Trend of sphincter-preserving surgeries for resectable low rectal cancer: A 20-year experience in China.

Abstract

3615 Background: Over the last decades, patients with low rectal cancer have realized better functional, morbidity, and quality-of-life outcomes from improvements in surgical techniques in sphincter preservation. We aimed to quantify the trend in sphincter-preserving surgeries for low rectal cancer over 20 years in China. Methods: Between November 1999 and October 2021, a cohort of patients with pathologically confirmed primary malignant rectal tumor ≤5cm from the anal verge and who received selective surgery at Changhai Hospital, was identified. Demographic and clinical data were extracted from electronic medical records. Survival data were collected from outpatient medical records and follow-up phone interviews. A Joinpoint Regression Model was used to analyze trends in surgical procedures by average annual percentage change (AAPC). A Cox proportional hazards regression model adjusting for demographic and clinicopathological confounders was used to assess the overall survival for patients with sphincter-preserving surgery vs. abdominoperineal resection (APR). Results: Among 19,276 patients with colorectal cancer, 4,072 (21.1%) had a tumor in the low rectum during the study period; 3,025 (74.2%) underwent a sphincter-preserving surgery and 1,047 (25.7%) received APR. Sphincter-preserving surgery increased 3.6% per year (AAPC 3.6, p=.006). Anterior resection was the most performed procedure (86.3%) and maintained a steady trend (AAPC 0.13, p=.49), while intersphincteric resection (including conformal sphincter preservation operation) increased 49.4% annually (AAPC 49.4, p=.003). Laparoscopic techniques increased 15.1% per year (AAPC 15.1, p=.035). Sphincter-preserving surgery increased annually for tumors ≤2cm, 2-3cm and 3-4cm from the anal verge (AAPC 7.08, p=.001; 4.69, p=.001; 2.66, p=.001, respectively). A total of 2,854 patients had sufficient vital status data for inclusion in the survival analysis. The characteristics of those with and without a follow-up encounter were comparable. Patients with sphincter-preserving surgery had a lower risk of death compared to APR (adjusted HR 0.78, 95% CI, 0.65-0.93, p=.01). Conclusions: Utilization of sphincter-preserving surgeries increased significantly over the last 20 years. Patients with low rectal cancer who underwent sphincter preservation had better survival than similar patients who underwent APR.[Table: see text]