Rectal Cancer
LARS — Bowel Function After Rectal Surgery
Frequency, urgency, and leakage — non-surgical and selected surgical options
Low anterior resection (LAR) preserves the sphincter when oncologically safe, but bowel habit often changes. Low anterior resection syndrome (LARS) describes clustering of frequency, urgency, incomplete emptying, and sometimes leakage. It is common enough to discuss before surgery and manageable afterward.
LARS is not uniform in severity. Diet, medicines, pelvic-floor rehabilitation, and in selected patients transanal irrigation may help. Seek early review when symptoms limit work, sleep, or daily life.
What symptoms define LARS?
Patients may notice frequent and urgent bowel movements, fragmented emptying, difficulty distinguishing gas from stool, nocturnal trips, and occasional incontinence. Symptoms may emerge over weeks to months after surgery; some improve with time.
- Frequency and urgency
- Clustering / incomplete emptying
- Gas–stool discrimination difficulty
- Leakage / control loss
Why does it happen?
A low anastomosis, reduced rectal reservoir, prior radiation, temporary ileostomy, and pelvic nerve effects can contribute. The functional trade-off between LAR and a permanent stoma should be discussed before surgery.
First-line management
Diet modification, antidiarrheal or antispasmodic medicines when appropriate, regular meal timing, and pelvic-floor physiotherapy help many patients. Allow a period of adaptation after stoma reversal.
- Diet and fluid planning
- Medicines when prescribed
- Pelvic-floor rehabilitation
- Stoma / GI nursing support
When to seek specialist review
Do not delay assessment when symptoms severely limit daily life, when leakage causes anemia or weight loss, or when problems persist without improvement. Selected patients may discuss transanal irrigation or reconsideration of a diverting stoma.
Common questions
- Is LARS permanent?Tap for details
Not for everyone. Some improve within the first year; others need longer-term strategies. Early support often helps.
- Should I choose APR instead of LAR?Tap for details
Some patients prefer a permanent stoma based on functional expectations — an individualized, informed choice with oncologic safety first.
- Does pelvic-floor therapy help?Tap for details
Many patients gain better control and less urgency with structured physiotherapy.
Evidence
Scientific sources
Show sources · 3Clinical guidance and patient-education sources for low anterior resection syndrome (LARS) after rectal surgery.
Evidence
Scientific sources
- 1. Rectal cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-upESMO · 2017 (güncellemeler için ESMO GI portalına bakın) · DOI: 10.1093/annonc/mdx224Open source →
- 2. NCCN Clinical Practice Guidelines in Oncology: Rectal CancerNCCN · Güncel sürüm / Current versionOpen source →
- 3. ASCRS clinical practice guidelines libraryAmerican Society of Colon & Rectal Surgeons (ASCRS) · Kılavuz kütüphanesi / Guideline libraryOpen source →
Last reviewed: 21 August 2026. Links go to publisher pages.
Bu içerik bilgilendirme amaçlıdır; tıbbi tavsiye yerine geçmez. TNT, watch-and-wait ve cerrahi kararları evreleme, MR bulguları ve tümör konseyi ile kişiye özel verilir.