Prognostic study of neoadjuvant therapy for pancreatic cancer based on propensity score matching and subgroup analysis
10.3760/cma.j.cn115396-20241012-00309
- VernacularTitle:基于倾向性得分匹配和亚组分析的胰腺癌新辅助治疗预后研究
- Author:
Xiaohao ZHENG
1
;
Jingyu ZHANG
;
Xiaojie CHEN
;
Zhen HAO
;
Jing LIU
;
Zewen ZHANG
;
Wanqing YU
;
Yun YANG
Author Information
1. 首都医科大学附属北京友谊医院普通外科中心 消化健康全国重点实验室 国家消化系统疾病临床医学研究中心，北京 100050
- Keywords:
Pancreatic neoplasms;
Chemotherapy, adjuvant;
Radiotherapy, adjuvant;
Propensity score matching;
Subgroup analysis
- From:
International Journal of Surgery
2025;52(4):230-238
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate whether neoadjuvant therapy can improve the prognosis of patients with pancreatic cancer.Methods:A retrospective case-control study analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database on 12, 103 patients who underwent surgical treatment between January 1, 2010, and December 31, 2021. Patients were divided into the neoadjuvant therapy group ( n=3 276) and the upfront surgery group ( n=8 827) based on whether they received neoadjuvant treatment. The neoadjuvant therapy group included 2 342 patients receiving neoadjuvant chemotherapy and 934 patients receiving neoadjuvant chemoradiotherapy. The upfront surgery group consisted of 4 335 patients receiving adjuvant chemotherapy, 1 987 patients receiving adjuvant chemoradiotherapy, 63 patients receiving adjuvant radiotherapy, and 2 442 patients undergoing surgery alone. Propensity score matching was used to eliminate group differences and create a cohort with no statistical differences in other clinicopathological features except for the grouping variable. Variables such as age, gender, tumor location, race, population of residence, tumor diameter, household income, TNM stage, and information on radiotherapy and chemotherapy were used for 1∶1 case matching. T stage, N stage, and the use of radiotherapy or chemotherapy were matched exactly. After matching, 1 182 patients were included in each group: the neoadjuvant therapy group contained 1 155 patients receiving neoadjuvant chemoradiotherapy and 27 receiving neoadjuvant chemotherapy, while the upfront surgery group comprised 848 patients receiving adjuvant chemotherapy and 334 receiving adjuvant chemoradiotherapy. TNM staging was reported according to the 7th edition of the AJCC guidelines. The primary outcome was overall survival. Measurement data with skewed distributions were expressed as M( Q1, Q3), and intergroup comparisons were conducted using the Wilcoxon rank-sum test. Categorical data were compared using the chi-square test or the Fisher′s exact test. The Log-rank test and subgroup analyses to assess interactions between neoadjuvant therapy and subgroup in COX regression models were used to compare survival benefits across variables. Landmark analysis was performed to create segmented survival curves, studying the impact of neoadjuvant therapy on prognosis during different follow-up periods. Results:The neoadjuvant therapy group had a higher proportion of T 4 tumor involving celiac axis, superior mesenteric artery, and/or common hepatic artery compared to the upfront surgery group (14.7% vs 2.8%, P<0.001). Additionally, significant differences were observed between groups in terms of race, location, population of residence, age, tumor diameter, tumor stage, and adjuvant therapy regimen ( P<0.05). The median overall survival time in the neoadjuvant therapy group was 30 months, compared to 22 months in the upfront surgery group ( P<0.001). In the neoadjuvant therapy group, the median survival was 30 months for both neoadjuvant chemotherapy and chemoradiotherapy patients; in the upfront surgery group, it was 26 months for both adjuvant chemotherapy and chemoradiotherapy patients, 17 months for adjuvant radiotherapy patients, and 12 months for surgery-only patients. After propensity score matching, there were no differences in the distribution of clinical characteristics between groups ( P>0.05), and all patients in the matched cohort had received chemotherapy. The matched neoadjuvant therapy group had a longer median overall survival compared to the upfront surgery group (30 months vs 27 months, P<0.001). Subgroup interaction analysis revealed that T stage had a significant interaction with neoadjuvant therapy, both before (T 4 stage: HR=0.382, 95% CI: 0.319-0.458; T 2-T 3 stages: HR=0.696, 95% CI: 0.656-0.738; T 1 stage: HR=1.199, 95% CI: 0.867-1.657; interaction P<0.001) and after matching (T 4 stage: HR=0.581, 95% CI: 0.414-0.814; T 2-T 3 stages: HR=0.827, 95% CI: 0.734-0.931; T 1 stage: HR=1.320, 95% CI: 0.716-2.433; interaction P=0.043). Subgroup interaction analysis indicated that T 1 patients did not benefit from neoadjuvant therapy; survival curves plotted for matched T 1 patients showed no difference in survival between the neoadjuvant therapy group and the upfront surgery group ( P=0.323). Conversely, non-T 1 (T 2-T 4) stage patients showed significant survival benefits in both unmatched and matched cohorts ( P<0.001). Landmark analysis showing that the survival benefits occurred mainly in the early postoperative period of up to 3 years ( P<0.001), but there was no difference in overall survival between the neoadjuvant therapy group and the upfront surgery group of >3 years ( P>0.05). Patients with Arterial invasion (T 4 stage compared to T 1-T 3 stages) showed a similarly significant interaction with the benefit of neoadjuvant therapy in both the pre-matching cohort (interaction P<0.001) and the post-matching cohort (interaction P=0.037). Patients with T 4 stage disease in the neoadjuvant therapy group had longer overall survival compared to the upfront surgery group (median overall survival in pre-matching cohort: 30 months vs 13 months, P<0.001; median overall survival in post-matching cohort: 28 months vs 18 months, P=0.001). Among T 4 stage patients in the post-matching cohort, neoadjuvant therapy provided significant survival benefits during the early postoperative period of up to 3 years ( P=0.001). However, there was no difference in overall survival between the neoadjuvant therapy group and the direct surgery group beyond 3 years( P=0.729). Conclusions:The prognosis in the neoadjuvant therapy group was better than in the upfront surgery group. Propensity score matching and subgroup interaction analysis showed that non-T 1 and T 4 stage patients benefited more from neoadjuvant therapy, with benefits mainly seen in the early postoperative period (≤3 years).
