Genetic, epigenetic and environmental factors in diverticular disease: systematic review.

BACKGROUND: Diverticulosis is a normal anatomical variant of the colon present in more than 70% of the westernized population over the age of 80. Approximately 3% will develop diverticulitis in their lifetime. Many patients present emergently, suffer high morbidity rates and require substantial healthcare resources. Diverticulosis is the most common finding at colonoscopy and has the potential for causing a significant morbidity rate and burden on healthcare. There is a need to better understand the aetiology and pathogenesis of diverticular disease. Research suggests a genetic susceptibility of 40-50% in the formation of diverticular disease. The aim of this review is to present the hypothesized functional effects of the identified gene loci and environmental factors. METHODS: A systematic literature review was performed using PubMed, MEDLINE and Embase. Medical subject headings terms used were: 'diverticular disease, diverticulosis, diverticulitis, genomics, genetics and epigenetics'. A review of grey literature identified environmental factors. RESULTS: Of 995 articles identified, 59 articles met the inclusion criteria. Age, obesity and smoking are strongly associated environmental risk factors. Intrinsic factors of the colonic wall are associated with the presence of diverticula. Genetic pathways of interest and environmental risk factors were identified. The COLQ, FAM155A, PHGR1, ARHGAP15, S100A10, and TNFSF15 genes are the strongest candidates for further research. CONCLUSION: There is increasing evidence to support the role of genomics in the spectrum of diverticular disease. Genomic, epigenetic and omic research with demographic context will help improve the understanding and management of this complex disease.

Characteristics of Early-Onset vs Late-Onset Colorectal Cancer: A Review.

Importance: The incidence of early-onset colorectal cancer (younger than 50 years) is rising globally, the reasons for which are unclear. It appears to represent a unique disease process with different clinical, pathological, and molecular characteristics compared with late-onset colorectal cancer. Data on oncological outcomes are limited, and sensitivity to conventional neoadjuvant and adjuvant therapy regimens appear to be unknown. The purpose of this review is to summarize the available literature on early-onset colorectal cancer. Observations: Within the next decade, it is estimated that 1 in 10 colon cancers and 1 in 4 rectal cancers will be diagnosed in adults younger than 50 years. Potential risk factors include a Westernized diet, obesity, antibiotic usage, and alterations in the gut microbiome. Although genetic predisposition plays a role, most cases are sporadic. The full spectrum of germline and somatic sequence variations implicated remains unknown. Younger patients typically present with descending colonic or rectal cancer, advanced disease stage, and unfavorable histopathological features. Despite being more likely to receive neoadjuvant and adjuvant therapy, patients with early-onset disease demonstrate comparable oncological outcomes with their older counterparts. Conclusions and Relevance: The clinicopathological features, underlying molecular profiles, and drivers of early-onset colorectal cancer differ from those of late-onset disease. Standardized, age-specific preventive, screening, diagnostic, and therapeutic strategies are required to optimize outcomes.

Protocol for the UK cohort study to investigate the prevention of parastomal hernia (the CIPHER study).

AIM: Abdominal surgery sometimes necessitates the creation of a stoma, which can cause future complications including parastomal hernia (PSH), an incisional hernia adjacent to and related to the stoma. PSH affects approximately 40% of patients within 2 years of stoma formation. Complications of PSH reduce a patient's quality of life and can be severe (e.g. bowel obstruction). PSHs are difficult to manage and can recur after surgical repair. Therefore, it is very important to prevent a PSH. Surgeons create stomas in different ways and both patient and surgical factors are believed to influence the development of PSH. The aim of the CIPHER study is to investigate the influence of different surgical techniques on the development of PSH. METHOD: The UK cohort study to investigate the prevention of parastomal hernia (the CIPHER study) aims to recruit 4000 patients undergoing elective or expedited surgery with the intention of forming an ileostomy or colostomy, irrespective of the primary indication for the planned surgery. For each patient, surgeons will describe their methods of trephine formation, mesh reinforcement of the stoma trephine, use of the stoma as a specimen extraction site and wound closure. The primary outcome will be incident PSH during follow-up, defined as symptoms of PSH (custom-designed questionnaire) and anatomical PSH, ascertained by independent reading of usual care CT scans. Secondary outcomes will include surgical site infection, the Comprehensive Complication Index, quality of life (EQ-5D-5L and SF-12), PSH repair and use of NHS resources. RESULTS: Results of the study will be submitted for publication in peer-reviewed journals. All publications relating to the results of CIPHER will use a corporate authorship, 'The CIPHER Study Investigators' with named writing committee members. CONCLUSION: The CIPHER study will be the first to investigate detailed surgical methods of stoma formation in a large, representative cohort of patients with a range of primary indications, both cancer and noncancer.

