Efficacy and safety of sacral nerve modulation for faecal incontinence after pelvic radiotherapy

To assess the efficacy and safety of sacral nerve modulation (SNM) in patients with faecal incontinence (FI) after pelvic radiotherapy in comparison with results of SNM for FI related to other conditions.

Prospectively collected data from patients who underwent SNM therapy between January 2010 and December 2015 at 7 tertiary colorectal units were reviewed retrospectively. Patients with FI following pelvic radiotherapy were identified and matched (1:2) for age and sex with 38 patients implanted over the same period for FI without previous radiotherapy. The treatment was considered favourable if the patient reported any therapeutic benefit from SNM, had no further complaints or interventions and did not consider stopping the treatment. Long-term results, surgical revision and definitive explantation rates were compared.

Among 352 patients who received a permanent SNM implant, 19 (5.4%) had FI following pelvic radiotherapy. After a mean follow-up of 3.5 ± 1.9 years, the cumulative successful treatment rates were similar between the groups (p = 0.60). For patients with FI following pelvic radiotherapy, the cumulative success rates were 99.4% [85.4-99.8], 96.7% [78.1-99.6], 91.7% [70.4-98.1] and 74.6% [48.4-94.8] at 1, 2, 3 and 5 years respectively. The revision and definitive explantation rates for infection did not differ significantly.

The long-term success rate of SNM for FI after pelvic radiotherapy is similar to that of SNM for FI related to other more frequent conditions. Our study suggests that FI after pelvic radiotherapy could be improved with SNM without an increased risk of complication.