Oncological outcomes after major vascular resections for primary retroperitoneal liposarcoma

Background: The surgical management of retroperitoneal sarcomas frequently involves complex multivisceral resections, however retroperitoneal liposarcoma (LPS) rarely invade major abdominal vessels. The aim of the study was to assess association of major vascular resections with outcome of primary LPS. Methods: All consecutive patients who underwent resection at our institutions for primary LPS between 2002 and 2019 were included. A propensity matched analysis was performed, adjusting the groups for the variables of Sarculator, to assess the effect of vascular resection on oncological outcomes. Results: Overall 425 patients were identified. Twenty-four (5%) patients had vascular resection. At final pathology 18 patients had vascular infiltration, 2 vascular encasement and 4 involvement without infiltration. Vascular resection was associated with longer operative time (480′ vs. 330’; p < 0.001) and greater need for transfusions (4 vs. 0 units; p < 0.001), and was burdened by a higher rate of major complications (54% vs. 25%; p = 0.002). After propensity matched analysis, patients undergoing vascular resection had a lower 5-year OS (60% vs. 81%; p = 0.05), and a higher incidence of local and distant recurrence at 5 years (local: 45% vs. 24%, p = 0.05; distant: 20% vs. 0%, p = 0.04). Conclusions: Vascular resection is feasible and safe even in the context of multivisceral resection for primary retroperitoneal liposarcomas, although associated to a higher complication rate. However, the independent association between vascular involvement and a higher risk of local recurrence, distant metastases and death may imply a more aggressive biology, which should be factored in the initial management of this complex disease.