Root-cause analyses of missed opportunities for the diagnosis of colorectal cancer in patients with inflammatory bowel disease.

BACKGROUND: Colonoscopic surveillance in patients with inflammatory bowel disease (IBD) leads to earlier detection of colorectal cancer (CRC) and reduces CRC-associated mortality. However, it is limited by poor adherence in practice. AIM: To identify missed opportunities to detect IBD-associated CRC at our hospital METHODS: We undertook root-cause analyses to identify patients with missed opportunities to diagnose IBD-associated CRC. We matched patients with IBD-associated CRC to patients with CRC in the general population to identify differences in staging at diagnosis and clinical outcomes. RESULTS: Compared with the general population, patients with IBD were at increased risk of developing CRC (odds ratio 2.7 [95% CI 1.6-3.9], P < 0.001). The mean incidence of IBD-associated CRC between 1998 and 2019 was 165.4 (IQR 130.4-199.4) per 100 000 patients and has not changed over the last 20 years. Seventy-eight patients had IBD-associated CRC. Forty-two (54%) patients were eligible for CRC surveillance: 12% (5/42) and 10% (4/42) patients were diagnosed with CRC at an appropriately timed or overdue surveillance colonoscopy, respectively. Interval cancers occurred in 14% (6/42) of patients; 64% (27/42) of patients had a missed opportunity for colonoscopic surveillance where root-cause analyses demonstrated that 10/27 (37%) patients known to secondary care had not been offered surveillance. Four (15%) patients had a delayed diagnosis of CRC due to failure to account for previous colonoscopic findings. Seventeen (63%) patients were managed by primary care including seven patients discharged from secondary care without a surveillance plan. Matched case-control analysis did not show significant differences in cancer staging or 10-year survival outcomes. CONCLUSION: The incidence of IBD-associated CRC has remained static. Two-thirds of patients eligible for colonoscopic surveillance had missed opportunities to diagnose CRC. Surveillance programmes without comprehensive and fully integrated recall systems across primary and secondary care are set to fail.

Quality of life in restorative versus non-restorative resections for rectal cancer: systematic review.

BACKGROUND: Low rectal cancers could be treated using restorative (anterior resection, AR) or non-restorative procedures with an end/permanent stoma (Hartmann's, HE; or abdominoperineal excision, APE). Although the surgical choice is determined by tumour and patient factors, quality of life (QoL) will also influence the patient's future beyond cancer. This systematic review of the literature compared postoperative QoL between the restorative and non-restorative techniques using validated measurement tools. METHODS: The review was registered on PROSPERO (CRD42020131492). Embase and MEDLINE, along with grey literature and trials websites, were searched comprehensively for papers published since 2012. Inclusion criteria were original research in an adult population with rectal cancer that reported QoL using a validated tool, including the European Organization for Research and Treatment of Cancer QLQ-CR30, QLQ-CR29, and QLQ-CR38. Studies were included if they compared AR with APE (or HE), independent of study design. Risk of bias was assessed using the Risk Of Bias In Non-Randomized Studies of Interventions (ROBINS-I) tool. Outcomes of interest were: QoL, pain, gastrointestinal (GI) symptoms (stool frequency, flatulence, diarrhoea and constipation), and body image. RESULTS: Nineteen studies met the inclusion criteria with a total of 6453 patients; all papers were observational and just four included preoperative evaluations. There was no identifiable difference in global QoL and pain between the two surgical techniques. Reported results regarding GI symptoms and body image documented similar findings. The ROBINS-I tool highlighted a significant risk of bias across the studies. CONCLUSION: Currently, it is not possible to draw a firm conclusion on postoperative QoL, pain, GI symptoms, and body image following restorative or non-restorative surgery. The included studies were generally of poor quality, lacked preoperative evaluations, and showed considerable bias in the data.

Major surgery induces acute changes in measured DNA methylation associated with immune response pathways.

