Long-Term Anorectal Dysfunction After Postoperative Radiotherapy for Rectal Cancer

• DOI: 10.1007/s10350-005-0049-1
• Publication Date: 2005-06-01T18:22:12Z
• Authors: Lilli Lundby; Klaus Krogh; Vagn J. Jensen; Per Gandrup; Niels Qvist; Jens Overgaard; Soren Laurberg
• Keywords: Questionnaires; Male; Manometry; Endoscopy, Gastrointestinal; Statistics, Nonparametric; Endosonography; 03 medical and health sciences; 0302 clinical medicine; Humans; Prospective Studies; Gastrointestinal Transit; Sigmoidoscopy; Aged; Retrospective Studies; Aged, 80 and over; Analysis of Variance; Rectal Neoplasms; Anastomosis, Surgical; Middle Aged; Combined Modality Therapy; 3. Good health; Treatment Outcome; Female; Radiotherapy, Adjuvant; Fecal Incontinence

Adjuvant radiotherapy in the treatment of rectal cancer has been shown to increase long-term morbidity causing severe anorectal dysfunction with physiologic changes whose interaction remains poorly understood. This study examines long-term anorectal morbidity from adjuvant postoperative radiotherapy.In a prospective study, patients with Dukes B or C rectal carcinoma were randomized to postoperative radiotherapy or no adjuvant treatment after anterior resection. The long-term effect of radiotherapy on anorectal function in a subset of surviving patients was assessed from a questionnaire on subjective symptoms and from physiology laboratory evaluation and flexible sigmoidoscopy.Twelve of 15 patients (80 percent) treated with radiotherapy had increased bowel frequency compared with 3 of the 13 patients (23 percent) who did not have radiation therapy (P = 0.003). The former group had loose or liquid stool more often (60 vs. 23 percent, P = 0.05), had fecal incontinence more often (60 vs. 8 percent, P = 0.004), and wore pad more often (47 vs. 0 percent, P = 0.004). They also experienced fecal urgency and were unable to differentiate stool from gas more often. Endoscopy revealed a pale and atrophied mucosa and telangiectasias in the irradiated patients. Anorectal physiology showed a reduced rectal capacity (146 vs. 215 ml, P = 0.03) and maximum squeeze pressure (59 vs. 93 cm H2O, P = 0.003) in the radiotherapy group. Impedance planimetry demonstrated a reduced rectal distensibility in these patients (P < 0.0001).Adjuvant postoperative radiotherapy after anterior resection causes severe long-term anorectal dysfunction, which is mainly the result of a weakened, less sensitive anal sphincter and an undistensible rectum with reduced capacity.