Background: Experiences at specialized hepatobiliary centers have demonstrated efficacy of minimally invasive liver resection, but concerns exist regarding whether these procedures would remain effective once disseminated to a broad range of clinical practices. We sought to present the first comparison of MILR and open liver resection (OLR) for primary liver malignancy from a nationally representative cancer registry.
Methods: Cases of liver and intrahepatic bile duct cancer were identified from the National Cancer Data Base Participant Use File. Mixed effects logistic regression and stratified Cox proportional hazards regression were used for analysis. A propensity score matched cohort was used as an alternative form of analysis to evaluate the robustness of results.
Results: A total of 3236 cases were analyzed from 2010 to 2011 with 2581 OLR (80%) and 655 MILR (20%). Of the variation in patient selection for MILR 28.5% was related to treatment at a specific treatment center; however, the proportion of MILR was similar among low-, medium-, and high-volume centers. Overall 90-day mortality was lower at high-volume centers (odds ratio [OR] 0.58; 95% confidence interval [CI] 0.40-0.85) compared with low-volume centers. MILR was similar to OLR in both 90-day mortality and overall survival (OR 0.9; 95% CI 0.62-1.10) and hazard ratio [HR] 0.88 (95% CI 0.72-1.07), regardless of treatment center volume.
Conclusions: MILR for primary liver malignancy is used across a variety of practice settings, with similar outcomes to OLR. While volume is associated with short-term outcomes of liver resection as a whole, this relationship is not explained by adoption of MILR at low-volume centers.