Surgery is an invasive procedure evoking acute inflammatory and immune responses that can influence risk for postoperative complications including cognitive dysfunction and delirium. Although the specific mechanisms driving these responses have not been well-characterized, they are hypothesized to involve the epigenetic regulation of gene expression. We quantified genome-wide levels of DNA methylation in peripheral blood mononuclear cells (PBMCs) longitudinally collected from a cohort of elderly patients undergoing major surgery, comparing samples collected at baseline to those collected immediately post-operatively and at discharge from hospital. We identified acute changes in measured DNA methylation at sites annotated to immune system genes, paralleling changes in serum-levels of markers including C-reactive protein (CRP) and Interleukin 6 (IL-6) measured in the same individuals. Many of the observed changes in measured DNA methylation were consistent across different types of major surgery, although there was notable heterogeneity between surgery types at certain loci. The acute changes in measured DNA methylation induced by surgery are relatively stable in the post-operative period, generally persisting until discharge from hospital. Our results highlight the dramatic alterations in gene regulation induced by invasive surgery, primarily reflecting upregulation of the immune system in response to trauma, wound healing and anaesthesia.

Factors affecting local regrowth after watch and wait for patients with a clinical complete response following chemoradiotherapy in rectal cancer (InterCoRe consortium): an individual participant data meta-analysis.

BACKGROUND: In patients with rectal cancer who achieve clinical complete response after neoadjuvant chemoradiotherapy, watch and wait is a novel management strategy with potential to avoid major surgery. Study-level meta-analyses have reported wide variation in the proportion of patients with local regrowth. We did an individual participant data meta-analysis to investigate factors affecting occurrence of local regrowth. METHODS: We updated search results of a recent systematic review by searching MEDLINE and Embase from Jan 1, 2016, to May 5, 2017, and used expert knowledge to identify published studies reporting on local regrowth in patients with rectal cancer managed by watch and wait after clinical complete response to neoadjuvant chemoradiotherapy. We restricted studies to those that defined clinical complete response using criteria equivalent to São Paulo benchmarks (ie, absence of residual ulceration, stenosis, or mass within the rectum on clinical and endoscopic examination). The primary outcome was 2-year cumulative incidence of local regrowth, estimated with a two-stage random-effects individual participant data meta-analysis. We assessed the effects of clinical and treatment factors using Cox frailty models, expressed as hazard ratios (HRs). From these models, we derived percentage differences in mean θ as an approximation of the effect of measured covariates on between-centre heterogeneity. This study is registered with PROSPERO, number CRD42017070934. FINDINGS: We obtained individual participant data from 11 studies, including 602 patients enrolled between March 11, 1990, and Feb 13, 2017, with a median follow-up of 37·6 months (IQR 25·0-58·7). Ten of the 11 datasets were judged to be at low risk of bias. 2-year cumulative incidence of local regrowth was 21·4% (random-effects 95% CI 15·3-27·6), with high levels of between-study heterogeneity (I2=61%). We noted wide between-centre variation in patient, tumour, and treatment characteristics. We found some evidence that increasing cT stage was associated with increased risk of local regrowth (random-effects HR per cT stage 1·40, 95% CI 1·00-1·94; ptrend=0·048). In a subgroup of 459 patients managed after 2008 (when pretreatment staging by MRI became standard), 2-year cumulative incidence of local regrowth was 19% (95% CI 13-28) for stage cT1 and cT2 tumours, 31% (26-37) for cT3, and 37% (21-60) for cT4 (random-effects HR per cT stage 1·50, random-effects 95% CI 1·03-2·17; ptrend=0·0330). We estimated that measured factors contributed 4·8-45·3% of observed between-centre heterogeneity. INTERPRETATION: In patients with rectal cancer and clinical complete response after chemoradiotherapy managed by watch and wait, we found some evidence that increasing cT stage predicts for local regrowth. These data will inform clinician-patient decision making in this setting. Research is needed to determine other predictors of a sustained clinical complete response. FUNDING: None.

Personalized management of elderly patients with rectal cancer: Expert recommendations of the European Society of Surgical Oncology, European Society of Coloproctology, International Society of Geriatric Oncology, and American College of Surgeons Commission on Cancer.

