicting recurrence-free and overall survival demonstrates an adequate distribution of patients and the reliability of intergroup differences in the survival rate.