[Vulnerability of ileocoecal interposition pouch and colonic J-pouch to postoperative adjuvant radiotherapy]

The interposition of an ileocoecal segment has been introduced as an alternative procedure to impair the functional outcome following total mesorectal excision (TME). Up to now, there is no information concerning the effect of postoperative radiotherapy on the functional outcome of this method.

We compared functional outcome, anorectal physiology, and radiation therapy-related morbidity of 18 patients treated with TME und ileocoecal interposition (ICI) of which ten had postoperative radiotherapy, with 15 patients who had TME and colonic J-pouch (CJP) reconstruction of which 7 were subjected to radiotherapy.

Patients with no radiotherapy revealed a satisfying functional result with a similar median frequency of defecation of 4.25 (2-5) and 3 (2-6) and an incontinence-score of 2.8 (0-6) and 1.0 (0-2) after ICI and CJP, respectively. Median stool frequency (7 (2-11) (ICI) and 5 (2.5-11) (CJP)) and incontinence score (6 (0-12) (ICI) and 7 (6-12) (CJP)) were markedly increased in both groups after radiotherapy. Besides a reduced anal resting pressure, a lower compliance and a smaller volume of the neorectum were observed in the irradiated patients. A radiogenic injury which required surgery was seen in 4/10 patients after ICI. In three of these four patients the interposed ileocoecal segment was mainly affected. None of the patients treated with a CJP suffered a similar complication.

These data indicate that postoperative radiotherapy severely impairs the functional outcome after TME independent of the type of surgery used for reconstruction, and causes a significant morbidity after ICI.

Postoperative radiotherapy following TME should be indicated cautiously, and ICI should not be used if postoperative radiotherapy is intended.