Risk factors of early recurrence in retroperitoneal liposarcoma.

Introduction: The aim of this study is to identify factors associated to recurrence and survival in primary retroperitoneal liposarcomas.

Methods: Prospective database of 35 patients with primary retroperitoneal liposarcoma treated 2004-2015 were retrospectively analyzed. Exclusion criteria were recurrent and metastatic tumors. Overall survival (OS) and disease-free survival were reviewed. Patient data were compared between patients with or without recurrence within 12 months after surgery. Risk factors were determined using logistic regression analysis.

Results: Five-year OS was 61.1%. One and three-year disease-free survival were 68.6% and 17.1% respectively. OS in the early recurrence group was 36.4 months compared with 43.2 months in the group without early recurrence (P=.011). Early recurrence was associated with a reduction in OS (HR=4.05; CI95%: 1.27-12.96; P=.018). Multifocality and microscopic positive margins R1 were associated with early recurrence. Histologic subtype, margin of resection, histologic grade and multifocality were factors associated with recurrence. Contiguously involved organ resection had a beneficial effect on early recurrence and was associated with an increase in disease-free survival and OS. Adjuvant treatments had no protective effect on recurrence.

Conclusions: This study underlines the crucial role aggressive surgical approach in retroperitoneal Liposarcoma treatment, especially in those patients with histological characteristics that adversely the prognosis.