Variables affecting penetrance of gastric and duodenal phenotype in familial adenomatous polyposis patients.

BACKGROUND: Patients with familial adenomatous polyposis (FAP) frequently undergo colectomy to reduce the 70 to 90% lifetime risk of colorectal cancer. After risk-reducing colectomy, duodenal cancer and complications from duodenal surgeries are the main cause of morbidity. Our objective was to prospectively describe the duodenal and gastric polyp phenotype in a cohort of 150 FAP patients undergoing pre-screening for a chemoprevention trial and analyze variables that may affect recommendations for surveillance. METHODS: Individuals with a diagnosis of FAP underwent prospective esophagogastroduodenoscopy using a uniform system of mapping of size and number of duodenal polyps for a 10 cm segment. Gastric polyps were recorded as the total number. RESULTS: The distribution of the count and sum diameter of duodenal polyps were statistically different in two genotype groups, those with APC mutations associated with classic FAP had a greater count (median 17) and sum diameter of polyps (median 32 mm) than those with APC mutations associated with attenuated FAP (median count 4 and median sum diameter of 7 mm) (p < 0.0001). The number of gastric polyps did not differ based on genotype (p = 0.67) but advancing age correlated with severity of gastric polyposis (p = 0.019). Spigelman (modified) staging of II or greater was found in 88% of classic FAP patients and 48% attenuated FAP patients. Examples of severe and mild upper GI phenotype are observed in patients with identical APC mutations, showing that the APC mutation location is not absolutely predictive of an upper GI phenotype. CONCLUSIONS: Most FAP patients have duodenal and gastric polyps which become more prevalent and advanced with age. Standard upper endoscopic surveillance is recommended based on personal history independent of APC mutation location. TRIAL REGISTRATION: NCT 01187901 registered August 24, 2010, prospective to enrollment.

Effect of Sulindac and Erlotinib vs Placebo on Duodenal Neoplasia in Familial Adenomatous Polyposis: A Randomized Clinical Trial.

IMPORTANCE: Patients with familial adenomatous polyposis (FAP) are at markedly increased risk for duodenal polyps and cancer. Surgical and endoscopic management of duodenal neoplasia is difficult and chemoprevention has not been successful. OBJECTIVE: To evaluate the effect of a combination of sulindac and erlotinib on duodenal adenoma regression in patients with FAP. DESIGN, SETTING, AND PARTICIPANTS: Double-blind, randomized, placebo-controlled trial, enrolling 92 participants with FAP, conducted from July 2010 through June 2014 at Huntsman Cancer Institute in Salt Lake City, Utah. INTERVENTIONS: Participants with FAP were randomized to sulindac (150 mg) twice daily and erlotinib (75 mg) daily (n = 46) vs placebo (n = 46) for 6 months. MAIN OUTCOMES AND MEASURES: The total number and diameter of polyps in the proximal duodenum were mapped at baseline and 6 months. The primary outcome was change in total polyp burden at 6 months. Polyp burden was calculated as the sum of the diameters of polyps. The secondary outcomes were change in total duodenal polyp count, change in duodenal polyp burden or count stratified by genotype and initial polyp burden, and percentage of change from baseline in duodenal polyp burden. RESULTS: Ninety-two participants (mean age, 41 years [range, 24-55]; women, 56 [61%]) were randomized when the trial was stopped by the external data and safety monitoring board because the second preplanned interim analysis met the prespecified stopping rule for superiority. Grade 1 and 2 adverse events were more common in the sulindac-erlotinib group, with an acne-like rash observed in 87% of participants receiving treatment and 20% of participants receiving placebo (P < .001). Only 2 participants experienced grade 3 adverse events. [table: see text]. CONCLUSIONS AND RELEVANCE: Among participants with FAP, the use of sulindac and erlotinib compared with placebo resulted in a lower duodenal polyp burden after 6 months. Adverse events may limit the use of these medications at the doses used in this study. Further research is necessary to evaluate these preliminary findings in a larger study population with longer follow-up to determine whether the observed effects will result in improved clinical outcomes. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT 01187901.

LocalVar: a local variant collection manager to asynchronously detect synonyms, HGVS expression changes, and variant interpretation changes from ClinVar.

