Faecal incontinence following radiotherapy for prostate cancer:a systematic review

Background Faecal incontinence (FI) after radiotherapy is a known phenomenon, but has received little attention to date. This article aimed to review current knowledge on faecal incontinence related to radiotherapy for prostate cancer. Methods PubMed was searched for English-language articles published from January 1966 to December 2009 using the primary keywords ‘faecal incontinence’, ‘prostate cancer’ and ‘radiotherapy’. Prospective, retrospective and controlled trials reporting FI as a complication of radiotherapy for prostate cancer were included. The retrieved titles and abstracts were screened permissively and evaluated as to whether they satisfied the predefined inclusion and exclusion criteria. Results Nine hundred and ninety four articles were identified from the search. After step-wise review, 213 papers were selected for full article review of which 40 were selected for this review. The incidence of faecal incontinence following radiotherapy for prostate cancer varied from 1.6% to 58%. The mechanism of faecal incontinence was not entirely clear but it is most likely due to injury to the nerve plexus of the rectal muscular layer. Correlation between rectal dose–volume parameters and incidence is equivocal, although some studies suggest parameters confined to the lower rectum and/or anal canal may be of value to predict the extent of the injury and could be used as constraints in the dose planning process. Conclusions Interpretation of data is limited due to lack of large cohort studies with data on pre-treatment continence status and because variable instruments have been used to assess the severity of the condition. Well-designed prospective studies are needed to investigate dosimetric parameters focusing on the anal canal and sphincter apparatus. Considering the spatial distribution of radiation to the rectum may identify a more direct linkage between radiation damage and faecal incontinence

Management of patients with faecal incontinence

Faecal incontinence, defined as the involuntary loss of solid or liquid stool, is a common problem affecting 0.8–8.3% of the adult population. Individuals suffering from faecal incontinence often live a restricted life with reduced quality of life. The present paper is a clinically oriented review of the pathophysiology, evaluation and treatment of faecal incontinence. First-line therapy should be conservative and usually include dietary adjustments, fibre supplement, constipating agents or mini enemas. Biofeedback therapy to improve external anal sphincter function can be offered but the evidence for long-term effect is poor. There is good evidence that colonic irrigation can reduce symptoms and improve quality of life, especially in patients with neurogenic faecal incontinence. Surgical interventions should only be considered if conservative measures fail. Sacral nerve stimulation is a minimally invasive procedure with high rate of success. Advanced surgical procedures should be restricted to highly selected patients and only performed at specialist centres. A stoma should be considered if other treatment modalities fail

Molecular differences of adipose-derived mesenchymal stem cells between non-responders and responders in treatment of transphincteric perianal fistulas

Background: Injection of autologous adipose tissue (AT) has recently been demonstrated to be an efective and safe treatment for anal fstulas. AT mesenchymal stem cells (AT-MSCs) mediate the healing process, but the relationship between molecular characteristics of AT-MSCs of the injected AT and fstula healing has not been adequately studied. Thus we aimed to characterize the molecular and functional properties of AT-MSCs isolated from autologous AT injected as a treatment of cryptogenic high transsphincteric perianal fstulas and correlate these fndings to the healing process. Methods: 27 patients (age 45±2 years) diagnosed with perianal fstula were enrolled in the study and treated with autologous AT injected around the anal fstula tract. AT-MSCs were isolated for cellular and molecular analyses. The fstula healing was evaluated by MRI scanning after 6 months of treatment. AT-MSC phenotype was compared between responders and non-responders with respect to fstula healing. Results: 52% of all patients exhibited clinical healing of the fstulas as evaluated 6 months after last injection. Cultured AT-MSCs in the responder group had a lower short-term proliferation rate and higher osteoblast diferentiation potential compared to non-responder AT-MSCs. On the other hand, adipocyte diferentiation potential of AT-MSCs was higher in non-responder group. Interestingly, AT-MSCs of responders exhibited lower expression of infammatory and senescence associated genes such as IL1B, NFKB, CDKN2A, TPB3,TGFB1. Conclusion: Our data suggest that cellular quality of the injected AT-MSCs including cell proliferation, diferentiation capacity and secretion of proinfammatory molecules may provide a possible mechanism underlying fstula healing. Furthermore, these biomarkers may be useful to predict a positive fstula healing outcome