The influence of surgical resection margins on patient survival in retroperitoneal soft tissue sarcoma is determined by tumor differentiation.

PURPOSE: Retroperitoneal sarcoma (RPS) is a rare malignancy with poor long-term prognosis. Diagnosis often occurs at advanced stages, challenging complete resection. This study analyzes prognostic factors influencing patient survival with particular focus on the interaction between tumor differentiation and surgical radicality.

METHODS

A series of 223 patients surgically treated for RPS between 2009 and 2024 was analyzed. Histopathological findings, including tumor grading and resection margins, were correlated with overall survival (OS) and progression-free survival (PFS).

RESULTS

Median follow-up was 32.6 months. Median OS was 67.4 months (95% CI: 45.3-89.5). Regarding histology, median OS was 123.5 months (95% CI: 111.2-135.9) for well-differentiated liposarcoma (WDLPS), 32.6 months (95% CI: 15.6-49.5) for dedifferentiated liposarcoma (DDLPS), 52.6 months (95% CI: 42.4-62.9) for leiomyosarcoma (LMS), and 67.5 months (95% CI: 38.6-96.3) for other RPS subtypes. Tumor grading significantly influenced patient survival: median OS was 121.2 months for G1 (95% CI: 101.3-141.2), 59.7 months for G2 (95% CI: 30.3-89.1), and 24.1 months for G3 tumors (95% CI: 4.3-44.0). As to resection margins, median OS was 89.9 months (95% CI: 16.2-163.7) for R0, 69.6 months (95% CI: 27.3-111.8) for R1 and 13.6 months (95% CI: 0.0-34.5) for R2 resections. Within the G2 subgroup, R2 resulted in significantly inferior outcomes compared to pooled R0/R1 resections (p < 0.003), whereas no significant difference was observable in G1 or G3 RPS.

CONCLUSION

Tumor biology drives the prognosis of RPS, attenuating the relative impact of resection margins in G1 and G3 RPS. Surgical radicality remains a decisive prognostic factor, particularly in G2 RPS. Consequently, tumor grading could serve as an additional compass within histology-driven treatment frameworks to individualize surgical decision-making.