The impact of liver resection on survival outcomes of hepatocellular carcinoma patients with extrahepatic metastases: A propensity score matching study.
BACKGROUND
The majority of hepatocellular carcinoma patients (HCCs) with extrahepatic metastases die of progressive intrahepatic tumor. There have been little data on the role of primary tumor resection (PTR) for HCCs with extrahepatic metastases but with resectable primary tumors.


METHODS
A retrospective study was conducted on HCCs with extrahepatic metastases with resectable primary tumors who either underwent or did not undergo PTR in the SEER registry between 2004 and 2013. The overall and cancer-specific survivals (OS and CSS) were assessed by the log-rank test and the Cox proportional hazard regression model. A propensity score matching was conducted to minimize biases. Validation was performed in another cohort from the Sun Yat-sen Memorial Hospital (SYSMH).


RESULTS
Of the 529 HCCs with extrahepatic metastases with resectable primary tumors included into this study, 230 patients underwent PTR and 299 did not. The percentages of patients who underwent PTR increased from 38.6% in 2004 to 70.3% in 2013. In the propensity score-matched patients, PTR was associated with improved OS (HR 0.310, P < 0.001) and CSS (HR 0.326, P <0.001). These improvements in survivals remained significant after sensitivity analyses using multiple imputation. In the validation cohort from the SYSMH (n = 131), PTR was also correlated with improved OS (HR 0.508, P = 0.002) and CSS (HR 0.568, P = 0.017).


CONCLUSIONS
This study using propensity score matching and multiple imputation demonstrated that PTR had a favorable impact on the prognosis of HCCs with extrahepatic metastases with resectable primary tumors. Further prospective randomized trials are needed to confirm these findings.
['Mao|Kai|K|', 'Yan|Yongcong|Y|', 'Zhang|Jianlong|J|', 'Wang|Jie|J|', 'Wang|Ruomei|R|', 'Ling|Xiaojuan|X|', 'Liu|Yingyue|Y|', 'Lau|Wan Yee|WY|', 'Jiang|Shuai|S|', 'Liu|Jieqiong|J|0000-0001-7859-3764', 'Xiao|Zhiyu|Z|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D006528:Carcinoma, Hepatocellular D005260:Female D006498:Hepatectomy D006801:Humans D053208:Kaplan-Meier Estimate D008113:Liver Neoplasms D008297:Male D008875:Middle Aged D009362:Neoplasm Metastasis D009367:Neoplasm Staging D009656:North America D057216:Propensity Score D016016:Proportional Hazards Models D062486:Public Health Surveillance D012042:Registries D012189:Retrospective Studies D018426:SEER Program D055815:Young Adult
hepatocellular carcinoma propensity score matching primary tumor resection extrahepatic metastasis surveillance epidemiology and end results database