e15642 Background: Patients with metastatic hepatocellular carcinoma (HCC) are diagnosed more frequently because of introduction of increasingly sensitive imaging modalities. The majority of these patients die of progressive intrahepatic tumor but not due to extrahepatic metastasis. There has been little information about the role of primary tumor resection (PTR) for metastatic HCC patients with resectable primary tumor. Methods: Metastatic HCC patients recommended PTR were identified in SEER registry between 2004 and 2013. The effect of PTR on overall and cancer-specific survival (OS and CSS) using log-rank test and Cox proportional hazard regression model, as well as propensity score matching was assessed. Additionally, validation was performed in another cohort from Sun Yat-sen Memorial hospital (n = 131). Results: Overall, 529 metastatic HCC patients with resectable primary tumor were included. Of those 230 patients underwent PTR but 299 did not. The percentage of PTR among resectable metastatic HCCs increased from 38.6% in 2004 to 70.3% in 2013. PTR was associated with improved OS (hazard ratio (HR) 0.310, 95% CI 0.241-0.400, P< 0.001) and CSS (HR 0.326, 95% CI 0.250-0.425, P< 0.001) in the propensity score- matched patients. This improvement in outcomes remained significant after sensitivity analyses using multiple imputation. Furthermore, consistent with observations in SEER, PTR was correlated with improved OS (HR 0.496, 95% CI 0.294-0.838, P= 0.009) and CSS (HR 0.538, 95% CI 0.307-0.945, P= 0.031) in the validation cohort from Sun Yat-sen Memorial hospital. Conclusions: This study, the first population-based analysis using propensity score matching and multiple imputation, demonstrated that PTR has a favorable impact on prognosis in patients with metastatic HCC. Further prospective randomized trials is needed to conclusively determine whether metastatic HCC patients with resectable primary tumor should be offered aggressive locoregional surgery.
Colorectal adenocarcinoma patients with M1a diseases gain more clinical benefits from palliative primary tumor resection than those with M1b diseases: A propensity score matching analysis
