Risk of colorectal adenomas and cancer in monoallelic carriers of MUTYH pathogenic variants: a single-centre experience.

PURPOSE: The carrier frequency of MUTYH pathogenic variants in the population may be as high as one in 45. Some studies have found an increased risk of colorectal cancer (CRC) in monoallelic carriers of MUTYH pathogenic variants, but the role of early surveillance colonoscopy is not conclusive. This study aimed to assess the outcomes of colonoscopy surveillance in MUTYH carriers. METHODS: Patients, with a monoallelic pathogenic variant in MUTYH, found at cascade testing, were identified from the St Mark's Hospital Polyposis Registry database. Findings at surveillance colonoscopy were reviewed. RESULTS: Two hundred and forty-nine carriers were identified, of whom 125 had undergone at least one surveillance colonoscopy. Twenty-eight patients (22%) developed at least one adenoma; all adenomas had low-grade dysplasia (LGD). The median age at first colonoscopy was 36 years (range 16-75 years). The median age at first adenoma detection was 43 years (range 22-75 years). The cumulative incidence of adenoma development by age 30, 40, 50, 60 and 70 years was 3.2%, 8.8%, 15.2%, 18.4% and 20.8%, respectively. No CRCs were observed. CONCLUSIONS: Our cohort of monoallelic carriers of MUTYH pathogenic variants is a relatively younger group than adults entering population screening colonoscopy, but a high adenoma rate was not observed. No CRCs were detected, suggesting that current guidance that these individuals should be managed in the same way as the general population is reasonable.

MUTYH-associated polyposis - colorectal phenotype and management.

AIM: The aim was to determine the presentation, management and outcomes of MUTYH-associated polyposis (MAP). METHOD: A prospectively maintained database was used to identify patients with MAP. Demographic data and data on germline mutation, surgical management, histopathology of tumours and endoscopic surveillance were collected. RESULTS: In all, 134 patients with MAP were identified. The majority presented symptomatically (n = 83). Sixty-eight patients developed cancer (seven synchronous, 12 metachronous). The median age at diagnosis of first colorectal cancer was 47 years (range 33-74 years). Cancers occurred in the context of a few adenomas (< 10). The majority of patients (n = 108) had surgery as the first line management. One patient received palliative care. Twenty-five patients had endoscopic surveillance as first line management; no cancers occurred in this group. Patients who had segmental resection and postoperative surveillance still appeared to be at risk of metachronous cancer (5/30, 17%). CONCLUSIONS: MUTYH testing should be considered even in the context of cancers occurring with fewer than 10 adenomas. In cases of primary colorectal cancers, extended surgery should be considered if patients do not have access to high quality endoscopic surveillance postoperatively. For some patients, endoscopic therapy is an appropriate and safe option in expert hands.

Safety and efficacy of laparoscopic near-total colectomy and ileo-distal sigmoid anastomosis as a modification of total colectomy and ileorectal anastomosis for prophylactic surgery in patients with adenomatous polyposis syndromes: a comparative study.

AIM: Colectomy in patients with adenomatous polyposis (AP) syndromes demands good oncological and surgical outcome. Total colectomy with ileorectal anastomosis (TC-IRA) is one surgical option for these patients. Anastomotic leakage rates of 11% have been reported following TC-IRA. Ileo-distal sigmoid anastomosis (IDSA) is a recent modification of our practice. Our aim was to compare postoperative outcome in patients with AP following near-total colectomy with IDSA (NT-IDSA) and TC-IRA at a single institution. METHOD: A prospectively maintained database was reviewed to identify patients with AP who underwent laparoscopic NT-IDSA and TC-IRA. Patient demographics, early morbidity and mortality and outcome of endoscopic surveillance were evaluated. RESULTS: A total of 191 patients with AP underwent laparoscopic colectomy between 2006 and 2017, of whom 139 (72.8%) underwent TC-IRA and 52 (27.2%) NT-IDSA. The median age at surgery in the TC-IRA and NT-IDSA groups was 20 years (IQR 17-45) and 27 years (IQR 19-50), respectively. Grade II complications were comparable between the two groups. There were no anastomotic leakages in the NT-IDSA group compared with 15 (10.8%) in the TC-IRA group (P = 0.0125) and no reoperation in the NT-IDSA group compared with 17 (12.2%) in the TC-IRA group (P = 0.008). The frequency of polypectomies per flexible sigmoidoscopy was comparable between the two groups. CONCLUSION: This study demonstrates that laparoscopic NT-IDSA for polyposis is associated with a significant improvement in anastomotic leakage rates and surgical outcome. It is too soon to tell whether NT-IDSA alters the need for further intervention, either endoscopic polypectomy or further surgery.

Straight to test. Results of a pilot study in a hospital serving an inner city population.

OBJECTIVE: The main aims of the study were to determine the frequency with which two-week wait (2ww) referrals for colorectal cancer (CRC) could proceed directly to straight to test (STT), and the potential improvement in time to diagnosis. METHOD: A telephone interview was attempted in all 2ww referrals not requiring an advocate and under 80 years. Data were assessed according to a test protocol, and where indicated a potential slot for the appropriate investigation was recorded (virtual test). All patients proceeded to clinic, following which differences in time from GP referral to virtual compared with actual requested test, and any discrepancies between virtual and requested tests were analysed. RESULTS: Between 8th January and 16th February 2007, there were 42 2ww referrals. Twenty-one patients were contacted, of whom 14 were suitable for STT: 13 virtual colonoscopies and one CT scan were booked. Following out-patient consultation, eight colonoscopies; three flexible sigmoidoscopies, one barium enema, and two CT scans were actually booked. There was a difference of 15.5 days between the median times of the virtual and actual test. During this 6-week period a total of nine patients were diagnosed with CRC, of whom three were referred via the 2ww pathway, but none were suitable for STT. CONCLUSIONS: This 'straight to test' pilot study suggests a potential strategy for reducing the time to diagnosis and therefore first treatment of those identified with CRC, and offers a methodology for individual hospitals to assess their suitability to employ such a strategy.