Economic outcomes of robot-assisted surgery for gastric and colorectal cancer at a general hospital: a real-world analysis of the volume-cost dilemma.

PURPOSE: Most economic analyses of robot-assisted surgery (RAS) have been conducted at high-volume centers. We evaluated RAS economics at a general hospital, hypothesizing a Volume-Cost Dilemma of disproportionately high per-case fixed costs at low case volumes. METHODS: This retrospective study compared robotic-assisted and laparoscopic surgery for 125 curative gastric cancer resections (Laparoscopic n=63, Robotic n=62) and 161 colorectal cancer resections (Laparoscopic n=65, Robotic n=96) performed between 2021 and 2024. Gross Surgical Profit (GSP) was defined as the surgical fee minus materials, labor (micro-costing), and maintenance costs. Break-even volume was estimated from the median marginal profit per robotic case (gastric cancer reference model). RESULTS: The median GSP was significantly lower in the Robotic group for gastric (+¥468,181 vs. -¥148,835) and colorectal cancer (+¥394,959 vs. -¥190,573; both p<0.001), driven by 17.5-fold higher robotic maintenance costs (¥386,000 vs. ¥22,000/case). Low anterior resection alone showed a positive Robotic GSP (+¥69,876). Break-even required 233 robotic cases under the gastric cancer reference model, which is 1.6 times the current volume of 143. CONCLUSIONS: A structural Volume-Cost Dilemma, driven by high fixed-maintenance costs, was observed in RAS at a general hospital, proposed as an interpretive framework. Resolving this requires in-hospital cost reduction combined with centralization under the 2026 reimbursement reform, underscoring the need for volume-sensitive policy and multicenter research.