With an expanding elderly population and median rectal cancer detection age of 70 years, the prevalence of rectal cancer in elderly patients is increasing. Management is based on evidence from younger patients, resulting in substandard treatments and poor outcomes. Modern management of rectal cancer in the elderly demands patient-centered treatment, assessing frailty rather than chronological age. The heterogeneity of this group, combined with the limited available data, impedes drafting evidence-based guidelines. Therefore, a multidisciplinary task force convened experts from the European Society of Surgical Oncology, European Society of Coloproctology, International Society of Geriatric Oncology and the American College Surgeons Commission on Cancer, with the goal of identifying the best practice to promote personalized rectal cancer care in older patients. A crucial element for personalized care was recognized as the routine screening for frailty and geriatrician involvement and personalized care for frail patients. Careful patient selection and improved surgical and perioperative techniques are responsible for a substantial improvement in rectal cancer outcomes. Therefore, properly selected patients should be considered for surgical resection. Local excision can be utilized when balancing oncologic outcomes, frailty and life expectancy. Watch and wait protocols, in expert hands, are valuable for selected patients and adjuncts can be added to improve complete response rates. Functional recovery and patient-reported outcomes are as important as oncologic-specific outcomes in this age group. The above recommendations and others were made based on the best-available evidence to guide the personalized treatment of elderly patients with rectal cancer.

A case report of squamous cell carcinoma in a suprapubic urinary catheter tract: surgical excision and simultaneous colostomy formation.

Squamous cell carcinoma (SCC) arising from a suprapubic cystostomy tract is a rare complication of long-term suprapubic catheterization (SPC). A 53-year-old man with paraplegia secondary to spina bifida presented with a painful granulomatous lesion around his SPC site that was being treated with silver nitrate cauterization in the community. Consequently, he developed a sacral pressure sore due to reduced mobility from the pain. He also had increasing difficulties with defaecation secondary to his spina bifida. His sacral pressure sore was secondary to a cryptoglandular fistula with coccygeal osteomylelitis. Post-operative pathology revealed infiltrative SCC involving full thickness of the specimen from skin to the bladder wall with clear surgical margins. We describe the first case requiring a simultaneous suprapubic tract SCC excision and colostomy formation. We recommend early investigation of lesions arising from a long-term suprapubic tract especially in patients with spinal cord injuries or congenital defects.

Transperineal rectocele repair: a systematic review.

BACKGROUND: Transperineal rectocele repairs, either as isolated fascial repair or in combination with mesh augmentation, are hypothesized to reduce the risk of complications compared with alternative techniques. AIM: The aim of this study was to ascertain long-term success and complication rates following transperineal rectocele repairs. METHOD: A literature search of PubMed and Embase was performed using the terms 'transperineal rectocele', 'rectocele', 'transperineal' and 'repair'. Prospective studies, case series and retrospective case note analyses from 1 January 1994 to 1 December 2016 were included. Those that detailed outcomes of the transperineal approach or compared it to transanal/transvaginal approaches were included. The main outcome measures were reported complications and functional outcome scores. RESULTS: A total of 14 studies were included. Of 566 patients, 333 (58.8%) underwent a transperineal rectocele repair and 220 (41.2%) a transanal repair. Complications were identified in 27 (12.3%) of the 220 transanal repairs and in 41 (12.3%) of the 333 transperineal repairs. A significant complication following transperineal repair was noted in eight studies. There are not enough data to make a reliable comparison between mesh and non-mesh transperineal repairs or to compare biological and synthetic mesh use. LIMITATIONS: Outcome reporting differed between studies, precluding a full meta-analysis. CONCLUSION: Transperineal rectocele repair offers an effective method of symptom improvement and appears to have a similar complication rate as transanal rectocele repair. Concomitant use of synthetic and biological mesh augmentation is becoming more common; however, high-quality comparative data are lacking, so a direct comparison between surgical approaches is not yet possible.

A systematic review of new treatments for cryptoglandular fistula in ano.

AIM: In 2007 the ACPGBI published a position statement on the management of cryptoglandular fistula in ano. Over the last seven years a number of new treatments have been developed and the aim of this systematic review was to assess their effectiveness. METHOD: A systematic review of all English language literature relevant to novel treatment strategies for cryptoglandular fistula in ano, published between 1 January 2007 and 31 Dec 2014 was carried out using MEDLINE (PubMed and Ovid), EMBASE (Ovid) and the Cochrane Library of Systematic Reviews/Controlled Trials for relevant literature. Technical notes, commentaries, letters and meeting abstracts were excluded. The different treatments were assessed with regards to fistula closure rate in relation to length of follow up and reported complications. RESULTS: Seventy potential articles published between 1 January 2007 and 31 December 2014 were identified from the initial literature search. Twenty-one articles were included for final analysis although only two were randomized controlled trials, the remainder being retrospective or prospective series. CONCLUSION: This systematic review has demonstrated that whilst there have been technological advances to treat complex cryptoglandular fistula in ano, these are in an early stage of evolution and although early results were promising they are difficult to reproduce. Longer follow up data is not currently available and these treatments should not be introduced without further evidence.

