Prognostic Model to Predict Survival Outcome for Curatively Resected Liposarcoma: A Multi-Institutional Experience

Purpose: We performed this study to analyze the clinical features and prognosis of Korean patients with liposarcoma. Patients & Methods: Between October 1986 and April 2013, 231 patients who were diagnosed with liposarcoma by histologic examination were enrolled in this study. Results: The distribution of histologic subtypes was well-differentiated (n = 97, 42%), myxoid (n = 74, 32%), dedifferentiated (n = 32, 13.9%), pleomorphic (n = 15, 6.5%), and round-cell liposarcoma (n = 13, 5.6%). The majority of liposarcomas were located in the lower extremities (35.5%) and retroperitoneum (34.2%). Prognosis was worse for the trunk group compared with the extremity group (median disease-free survival [DFS] 3.3 vs. 9.9 years, respectively, P <0.001). Median DFS was significantly worse in patients with high grade histology compared to those with low grade histology (16.9% vs. 65.7%, P <0.001). The independent prognostic factors associated with survival were histology (hazard ratio [HR] 3.01; 95% confidence interval [CI], 1.82-4.97; P <0.001) and primary site (HR 1.80; 95% CI, 1.12-2.89; P = 0.015). Three risk groups with different survival outcomes were identified: group 1 (n = 98), no risk factors; group 2 (n = 92), one risk factor; and group 3 (n = 41), two risk factors. Conclusions: Histologic subtype and primary site were independent prognostic factors for curatively resected liposarcoma. A prognostic model for patients with liposarcoma clarified distinct groups of patients with good prognostic discrimination.