Outcomes of screening and surveillance in people with two parents affected by colorectal cancers: experiences from the Familial Bowel Cancer Service.

BACKGROUND: The Familial Bowel Cancer Service at The Royal Melbourne Hospital was started in 1980 in order to offer bowel cancer screening services to those felt to be at a higher risk of CRC due to their family history, and upon registration in this service, patients gave consent for recording of their individual and familial medical history as pertaining to colorectal cancer in the FamBIS database. Using the FamBIS database, we sought to understand whether the subpopulation of individuals in whom both parents were diagnosed with colorectal cancer carried a higher risk of colorectal cancer or neoplastic polyps and should therefore undergo more intensive screening above that of the average-risk individual. METHODS: We conducted a single-centre retrospective cohort-study of adults (18 years of age and older) in the FamBIS database, with review of their medical histories as pertaining to CRC diagnosis, screening, and surveillance from 1980 to 2015. RESULTS: We identified and reviewed the medical histories of 96 registrants from 62 unique families. Registrants began screening as early as 24 years of age, with the mean age of first screening being at 44.6 ± 10.7 years old. The mean duration of screening was 17.3 ± 10.1 years, and through their screening period, registrants underwent an average of 11.5 ± 9.1 FOBTs and 4.4 ± 3.1 colonoscopies or sigmoidoscopies.Over the course of screening, 41 (42.7%) registrants were found to have at least one neoplasm of any kind (including adenomas, advanced adenomas, and CRC) as their first positive colonoscopic finding. In total, 12 (12.5%) of the registrants were found to have an advanced neoplasm over the course of screening and surveillance, while only 2 patients were found to be diagnosed with CRC. CONCLUSIONS: The prevalence rates for neoplasms, advanced neoplasms, and CRC in our current study were statistically significantly higher compared with those seen in average-risk populations. This supports the importance of more intensive screening for this subpopulation in preventing colorectal cancers, as well as pre-and early-cancerous neoplasms.

Ideal colonoscopic surveillance intervals to reduce incidence of advanced adenoma and colorectal cancer.

BACKGROUND AND AIMS: There is limited information about the interplay between multiple risk factors contributing to the risk of advanced neoplasia. We determined the actual risk for advanced neoplasia in relation to lapsed time between colonoscopies in people enrolled in a structured surveillance program. This risk information can be used to guide the selection of optimal surveillance intervals. METHODS: Patients were recruited into programs at two major tertiary hospitals, with a personal or family history of advanced neoplasia. Five thousand one hundred forty-one patients had an index and one or more surveillance colonoscopies. Fifty-one percent had a family history of colorectal neoplasia while the remainder had a personal history. RESULTS: Patients with an immediately prior colonoscopy result (prior result) of advanced adenoma had a risk for advanced neoplasia 7.1 times greater than those with a normal prior result. Cancer as a prior result did not confer a greater risk than either a hyperplastic polyp or a nonadvanced adenoma. Being female reduced risk, age increased risk. Only a family history of a first-degree relative diagnosed under 55, or definite or suspected hereditary nonpolyposis colorectal cancer (HNPCC) conferred an increased risk over a personal history of advanced neoplasia. CONCLUSIONS: Most family history categories did not confer excess risk above personal history of advanced neoplasia. A prior cancer poses less of a risk than a prior advanced adenoma. Based on our models, a person with an advanced adenoma should be scheduled for colonoscopy at 3 years, corresponding to a 15% risk of advanced neoplasia for a male aged under 56. Guidelines should be updated that uses a 15% risk as a benchmark for calculating surveillance intervals.

Magnetic resonance colonography for colorectal cancer screening in patients with Lynch syndrome gene mutation.

Lynch syndrome gene carriers have a 50-80% risk of colorectal cancer (CRC). Current guidelines recommend yearly colonoscopy, with associated procedure-related risks. Magnetic resonance colonography (MRC) was evaluated as a non-invasive alternative for CRC screening in this high-risk population. Adult Lynch syndrome gene carriers underwent both screening procedures on the same day. MRI radiologists read the scans and rated image quality. Endoscopists performed colonoscopy unaware of MRC findings until after procedure completion. If lesions were detected, their number, size and location were noted. Post-procedure, patients compared discomfort and inconvenience of MRC and colonoscopy on a visual analogue scale. Thirty patients were recruited. 83% of the MRC scans were of adequate to good quality. MRC detected three lesions in three patients (70, 36, 17 mm). All 3 were independently detected on colonoscopy, excised and found to be CRC. MRC failed to detect a 3 mm CRC found on colonoscopy. CRC prevalence was 13%. Colonoscopy detected a further 30 polyps, all <10 mm. Of these, 17 were hyperplastic polyps and 10 normal mucosa. Colonoscopy had a false positive rate of 32% as defined by histology. MRC failed to detect any polyp <10 mm. Mean patient discomfort scores were 20% for MRC and 68% for colonoscopy, P = 0.003. Mean patient inconvenience scores were 54% for MRC and 52% for colonoscopy, P = 0.931. MRC was reliable in detecting large polyps, potentially CRC. However MRC currently has poor sensitivity in detecting small polyps, limiting its utility in adenoma screening at this time. MRC was associated with less discomfort than CC.