Clinical value of self‑expandable metal stents implantation combined with neoadjuvant therapy in the treatment of obstructive colorectal cancer

Objective To investigate the clinical value of self‑expandable metal stents (SEMS) implantation combined with neoadjuvant therapy (NAT) in the treatment of obstructive colorectal cancer.

Methods The retrospective cohort study was conducted. The clinicopathological data of 130 patients with obstructive colorectal cancer who were admitted to two medical centers, including 59 cases from Tangdu Hospital of Air Force Medical University and 71 cases from Affiliated Beijing Chaoyang Hospital of Capital Medical University, from January 2011 to December 2025 were collected. There were 82 males and 48 females, aged 62(26,75) years. All 130 patients were divided into two groups based on treatment methods. The group of 84 patients who underwent SEMS implantation combined with NAT bridging radical surgery was designated as the combined group, while the group of 46 patients who underwent SEMS implantation bridging radical surgery was designated as the stent group. The 130 patients were further divided into two cohorts for analysis, including cohort 1 of 62 patients who were admitted from January 2011 to December 2020, and cohort 2 of 68 patients who were admitted from January 2021 to December 2025, respectively. Observation indicators: (1) comparison of general data between patients in the combined group and stent group in different cohorts; (2) NAT status of patients in the combined group of different cohorts; (3) complications related to stent implantation in patients in different cohorts; (4) perioperative conditions of patients in different cohorts; (5) survival status of patients in different cohorts. Comparison of measurement data with normal distribution between groups was conducted using the independent sample t test. Comparison of measurement data with skewed distribution between groups was conducted using the Mann‑Whitney U test. Comparison of count data between groups was conducted using the chi‑square test, corrected chi‑square test or Fisher exact probability. Comparison of ordinal data between groups was conducted using the Mann-Whitney U test. The Kaplan‑Meier method was used to calculate survival time and draw survival curves, and Log‑rank test was used for survival analysis.

Results (1) Comparison of general data between patients in the combined group and stent group in different cohorts: in cohort 1, the number of patients in the combined group and stent group was 33 and 29, respectively, and the preoperative hemoglobin levels was (104±19) g/L and (118±17) g/L, respectively, showing a significant difference between the two groups (t=3.07, P<0.05). In cohort 2, the number of patients in the combined group and stent group was 51 and 17, respectively, and there was no significant difference in general data between the two groups (P>0.05). (2) NAT status of patients in the combined group of different cohorts: in cohort 1, all 33 patients in the combined group received NAT as chemotherapy, with a course of 2(1,4) cycles. In cohort 2, 51 patients in the combined group received NAT, including 38 cases of chemotherapy, 6 cases of chemotherapy combined with targeted therapy and 7 cases of chemotherapy combined with immunotherapy, with the NAT course of 3(1,6) cycles. (3) Complications related to stent implantation in patients in different cohorts: in cohort 1, among the 33 patients in the combined group, there was 1 case of perforation, 2 cases of re-intestinal obstruction, and 0 case of stent detachment. Among the 29 patients in the stent group, the above indicators were 0, 1, and 0 case, respectively. There was no significant difference in complications related to stent implantation in patients between the two groups (P>0.05). In cohort 2, among the 51 patients in the combined group, there was 1 case of perforation, 3 cases of re‑intestinal obstruction, and 1 case of stent detachment. Among the 17 patients in the stent group, the above indicators were 1, 0, and 0 case, respectively. There was no significant difference in complications related to stent implantation in patients between the two groups (P>0.05). (4) Perioperative conditions of patients in different cohorts: in cohort 1, among the patients who underwent NAT in the combined group, there was 1 case evaluated as tumor T downstaging, 6 cases evaluated as tumor N downstaging, 5 cases evaluated as 0-1 grading of tumor regression grade (TRG), and 11 cases evaluated as 2-3 grading of TRG. There were significant differences in interval time from stent implantation to radical surgery and postoperative complications in patients between the combined group and stent group (Z=-5.72, χ²=6.01, P<0.05). In cohort 2, among the patients who underwent NAT in the combined group, there was 14 cases evaluated as tumor T downstaging, 23 cases evaluated as tumor N down-staging, 10 cases evaluated as 0-1 grading of TRG, and 37 cases evaluated as 2-3 grading of TRG. There were significant differences in interval time from stent implantation to radical surgery, operation time and tumor pathological N staging in patients between the combined group and stent group (Z=-6.11, -2.22, -2.02, P<0.05). (5) Survival status of patients in different cohorts: in cohort 1, 32 patients in the combined group completed follow‑up, with a follow‑up time of 62(4,133) months, and the 1‑year, 3‑year, and 5‑year disease‑free survival rates and 1‑year, 3‑year, and 5‑year overall survival rates were 97.0%, 80.3%, 73.0%, and 93.9%, 84.8%, 66.0%, respectively. Twenty‑five patients in the stent group completed follow‑up, with a follow‑up time of 81(11,158) months, and the 1‑year, 3‑year, and 5‑year disease‑free survival rates and 1‑year, 3‑year, and 5‑year overall survival rates were 96.6%, 75.1%, 57.2%, and 96.6%, 79.3%, 62.1%, respectively. There was no significant difference in disease‑free survival and overall survival in patients between the two groups (χ²=1.42, 0.19, P>0.05). In cohort 2, all 51 patients in the combined group completed follow‑up, with a follow‑up time of 41(1,66) months, and the 1‑year, 3‑year disease‑free survival rates and 1‑year, 3‑year overall survival rates were 93.7%, 76.9% and 100.0%, 94.3%, respectively. All 17 patients in the stent group completed follow‑up, with a follow‑up time of 31(6,50) months, and the 1‑year, 3‑year disease‑free survival rates and 1‑year, 3‑year overall survival rates were 94.1%, 52.4% and 93.8%, 60.8%, respec-tively. There was a significant difference in overall survival in patients between the two groups (χ²=8.48, P<0.05), and there was no significant difference in disease-free free survival (χ²=1.62, P>0.05).

Conclusion Compared to SEMS implantation bridging radical surgery, the combination of SEMS implantation and NAT bridging radical surgery does not increase the risk of complications related to stent implantation in obstructive colorectal cancer with low ratio of postoperative complication, and is expected to improve patient overall survival benefits.