Colonic J-pouch function in rectal cancer patients - Impact of adjuvant chemoradiotherapy

PURPOSE: The colonic J-pouch technique of reconstruction optimizes function al outcome after proctectomy with coloanal anastomosis. However, the impact of adjuvant chemoradiation therapy on pouch function in rectal cancer pati ents has not been investigated. METHODS: From January 1994 to December 1999 , 74 patients with midrectal or low rectal tumors (less than 10 cm from the anal verge) under-went a proctectomy with coloanal anastomosis with coloni c J-pouch reconstruction. Chemoradiation was offered in patients with Stage II and III disease. Radiation therapy was administered using a four-field technique including the anal canal, for a total close of 50.4 Gy (1.8 Gy/fr action/day). Fifteen patients (20 percent) died with metastatic disease, fi ve (6.8 percent) died of other causes without evidence of recurrence, and f ive (6.8 percent) were lost to follow-up. In addition, two patients had loc al recurrence (2.7 percent) at the time of follow-up. Forty-five of 47 elig ible patients (96 percent) responded to a questionnaire designed to evaluat e specifically the degree of continence and pouch evacuation. RESULTS: The mean age of patients was 68.9 (range, 42-88) years and the mean duration of follow-up was 28.8 (range, 1-69) months. There were 28 patients in the sur gery alone group and 17 patients who received either preoperative (13) or p ostoperative (4) adjuvant chemoradiation therapy. Patients in the surgery a lone group had a significantly better degree of continence (mean +/- standa rd deviation continence score: 18.1 +/- 2.9 vs. 13.3 +/- 4.1, P < 0.001) an d were less likely to experience evacuatory problems (mean +/- standard dev iation evacuation score: 21.3 +/- 3.7 vs. 16.4 +/- 3.5, P < 0.001). Use of a pad was more frequent in the chemoradiation therapy than in the surgery a lone group (53 vs. 18 percent, P = 0.02). The incidence after functional di sorders was also more frequent in the irradiated group of patients, inconti nence to gas (76 vs. 43 percent, P = 0.03), to liquid stool (64 vs. 25 perc ent, P = 0.01), and to solid stool (47 vs, 11 percent, P = 0.01). Moreover, irradiated patients reported more frequent pouch-related specific problems , such as clustering (82 vs. 32 percent, P = 0.001), and sensation of incom plete evacuation (82 vs. 32 percent, P = 0.001). Finally, regression analys is demonstrated that radiation-induced sphincter dysfunction was progressiv e over time. CONCLUSIONS: Both preoperative and postoperative chemoradiatio n therapy adversely affects continence and evacuation in patients with colo nic J-pouch. Because radiation-induced damage to the normal tissues is know n to be cumulative over time, long-term progressive dysfunction of the anal sphincter and neorectum, are causes of concern. Consideration should be gi ven to excluding the anal canal from the field of irradiation in patients w ith Stage II and III rectal cancer, whenever a sphincter-preserving procedu re is planned.