Objective To investigate the prognosis of postoperative adjuvant therapy for hepatocellular carcinoma after conversion therapy of combined targeted therapy and immunotherapy followed by sequential hepatectomy.

Methods The retrospective cohort study was conducted. The clinicopathological data of 103 patients with initially unresectable hepatocellular carcinoma (HCC) who were admitted to 11 medical centers in China, including Mengchao Hepatobiliary Hospital of Fujian Medical University et al, from November 2019 to May 2023 were collected. There were 83 males and 20 females, aged (54±12)years. All 103 patients underwent conversion therapy of tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) successfully followed by sequential hepatectomy, of which 72 patients undergoing postoperative adjuvant therapy were divided into the adjuvant therapy group, and 31 patients undergoing postoperative follow-up monitoring were divided into the follow-up monitoring group. Observation indicators: (1) follow-up and postoperative condi-tions; (2) analysis of factors influencing recurrence-free survival time of patients; (3) stratified ana-lysis. Comparison of count data between group was conducted using the chi-square test or Fisher exact probability. The R software was used to draw survival curves, and the Log‑rank test was used for survival analysis. Univariate and multivariate analyses were conducted using the Cox proportional hazard model.

Results (1) Follow-up and postoperative conditions. All 103 patients were followed up for 21.0(range, 1.9‒47.2)months, with the median recurrence-free survival time of 28.7 months and the 1-, 2-, 3-year recurrence-free survival rates of 68.6%, 55.6%, 41.2%. The median overall survival time of 103 patients was unreached, and the 1-, 2-, 3-year overall survival rates were 90.9%, 82.1%, 69.6%, respectively. The median recurrence-free survival time was 33.1 months in patients of the adjuvant therapy group, with the 1-, 2-year recurrence-free survival rates as 77.2%, 61.5%. The median recurrence-free survival time was 11.1 months in patients of the follow-up monitoring group, with the 1-, 2-year recurrence-free survival rates as 46.6%, 40.8%. There was a significant difference in recurrence-free survival between the two groups of patients (χ²=5.492, P<0.05). (2) Analysis of factors influencing recurrence-free survival time of patients. Results of multivariate analy-sis showed that pathologic complete response and postoperative adjuvant therapy were independent factors influencing recurrence-free survival time of HCC patients undergoing conversion therapy of combined targeted therapy and immunotherapy followed by sequential hepatectomy (hazard ratio=0.297, 0.492, 95% confidence interval as 0.137‒0.647, 0.268‒0.903, P<0.05). (3) Stratified analysis. Of the 71 patients with non-pathologic complete response, the median recurrence-free survival time of 48 patients in the adjuvant therapy group was 24.0 months, with the 1-, 2-year recurrence-free survival rates as 67.4%, 48.8%. The median recurrence-free survival time of 23 patients with non-pathological complete response in the follow-up monitoring group was 7.4 months, with the 1-, 2-year recurrence-free survival rates as 35.0%, 26.3%. There was a significant difference in recurrence-free survival between the 48 patients with non-pathologic complete response in the adjuvant therapy group and the 23 patients with non-pathologic complete response in the follow-up monitoring group (χ²=5.241, P<0.05).

Conclusion For HCC patients with conversion therapy of TKIs and ICIs followed by sequential hepatectomy, postoperative adjuvant therapy, compared to postoperative follow-up monitoring, can prolong the recurrence-free survival time of patients, of whom cases with non-pathologic complete response can benefit from adjuvant therapy.