Objective To investigate the treatment methods for patients with gastric cancer liver metastasis and prognostic factors.

Methods The retrospective cohort study was conducted. The clinicopathological data of 282 patients with gastric cancer liver metastasis who were admitted to Peking University Cancer Hospital from January 1st,2010 to January 1st,2020 were collected. There were 237 males and 45 females, aged (66±10)years. Of the 282 patients, there were 94 cases with liver oligometastasis and 188 cases with liver multiple metastases. Patients underwent surgical treatment, systemic treatment or local treatment based on the individual condition. Observation indicators: (1) treatment methods for patients with gastric cancer liver metastasis; (2) follow-up and prognosis of patients with gastric cancer liver metastasis; (3) prognostic factors analysis in patients with gastric cancer liver metastasis. Comparison of count data between groups was conducted using the chi‑square test. Comparison of ordinal data was conducted using the nonparameter rank sum test. The univariate analysis was conducted using the log-rank test. The multivariate analysis was conducted using the Cox proportional hazards regression model, and relevant variables were screened through stepwise regression forward method. The Kaplan‑Meier method was used to calculate survival rate and plot survival curve, and the log‑rank test was used for survival analysis.

Results (1) Treat-ment methods for patients with gastric cancer liver metastasis. There were significant differences in surgical treatment methods, hepatic artery infusion chemotherapy, and radiofrequency ablation between the 94 patients with gastric cancer liver oligometastasis and the 188 patients with gastric cancer liver multiple metastases (χ²=21.97, 6.04, 8.78, P<0.05). (2) Follow-up and prognosis of patients with gastric cancer liver metastasis. All 282 patients with gastric cancer liver metastasis were followed up for 781(range, 3-4 100)days, and the 1‑, 3‑, 5‑year overall survival rates were 61.0%, 19.5%, 11.0%, respectively. The overall survival time and 1‑, 3‑, 5‑year overall survival rates were 659(range, 549-769)days and 69.1%, 30.9%, 18.1% in patients with gastric cancer liver oligometastasis, versus 519(range, 451-587)days and 56.9%, 13.8%, 7.4% in patients with gastric cancer liver multiple metastases, showing a significant difference in survival situations between them (χ²=8.45, P<0.05).(3) Prognostic factors analysis in patients with gastric cancer liver metastasis. Results of multi-variate analysis showed that Eastern Cooperative Oncology Group (ECOG) score, surgical treatment methods, chemotherapy, targeted therapy, radiofrequency ablation were all independent factors affecting prognosis of patients with gastric cancer liver metastasis (odds ratio=3.68, 0.82, 0.58, 0.64, 0.52, 95% confidence interval as 1.85-7.33, 0.67-1.00, 0.40-0.86, 0.44-0.92, 0.30-0.90, P<0.05).

Conclusions The treatment methods for patients with gastric cancer liver oligometastasis and multiple liver metastases are different, with the former mostly using surgical treatment and the latter mostly using non‑surgical treatment. Patients with gastric cancer liver oligometastasis have better prognosis than patients with multiple liver metastases. ECOG score, surgical treatment methods, chemo-therapy, targeted therapy, radiofrequency ablation are independent factors affecting prognosis of patients with gastric cancer liver metastasis.