Anorectal function after modern conformal radiation therapy for prostate cancer: a pilot study

Area of Science:

• Oncology
• Gastroenterology
• Radiation Oncology

Background:

• Prostate cancer radiotherapy aims to eradicate tumors while minimizing side effects.
• Modern radiotherapy techniques have improved precision but potential long-term sequelae require ongoing evaluation.

Purpose of the Study:

• To assess the impact of radiotherapy on bowel habits and anorectal function in prostate cancer patients.
• To quantify changes in anal sphincter pressure, rectal capacity, and sensory function post-treatment.

Main Methods:

• Prospective study of 10 prostate cancer patients treated with external beam radiotherapy or a combination of external beam and brachytherapy.
• Patient interviews to assess bowel dysfunction, endoscopic evaluation for proctitis, and anorectal manometry compared to age-matched controls.

Main Results:

• Half of the patients reported bowel disturbances including urgency, incontinence, and soiling.
• Endoscopy revealed mild radiation proctitis in patients.
• Significantly lower anal sphincter pressure, rectal capacity, and defecation urge threshold were observed in patients compared to controls.

Conclusions:

• Radiotherapy for prostate cancer, even with conformal techniques, can lead to persistent anorectal dysfunction and incontinence.
• Adverse effects on anal sphincter function, rectal reservoir capacity, and sensory function are attributed to radiation proctitis and nerve damage.
• Further advancements in radiotherapy are necessary to mitigate these functional disturbances.