Epidemiology, survival, and treatment of liposarcoma subtypes: An analysis of the national cancer database.

Abstract

e23535 Background: Liposarcomas are a soft tissue sarcoma which grow in adipose tissue, mainly in the subcutaneous fat of the limbs, and are the most common type of soft tissue sarcoma. Relatively little is known about the epidemiology, prevalence, and survival of various histological subtypes of liposarcoma, therefore, in the largest study to date, we analyzed this patient population using the NCDB. Methods: The National Cancer Database (NCDB) was used to identify patients diagnosed with Liposarcoma from 2004 to 2019 using the histology codes 8850, 8851, 8852, 8853, 8855, and 8858 as assigned by the Commission on Cancer Accreditation program. Kaplan-Meier, Chi-Square, and Cox Proportional Hazards tests were performed. Data was analyzed using SPSS version 27 and statistical significance was set at α = 0.05. Results: We identified 19,351 patients with liposarcoma. Mean age at diagnosis was 59 years for all subtypes and 83.3% of patients were white. Well-differentiated tumors were the most common histological subtype (34.8%), conferred the longest overall survival, and were the largest tumors on average. Round-cell tumors were the rarest (2.4%) and had smaller average tumor size than other subtypes. Patients with the de-differentiated subtype (20.5%) experienced the lowest median survival (70.5 months; p < 0.05) and an increased hazard ratio (HR = 2.8; p < 0.05) after controlling for other subtypes, age, and stage at diagnosis. Surgery was the mainstay of therapy with 90% of patients receiving surgery. 11.2% received additional adjuvant chemotherapy and 2.8% received adjuvant radiotherapy. Round cell and Myxoid tumors were most amenable to resection (89.8% and 88.9% of patients having no residual tumor) compared to only 64.4% of dedifferentiated tumors with complete surgical resection. Conclusions: Liposarcomas are a heterogeneous group of tumors which carry unique patterns of presentation, treatment, and prognosis. Well differentiated tumors are common and amenable to treatment; de-differentiated tumors are more aggressive and remain difficult to fully treat.