[Sexual functions after treatment for rectal cancer: impact of doses in autonomic pelvic nerves]

Purpose: Prospective evaluation of sexual function after treatment of rectal cancer and identification of predictive factors.

Patients and methods: Thirty-three patients were treated with curative intent by chemoradiation and surgery for localized rectal adenocarcinoma. Sexual toxicity was assessed four times (before treatment and at 2, 6 and 12 months) using validated questionnaires: QLQ C30 and EORTC CR38 for all, simplified IIEF for men and FSFI for women. A correlation was sought between the toxicity and clinical and dosimetric parameters by Fisher and Mann-Whitney tests.

Results: In men, erections and sexual satisfaction decreased significantly from the acute phase and then stabilized (respective scores of 84.5 and 86/100 in the initial phase, 66 and 70.4 at the end of radiotherapy, 70 and 70 at 6 months and 68.5 and 70 at 12 months). For women, the changes were not significant. This study confirms some risk factors for sexual toxicity already mentioned (original function, age, tumor volume) and highlights new (dose to the seminal vesicles and above all, doses to pelvic autonomic plexus).

Conclusion: Sexual effects of combined treatment of rectal cancer have only recently been described but remain undervalued and poorly understood. The impact of the autonomic pelvic plexus doses is a completely new data that could be extended in the development of intensity-modulated radiotherapy.