EP246 - Preoperative T Stage and Trajectory of Low Anterior Resection Syndrome After Sphincter-preserving Surgery for Rectal Cancer: A Retrospective Cohort Study

Sunday, May 10, 2026

8:38 AM - 8:43 AM ET

ePoster Presenter(s)

Jiaqi Li, MD

Student
West China School of Medicine, West China Hospital, Sichuan University, 610041 Chengdu, China
West China School of Medicine, West China Hospital, Sichuan University, Chengdu, China
Chengdu, Sichuan, China (People's Republic)

Disclosure information not submitted.

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Author(s)

XZ

Xianglin Zhang, n/a

student
四川大学
chengdu, Sichuan, China (People's Republic)

Disclosure information not submitted.
YL

Yuxin Lin, Undergraduate Degree (Expected 2026)

Undergraduate Student
West China School of Medicine, Sichuan University
Chengdu, Sichuan, China (People's Republic)

Disclosure information not submitted.
MH

Mingjun Huang, associate professor

head nurse
West China Hospital, Sichuan University
Chengdu City, Sichuan, China (People's Republic)

Disclosure information not submitted.
ll

li li, n/a

surgeon
West China Hospital, Sichuan University
Chengdu, Sichuan, China (People's Republic)

Disclosure information not submitted.

Senior Author(s)

XW

Xiaodong Wang, Chinese Medical Doctor Association

Deputy Chief Physician
West China Hospital
Chengdu, Sichuan, China (People's Republic)

Disclosure information not submitted.

Purpose/Background: To investigate whether preoperative clinical T stage (cT), a conventional prognostic indicator, is associated with the severity and longitudinal trajectory of Low Anterior Resection Syndrome (LARS) in patients with mid-to-low rectal cancer undergoing sphincter-preserving surgery, and to analyze risk factors for LARS development.

Methods/Interventions: We retrospectively analyzed 272 patients treated at West China Hospital between June 2018 and January 2024 using a prospectively maintained follow-up database. LARS scores were assessed using a validated questionnaire at 1, 3, 6, 9, and 12 months postoperatively. Risk factors for major LARS were evaluated by Chi-square tests, Mann-Whitney U tests and binary Logistic regression. Linear mixed models (LMM) were applied to examine temporal LARS score changes.

Results/Outcomes: Contrary to conventional expectations, preoperative cT stage was not significantly associated with major LARS at both early (1-month: p=0.122; 3-month: p=0.408) and later timepoints (6-month: p=0.797; 9-month: p=0.319; 12-month: p=0.061), nor with long-term LARS score trajectories (all p>0.05). LARS scores decreased over time across all cT groups with no significant between-group differences. Higher BMI (p=0.02), shorter tumor distance from anal verge (p < 0.001), moderate differentiation (p < 0.001), diabetes (p=0.02), and neoadjuvant chemotherapy (p=0.006) were independent risk factors for higher LARS scores.

Conclusion/Discussion: Preoperative cT stage is not an independent predictor of LARS severity and its longitudinal changes. This unexpected finding may help manage patients’ expectations towards the prognostic outcomes after sphincter-preserving surgery, supporting psychological adaptation and treatment acceptance. Modifiable factors such as BMI, tumor characteristics, and comorbidities play key roles and should guide individualized counseling and rehabilitation strategies. This study highlights the value of follow-up LARS measurements and LMM-based analyses, providing novel insights into the dynamic trajectory of LARS after sphincter-preserving surgery.