Retro-rectus repair of complex incisional hernia leads to low recurrence rate.

BACKGROUND: To assess the outcome of retro-rectus repair of complex abdominal wall repair (CAWR) in a single institution in relation to the use of biologic and synthetic mesh. METHOD: A retrospective review was undertaken of complex abdominal wall repairs performed by a single surgical team, assessing the outcome of the retro-rectus repair and factors affecting the outcome. RESULTS: Between 2007 and 2013, 57 (33 male) patients underwent CAWR retro-rectus repair. The material used was assessed as either synthetic or biologic (cross-linked porcine dermal collagen). The Ventral Hernia Working Group grades were similar between groups of patients having a repair with synthetic and biologic mesh. Median follow-up in the synthetic group was 18 months (1-80.5) and 18.4 months (0.5-70.7) in the biologic group. There was no statistical difference in seroma, wound infection or haematoma rates. No fistulae occurred in either group. Overall recurrence was 3.4% and there was no statistical difference between groups. CONCLUSION: The retro-rectus repair technique is associated with a low rate of recurrence and is now the technique of choice. The choice of material, biologic or synthetic, in Ventral Hernia Working Group grades 1-3 remains controversial.

Parastomal hernia following cystectomy and ileal conduit urinary diversion: a systematic review.

PURPOSE: The natural history of development of Parastomal hernia (PH) following cystectomy and ileal conduit diversion is poorly understood. The aim of this study was to systematically review the frequency and risk factors of PH following ileal conduit diversion. METHODS: A systematic review of literature was performed and the Cochrane, EMBASE and PubMed databases were searched from 1st January 1985 to 30th April 2016. All articles reporting occurrence of PH following cystectomy and ileal conduit diversion were analysed. The primary outcome measure was the frequency of development of PH. Secondary outcome measures were risk factors for PH development, complications of PH, frequency of PH repair and recurrence of PH. RESULTS: Twelve articles of the 63 originally identified were analysed. Sample sizes ranged from 36 to 1057 patients with a pooled total of 3170 undergoing ileal conduit surgery. Age at the time of surgery ranged from 31 to 92 years. Of the 3170 patients who underwent ileal conduit surgery, 529 patients (17.1%) developed a PH based on either clinical examination or cross sectional imaging. Female gender, high BMI, low preoperative albumin and previous laparotomy were significantly associated with the development of PH in two studies. Repair of PH was offered to 8-75% of patients. The rate of recurrence following repair of PH was reported to range from 27 to 50%. CONCLUSION: A PH is frequent following cystectomy and ileal conduit urinary diversion. The diagnosis of a PH depends upon duration of clinical follow-up and the use of cross-sectional imaging. The recurrence rates following the repair of a PH remain substantial.

Repair of Perineal Hernia Following Abdominoperineal Excision with Biological Mesh: A Systematic Review.

INTRODUCTION: Perineal hernia (PerH) following abdominoperineal excision (APE) procedure is a recognized complication. PerH was considered an infrequent complication of APE procedure; however, PerH rates of up to 45% have been reported in recent publications following a laparoscopic APE procedure. Various methods of repair of PerH with the use of synthetic meshes or myocutaneous flap have been described, although there is no general agreement on an optimal strategy. The use of biological meshes for different operations is growing in popularity, and these have been promoted as being superior and safer when compared to synthetic meshes. Although the use of biologics is becoming popular claims of better outcomes are largely unsupported by evidence. The aim of this systematic review is to evaluate the currently available evidence supporting the use of biologic or biosynthetic meshes for the repair of PerH that develop following an APE. METHODS: A systematic review of all English language literature relevant to repair of PerH following APE with biologic or biosynthetic mesh published between January 1, 2000 and July 31, 2016 was carried out using MEDLINE, EMBASE, and the Cochrane Library of Systematic Reviews for relevant literature. Searches were performed using a combination of Medical Subject Headings (MeSH) terms and text words "PerH," "APE," "morbidity," "biologics," "biosynthetic," and "hernia." Studies in which the use of biological meshes was not reported were excluded from the review. Various outcome measures, including operative technique, complication rates, recurrence rates, type of mesh, management of recurrences, and risk factors, were extracted. Oxford Centre for Evidence-based Medicine - Levels of Evidence (March 2009) was used to assess the quality of evidence. RESULTS: The systematic review of the literature identified three case reports, four case series, and one pooled analysis that were included in the final review. Overall, these studies were of poor quality providing level 4 evidence. Various different approaches and techniques of repair of PerH were described; however, it was difficult to extract information with regard to the primary and secondary outcome measures. CONCLUSION: There is no general agreement to the optimal operative strategy to repair PerH following an APE. There is insufficient evidence to recommend any specific operative approach or repair technique for PerH following an APE.

