Decentralized colonoscopic surveillance with high patient compliance prevents hereditary and familial colorectal cancer

Self-adherence to post-colonoscopy consults in patients undergoing diagnostic colonoscopy: Findings from a cross-sectional, quantitative survey at a South African quaternary hospital

Post-colonoscopy consults empower patients to make informed decisions around their subsequent treatment, and non-compliance with these consults ("no-shows") hinders disease management. There is a paucity in the literature regarding self-adherence to post-colonoscopy consults in resource-limited settings such as South Africa. An understanding of self-adherence to post-colonoscopy consults in this setting is required to establish whether improved interventions are needed, and what specific elements of self-adherence should be addressed with these interventions. The objective of this hypothesis-generating, cross-sectional, quantitative survey was to conduct a baseline assessment of cognitive, motivational, social, and behavioural variables related to self-adherence to post-colonoscopy consults in patients who underwent diagnostic colonoscopy at a South African quaternary hospital. The Adherence Determinants Questionnaire (ADQ) was administered in 47 patients to establish a baseline assessment of elements related to self-adherence to post-colonoscopy consults, including interpersonal aspects of care, perceived utility, severity, susceptibility, subjective norms, intentions, and supports/barriers. ADQ scores were transformed to a percentage of the maximum score for each element (100.0%). The overall mean transformed ADQ score was 57.8%. The mean transformed scores for specific ADQ components were as follows: subjective norms (40.8%), perceived severity (55.4%), perceived utility (56.6%), intentions (59.4%), supports/barriers (59.9%), interpersonal aspects (62.2%), and perceived susceptibility (65.9%). There were no statistically significant differences in overall mean transformed ADQ scores and individual ADQ elements across categories of participant age (p-values ranging between 0.180 and 0.949 when compared between participants ≤40 years and >40 years old), gender (p-values ranging between 0.071 and 0.946 when compared between males and females), and race (p-values ranging between 0.119 and 0.774 when compared between Black Africans and non-Black Africans). Our findings suggest a general need for appropriate interventions to improve self-adherence to post-colonoscopy consults in our setting.

Uptake and Short-term Outcomes of High-risk Screening Colonoscopy Billing Codes: A Population-based Study Among Young Adults

Background

Persons suspected or confirmed with familial colorectal cancer syndrome are recommended to have biennial colonoscopy from late adolescence or early adulthood. Persons without a syndrome but with one or more affected first-degree relatives are recommended to begin colonoscopy 10 years before the age at diagnosis of the youngest affected relative, and every 5 to 10 years. Ontario introduced colonoscopy billing codes for these two indications in 2011.

Methods

We identified persons in Ontario under 50 years of age, without a prior history of colorectal cancer or inflammatory bowel disease, with one or more of these billing claims between 2013 and 2017. We described the index colonoscopy, and subsequent colonoscopy up-to-date status. We computed average annual rates of colorectal and other cancer diagnoses, and displayed mean cumulative function plots, stratified by billing code, age and sex.

Results

Billing claims for ‘familial syndrome’ high-risk screening colonoscopy were identified among 14,846 persons; the average annual rate of CRC diagnoses was 38.6 per 100,000 among males and 22.2 among females. Colonoscopy up-to-date status fell to 50% within 7 years. Billing claims for ‘first-degree relative’ screening colonoscopy was identified among 49,505 persons; average annual rates of CRC diagnoses were 16.3 among males and 13.5 per 100,000 among females, respectively.

Conclusion

Colorectal cancer was more frequent following billing claims for high-risk screening colonoscopy for familial syndromes, as were noncolorectal malignancies potentially associated with these syndromes. This billing claim for familial colorectal cancer syndrome colonoscopy appears to identify a group at elevated short-term risk for cancer.

Endoscopy to Diagnose and Prevent Digestive Cancers in Lynch Syndrome

Lynch syndrome patients could benefit from various recommendations to prevent digestive cancers. In this review, we summarize the criteria to identify Lynch syndrome in patients with digestive cancers. We detail endoscopic screening procedures in patients with Lynch syndrome for gastric, small bowel, pancreatic, and colorectal cancers. We review the precise modalities of endoscopic follow-up, particularly the discrepancies that exist between the guidelines of the various scientific societies. We discuss the treatment of colorectal cancers in Lynch syndrome cases and patient adherence to endoscopic follow-up programs.

A geographically matched control population efficiently limits the number of candidate disease-causing variants in an unbiased whole-genome analysis

Whole-genome sequencing is a promising approach for human autosomal dominant disease studies. However, the vast number of genetic variants observed by this method constitutes a challenge when trying to identify the causal variants. This is often handled by restricting disease studies to the most damaging variants, e.g. those found in coding regions, and overlooking the remaining genetic variation. Such a biased approach explains in part why the genetic causes of many families with dominantly inherited diseases, in spite of being included in whole-genome sequencing studies, are left unsolved today. Here we explore the use of a geographically matched control population to minimize the number of candidate disease-causing variants without excluding variants based on assumptions on genomic position or functional predictions. To exemplify the benefit of the geographically matched control population we apply a typical disease variant filtering strategy in a family with an autosomal dominant form of colorectal cancer. With the use of the geographically matched control population we end up with 26 candidate variants genome wide. This is in contrast to the tens of thousands of candidates left when only making use of available public variant datasets. The effect of the local control population is dual, it (1) reduces the total number of candidate variants shared between affected individuals, and more importantly (2) increases the rate by which the number of candidate variants are reduced as additional affected family members are included in the filtering strategy. We demonstrate that the application of a geographically matched control population effectively limits the number of candidate disease-causing variants and may provide the means by which variants suitable for functional studies are identified genome wide.

Colonoscopic surveillance - a cost-effective method to prevent hereditary and familial colorectal cancer

OBJECTIVE

Approximately 20-30% of all colorectal cancer (CRC) cases may have a familial contribution. The family history of CRC can be prominent (e.g., hereditary colorectal cancer (HCRC)) or more moderate (e.g., familial colorectal cancer (FCRC)). For family members at risk, colonoscopic surveillance is a well-established method to prevent both HCRC and FCRC, although the evidence for the exact procedures of the surveillance is limited. Surveillance can come at a high price if individuals are frequently examined, as this may result in unnecessary colonoscopies in relation to actual risk for CRC. This study analyses the cost-effectiveness of a surveillance programme implemented in the Northern Sweden Health Care Region.

METHODS

The study includes 259 individuals prospectively recorded in the colonoscopic surveillance programme registry at the Cancer Prevention Clinic, Umeå University Hospital. We performed a cost-utility analysis with a contrafactual design: we compared observed costs and loss of quality-adjusted life years (QALYs) due to CRC with the surveillance programme to an expected outcome without surveillance. The main measure was the incremental cost-effectiveness ratio (ICER) between surveillance and non-surveillance. Scenario analysis was used to explore uncertainty.

RESULTS

The ICER between surveillance and non-surveillance in the base model was 3596€/QALY. The ICER varied from -4620€ in the best-case scenario to 33,779€ in the worst-case scenario.

CONCLUSION

Colonoscopic surveillance is a very cost-effective method to prevent HCRC and FCRC compared to current thresholds for cost-effectiveness and other cancer preventive interventions.