While there are several public repositories of biological sequence variation data and associated annotations, there is little open-source tooling designed specifically for the upkeep of local collections of variant data. Many clinics curate and maintain such local collections and are burdened by frequent changes in the representation of those variants and evolving interpretations of clinical significance. A dictionary of genetic variants from the Huntsman Cancer Institute was analyzed over a period of two years and used to inform the development of LocalVar. This tool uses publicly available ClinVar files to provide the following functionality: auto-complete search bar to pre-empt duplicate entries; single or bulk new variant record entry; auto-detection of duplicate and synonymous variant records; asynchronous suggestion of HGVS expression or variant interpretation updates; extensive edit history tracking; and the easy export of the collection (.csv), edit history (.json), or HGVS synonym bins (.json).

Active BRAF-V600E is the key player in generation of a sessile serrated polyp-specific DNA methylation profile.

BACKGROUND: Sessile serrated polyps (SSPs) have emerged as important precursors for a large number of sporadic colorectal cancers. They are difficult to detect during colonoscopy due to their flat shape and the excessive amounts of secreted mucin that cover the polyps. The underlying genetic and epigenetic basis for the emergence of SSPs is largely unknown with existing genetic studies confined to a limited number of oncogenes and tumor suppressors. A full characterization of the genetic and epigenetic landscape of SSPs would provide insight into their origin and potentially offer new biomarkers useful for detection of SSPs in stool samples. METHODS: We used a combination of genome-wide mutation detection, exome sequencing and DNA methylation profiling (via methyl-array and whole-genome bisulfite sequencing) to analyze multiple samples of sessile serrated polyps and compared these to familial adenomatous polyps. RESULTS: Our analysis revealed BRAF-V600E as the sole recurring somatic mutation in SSPs with no additional major genetic mutations detected. The occurrence of BRAF-V600E was coincident with a unique DNA methylation pattern revealing a set of DNA methylation markers showing significant (~3 to 30 fold) increase in their methylation levels, exclusively in SSP samples. These methylation patterns effectively distinguished sessile serrated polys from adenomatous polyps and did so more effectively than parallel gene expression profiles. CONCLUSIONS: This study provides an important example of a single oncogenic mutation leading to reproducible global DNA methylation changes. These methylated markers are specific to SSPs and could be of important clinical relevance for the early diagnosis of SSPs using non-invasive approaches such as fecal DNA testing.

Association of Sulindac and Erlotinib vs Placebo With Colorectal Neoplasia in Familial Adenomatous Polyposis: Secondary Analysis of a Randomized Clinical Trial.

Importance: Patients with familial adenomatous polyposis (FAP) are at markedly increased risk for colorectal polyps and cancer. A combination of sulindac and erlotinib led to a 71% reduction in duodenal polyp burden in a phase 2 trial. Objective: To evaluate effect of sulindac and erlotinib on colorectal adenoma regression in patients with FAP. Design, Setting, and Participants: Prespecified secondary analysis for colorectal adenoma regression was carried out using data from a double-blind, randomized, placebo-controlled trial, enrolling 92 patients with FAP, conducted from July 2010 to June 2014 in Salt Lake City, Utah. Interventions: Patients were randomized to sulindac, 150 mg twice daily, and erlotinib, 75 mg daily (n = 46), vs placebo (n = 46) for 6 months. Main Outcomes and Measurements: The total number of polyps in the intact colorectum, ileal pouch anal anastomosis, or ileo-rectum were recorded at baseline and 6 months. The primary outcomes were change in total colorectal polyp count and percentage change in colorectal polyps, following 6 months of treatment. Results: Eighty-two randomized patients (mean [SD] age, 40 [13] years; 49 [60%] women) had colorectal polyp count data available for this secondary analysis: 22 with intact colon, 44 with ileal pouch anal anastomosis and 16 with ileo-rectal anastomosis; 41 patients received sulindac/erlotinib and 41 placebo. The total colorectal polyp count was significantly different between the placebo and sulindac-erlotinib group at 6 months in patients with net percentage change of 69.4% in those with an intact colorectum compared with placebo (95% CI, 28.8%-109.2%; P = .009). Conclusion and Relevance: In this double-blind, placebo-controlled, randomized trial we showed that combination treatment with sulindac and erlotinib compared with placebo resulted in significantly lower colorectal polyp burden after 6 months of treatment. There was a reduction in polyp burden in both those with an entire colorectum and those with only a rectal pouch or rectum. Trial Registration: clinicaltrials.gov Identifier: NCT01187901.