A systematic review and meta-analysis on prognosis and survival of hepatocellular carcinoma with lung metastasis after hepatectomy

Background: The most common metastatic site of hepatocellular carcinoma (HCC) is lung metastasis. When the patient has lung metastasis, the development of the disease will become very rapid. In severe cases, it will cause rapid death of the patient. Therefore, the treatment of HCC after lung metastasis has become a hot research topic. This study was designed to investigate the curative effect and prognostic factors of hepatectomy in patients with HCC with lung metastasis (LM) (HCC + LM patients) using meta-analysis. Methods: RevMan 5.3 software was used to screen literature based on randomized controlled studies on the curative effect and prognostic factors of hepatectomy for HCC + LM published between January 2000 to January 2020 in the PubMed, Web of Science, Spring, and Science Direct databases. Results: A total of 13 articles were included, comprising 754 patients in the H group and 1,201 patients in the NH group. Meta-analysis results showed that the maximum diameter of liver tumors in the H group was much larger than that in the NH group (MD = -0.62; 95% CI: -1.20 to -0.04; Z=2.09; P=0.04). The survival rate 1, 3, and 5 years after treatment in group H was higher than that in the NH group [Mantel-Haenszel (MH) = 2.91, 2.80, and 4.96; 95% CI: 2.25-3.76, 2.22-3.52, and 3.74-6.59; Z=8.20, 8.73, and 11.09, respectively; P<0.00001], and the mean survival time in group H was much longer than that in the NH group (MD=17.30; 95% CI: 11.78-22.83; Z=6.14; and P<0.00001). Discussion: The MDLT is a prognostic indicator for hepatectomy, and hepatectomy can effectively prolong the survival time of HCC + LM patients.