Comparing Multivisceral Resection with Tumor-only Resection of Liposarcoma Using the Win Ratio

Area of Science:

• Surgical Oncology
• Oncologic Outcomes Research
• Statistical Methodology in Clinical Research

Background:

• Multivisceral resection (MVR) for retroperitoneal liposarcoma (LPS) carries high morbidity without clear survival benefits over tumor-only (TO) resection.
• Novel statistical methods like the win ratio (WR) are needed to compare complex surgical approaches.

Purpose of the Study:

• To compare the outcomes of MVR versus TO resection for LPS using the win ratio (WR) statistical method.
• To evaluate the impact of patient age and tumor involvement on the comparative effectiveness of MVR and TO resection.

Main Methods:

• Retrospective analysis of 958 LPS patients undergoing resection (2004-2015) from the National Cancer Database.
• MVR defined as resection of primary LPS plus adjacent organs; TO resection focused on the primary tumor.
• Win ratio calculated based on a hierarchy: 30/90-day mortality, long-term survival, and severe complications.

Main Results:

• No significant difference in WR between MVR and TO resection in the overall matched cohort (WR 0.82).
• In patients aged 72-90 years, MVR showed a 36% lower odds of winning compared to TO resection (WR 0.64).
• In patients without adjacent tumor involvement, MVR had 33% lower odds of winning versus TO resection (WR 0.67).

Conclusions:

• Win ratio analysis suggests MVR may not improve outcomes in LPS patients without adjacent tumor involvement.
• Findings support less invasive TO resection for select LPS patients, particularly older individuals.
• The WR method provides a robust framework for evaluating complex oncologic surgical strategies.