Is left-sided involvement of hepatocellular carcinoma an important preoperative predictive factor of poor outcome?

BACKGROUND: The tumor location is the most simple clinical factor and important in liver surgery to make surgical procedure. However, no previous study has investigated the prognostic differences and clinical features of hepatocellular carcinoma showing specific laterality. This study is the first report to focus on the laterality and aimed to lead to more simple and useful predictive factor rather than recent complicated predictive models. METHODS: Patients who underwent liver resection for the first time for single tumors located within each lobe between 2000 and 2018 were enrolled. We divided them into two groups based on tumor location: a right-sided group and a left-sided group. Univariable and multivariable analyses were performed to assess survival differences in relation to several other factors. RESULTS: There were 595 eligible patients; the 5-year survival rates and disease-free survival rates were 49.5% and 19.1% in the left-sided group and 55.6% and 24.5% in the right-sided group, respectively (p = 0.026). Statistical analyses revealed that the following preoperative prognostic factors were independently significant (p < 0.05) in the left-sided group: indocyanine green retention rate at 15 min, alpha fetoprotein, protein induced by vitamin K absence or antagonists-II level, and larger tumor size. CONCLUSION: The left-sided group had a poorer prognosis than the right-sided group. A left-sided tumor location is a significant preoperative factor predictive of poor outcome in patients with hepatocellular carcinoma.