Long-term effect of preoperative radiation therapy on anorectal function

Area of Science:

• Oncology
• Gastroenterology
• Surgical Oncology

Background:

• Preoperative radiotherapy is used for rectal cancer to improve local control.
• Its impact on long-term anorectal function is not well-documented.

Purpose of the Study:

• To assess the late effects of short-course, high-dose preoperative radiotherapy on anorectal function following low anterior resection for rectal cancer.

Main Methods:

• A randomized study followed 64 patients (21 radiotherapy, 43 surgery alone) for a mean of 14 years.
• Assessments included quality-of-life questionnaires, clinical examination, anorectal manometry, and endoanal ultrasound.

Main Results:

• Radiotherapy significantly increased fecal incontinence (57% vs 26%) and soiling (38% vs 16%).
• Irradiated patients had more bowel movements, lower resting and squeeze pressures, and more anal sphincter scarring.
• No difference in overall quality of life, but incontinence lowered scores.

Conclusions:

• Short-course radiotherapy, particularly when irradiating anal sphincters, permanently impairs anorectal function.
• This leads to increased and persistent gastrointestinal symptoms in rectal cancer patients.