Biologic Mesh Reconstruction of the Pelvic Floor after Extralevator Abdominoperineal Excision: A Systematic Review.

INTRODUCTION: The aim of this review is to provide an overview of the evidence for the use of biologic mesh in the reconstruction of the pelvic floor after extralevator abdominoperineal excision of the rectum (ELAPE). METHODS: A systematic search of PubMed was conducted using the search terms: "ELAPE," "extralevator abdominoperineal excision of rectum," or "extralevator abdominoperineal resection." The search yielded 17 studies. RESULTS: Biologic mesh was used in perineal reconstruction in 463 cases. There were 41 perineal hernias reported but rates were not consistently reported in all studies. The most common complications were perineal wound infection (n = 93), perineal sinus and fistulae (n = 26), and perineal haematoma or seroma (n = 11). There were very few comparative studies, with only one randomized control trial (RCT) identified that compared patients undergoing ELAPE with perineal reconstruction using a biological mesh, with patients undergoing a conventional abdominoperineal excision of the rectum with no mesh. There was no significant difference in perineal hernia rates or perineal wound infections between the groups. Other comparative studies comparing the use of biologic mesh with techniques, such as the use of myocutaneous flaps, were of low quality. CONCLUSION: Biologic mesh-assisted perineal reconstruction is a promising technique to improve wound healing and has comparable complications rates to other techniques. However, there is not enough evidence to support its use in all patients who have undergone ELAPE. Results from high-quality prospective RCTs and national/international collaborative audits are required.

Focusing the management of rectal cancer.

Rectal cancer treatment has undergone major changes over the last 15 years with a focus on individualized care based around MRI assessment of the relationship of the tumour to the mesorectal fascia, improved surgical techniques and targeted use of pre-operative oncological therapies in patients with locally advanced disease. The recognition that some tumours responded completely to pre-operative chemoradiotherapy, and the selective use of a non-operative policy has led to a quest to further identify those patients and their tumour in whom this approach could be used, irrespective of MRI stage. With no clear patient factors identified, the tumour and its gene expression has become a target for research to identify individual single-nucleotide polymorphisms, which may indicate a response to specific treatment, or not. To date some agents have been identified and trialed, such as cetuximab, with individual tumours being assessed for response allowing directed treatment. The reviewed paper by Sebio and colleagues report a study that links polymorphisms in the DNA repair gene XRCC1 with response to neoadjuvant 5-Fluorouracil treatment in rectal cancer patients. However, genetic heterogeneity alone may not explain the variations of drug response and environmental factors may lead to epigenetic effects and therefore alter responses. Therefore whilst this study demonstrates the impact of different single nucleotide polymorphisms (SNPs), it is only one step forward, but perhaps a step in the right direction.

Anal Sphincter Augmentation Using Biological Material.

INTRODUCTION: The aim of this review is to provide an overview of the use of biological materials in the augmentation of the anal sphincter either as part of an overlapping sphincter repair (OSR) or anal bulking procedure. METHODS: A systematic search of PubMed was conducted using the search terms "anal bulking agents," "anal sphincter repair," or "overlapping sphincter repair." Five studies using biological material as part of an overlapping sphincter repair (OSR) or as an anal bulking agent were identified. RESULTS: 122 patients underwent anal bulking with a biological material. Anorectal physiology was conducted in 27 patients and demonstrated deterioration in maximum resting pressure, and no significant change in maximum squeeze increment. Quality of life scores (QoLs) demonstrated improvements at 6 weeks and 6 months, but this had deteriorated at 12 months of follow up. Biological material was used in 23 patients to carry out an anal encirclement procedure. Improvements in QoLs were observed in patients undergoing OSR as well as anal encirclement using biological material. Incontinence episodes decreased to an average of one per week from 8 to 10 preoperatively. CONCLUSION: Sphincter encirclement with biological material has demonstrated improvements in continence and QoLs in the short term compared to traditional repair alone. Long-term studies are necessary to determine if this effect is sustained. As an anal bulking agent the benefits are short-term.