Objective To investigate the influencing factors for early tumor recurrence and the efficacy of adjuvant chemotherapy in gallbladder carcinoma (GBC) patients after curative-intent resection.

Methods The retrospective case-control study was conducted. The clinicopathological data of 506 patients with GBC in 11 medical centers, including The First Affiliated Hospital of Xi'an Jiaotong University et al, from January 2016 to December 2020 were collected. There were 168 males and 338 females, aged (62±11)years. All patients underwent curative-intent resection of GBC, and they were divided into patients with and without early recurrence based on time to postoperative recurrence. Observation indicators: (1) treatment; (2) follow-up and survival of patients; (3) analysis of influencing factors for early tumor recurrence after curative-intent resection of GBC; (4) efficacy of postoperative adjuvant chemotherapy. Measurement data with normal distribution were represented as Mean±SD, and measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test. Comparison of ordinal data was conducted using the Mann-Whitney U test. Univariate analysis was conducted using the corresponding statistical methods based on data type. Multivariate analysis was conducted using the Logistic regression model with forward method. The Kaplan-Meier method was used to draw survival curve and calculate survival rate, and Log-Rank test was used for survival analysis.

Results (1) Treatment. Of 506 patients, there were 112 cases with postoperative adjuvant chemotherapy, and 394 cases without postopera-tive adjuvant chemotherapy. They underwent 5(range, 3-9)cycles of postoperative adjuvant chemo-therapy. (2) Follow-up and survival of patients. All 506 patients underwent postoperative follow-up, with the follow-up time of 55(range, 34-93)months. During the follow-up, there were 248 patients with tumor recurrence, including 158 cases of early recurrence and 90 cases of late recurrence, and there were 258 patients without tumor recurrence. Of 506 patients, 275 cases survived, and 231 cases died of multiple organ failure caused by tumor recurrence and metastasis. The postoperative recurr-ence-free survival time, overall survival time were 52(range,1-93)months, 62(range, 2-93)months. The 1-, 3-, 5-year disease-free survival rates and 1-, 3-, 5-year overall survival rates of the 506 pati-ents were 68.8%, 53.8%, 47.9% and 78.3%, 58.7%, 51.6%, respectively. Results of survival analysis showed that the median overall survival time of 158 patients with postoperative early recurrence and 348 patients without postoperative early recurrence (including 90 cases of late recurrence and 258 cases of no tumor recurrence) were 9(range, 2-73)months and unreached, showing a significant difference between them (χ²=456.15, P<0.05). (3) Analysis of influencing factors for early tumor recurrence after curative-intent resection of GBC. Results of multivariate analysis showed that carcinoembryonic antigen (CEA) >5.0 μg/L, poorly differentiated tumor, liver invasion, and tumor N staging as stage N1-N2 were independent risk factors influencing early tumor recurrence after cura-tive-intent resection of GBC (odds ratio=2.74, 6.20, 1.81, 2.93, 4.82, 95% confidence interval as 1.62-4.64, 1.82-21.12, 1.15-3.08, 1.68-5.09, 1.91-12.18, P<0.05), while postoperative adjuvant chemo-therapy was an independent protect factor (odds ratio=0.39, 95% confidence interval as 0.21-0.71, P<0.05). (4) Efficacy of postoperative adjuvant chemotherapy. The median overall survival time of 394 patients without postoperative adjuvant chemotherapy and 112 patients with postoperative adjuvant chemotherapy were 57(range, 2-93)months and unreached, showing a significant differ-ence between them (χ²=9.38, P<0.05). Of the 158 patients with postoperative early recurrence after curative-intent resection of GBC, 135 cases didn't receive adjuvant chemotherapy and 23 cases received adjuvant chemotherapy, with the overall survival time of 8(range, 2-73)months and 17(range, 8-61)months, respectively, showing a significant difference between them (χ²=7.68, P<0.05).

Conclusions CEA >5.0 μg/L, poorly differentiated tumor, liver invasion, and tumor N staging as stage N1-N2 are independent risk factors influencing early tumor recurrence after curative-intent resection of GBC, while postoperative adjuvant chemotherapy is an independent protect factor. Postoperative adjuvant chemotherapy can prolong the overall survival time of patients with post-operative tumor early recurrence.