In rectal adenomas, TEM has emerged as the procedure of choice because of its safety and low local recurrence rates. Especially compared to radical surgery, TEM has proven its safety [
22,
23]. However, possible adverse effects of TEM have to be addressed. The use of a rectoscope with a 4-cm diametre, introduced transanally, has lead to substantial scepticism regarding impact on anorectal functioning. In earlier studies, we already showed TEM to be superior to total mesorectal excision regarding post-operative defecation disorders, although this did not result in improved quality of life [
24]. In the present study, TEM resulted in improved faecal continence as measured by the FISI. This apparent paradox may be attributed to pre-operative tumour symptoms such as mucinous or bloody discharge, prolapse, tenesmi and/or urge, giving rise to incontinence-like symptoms. Post-operative improvement of continence was most significant in tumours within 7 cm from the dentate line but disappeared in our study in tumours above 7 cm from the dentate line. Kreis et al. [
25] performed manometric studies after TEM and found a significant reduction in anal resting pressure 1 year post-operative and a temporary reduction in anal squeezing pressure, resulting in a temporary rise in urge–incontinence. Kennedy et al. [
26] found a significant reduction in anal resting pressure 6 weeks after TEM. This reduction was significantly correlated with duration of the procedure, but mean continence score was not changed after TEM. Both of the above studies however did not use validated questionnaires on faecal continence, and therefore comparison with our study is difficult. Cataldo et al. [
17] reported on the impact of TEM on functional outcome and incontinence-specific quality of life using the same questionnaires. No significant alteration was found in faecal continence after TEM. The discrepancy between both studies may be explained by the relative short interval between the TEM procedure and post-operative questioning of 6 weeks in the Cataldo series. Also, in his study, indications for TEM were heterogeneous which may have influenced results. The positive effect of TEM on faecal continence in our series may be explained by the differences in pre-operative FISI score between both studies (10 versus 2.4), depicting more continence problems among the patients in our series. Another explanation may be the differences in tumour distance from the dentate line (present series median 7 cm, Cataldo series 11 cm). Also, in our series, tumours were larger (median 20 cm
2 versus 8.75 cm
2). Because tumours were larger in our series, more extensive resections were performed, often in tumours located within the sphincter apparatus. These latter resections were already shown to influence rectoinhibitory reflex, reflex sphincter contraction, rectal sensitivity and compliance [
16]. Further analysis within our series upon this issue showed only tumour distance from the dentate line of less than 7 cm to be a significant contributing factor. These results however are based upon low number of patients and therefore solid conclusions cannot be drawn. Although in our study TEM resulted in a significant improvement in continence, the post-operative FISI was still worse compared to the Cataldo series (7 versus 2.4). Regarding quality of life, Cataldo found TEM was of no significant influence. In our series, mean general quality of life score from the patients’ perspective, EQ-VAS, was significantly higher after TEM. This improvement could not be explained by improved FISI scores but probably by lower pre-operative EQ-VAS scores as compared to healthy controls. Another explanation may be the rejoice phenomena, that is, patients are relieved the tumour has been excised, and in most cases an adenoma was found [
27]. However, because of the low number of invasive carcinomas in our series this is purely theoretical. The societal value of general quality of life, EQ-5D, remained unchanged. Measuring quality of life using the FIQL questionnaires resulted in a significant improvement in two of the four FIQL domains (embarrassment and lifestyle). Moreover, the domains of lifestyle, coping and behaviour and embarrassment were all significantly correlated with the FISI.
In conclusion, how are these results to be interpreted? This study supports the hypothesis that rectal tumours give rise to incontinence-like symptoms, especially in low-lying rectal tumours. After the tumour is excised using the TEM technique, faecal continence improves. TEM itself does not improve continence but also does not deteriorate faecal continence. Mean quality of life from the patients’ perspective following TEM is improved.
Based on, as we know, the only two studies addressing anorectal functioning and quality of life after TEM in one study, it can be concluded that TEM does not impair faecal continence. Also, quality of life is not negatively influenced by the TEM procedure itself, and therefore TEM is the procedure of choice in all rectal adenomas.