An alternative approach to establishing unbiased colorectal cancer risk estimation in Lynch syndrome.

Purpose: Biallelic pathogenic variants in the mismatch repair (MMR) genes cause a recessive childhood cancer predisposition syndrome known as constitutional mismatch repair deficiency (CMMRD). Family members with a heterozygous MMR variant have Lynch syndrome. We aimed at estimating cancer risk in these heterozygous carriers as a novel approach to avoid complicated statistical methods to correct for ascertainment bias.

Gastrointestinal Polyposis in Cowden Syndrome.

Goals: To further characterize the gastrointestinal manifestations of Cowden syndrome in clinically well-annotated patients to improve the diagnosis of this syndrome.

Background: The gastrointestinal manifestations of Cowden Syndrome, an important heritable and multiorgan cancer syndrome, are not well defined. Proper diagnosis is essential for effective cancer surveillance and prevention in these patients.

Morphologic characterization of hamartomatous gastrointestinal polyps in Cowden syndrome, Peutz-Jeghers syndrome, and juvenile polyposis syndrome.

The morphologic features of the gastrointestinal polyps in hamartomatous polyposis syndromes are poorly defined. Our aim was to better characterize the gastrointestinal hamartomas in these syndromes. A blinded review was performed regarding many histologic features for every polyp.

Serrated polyposis: colonic phenotype, extracolonic features, and familial risk in a large cohort.

Background: Serrated polyposis is a poorly understood and likely underdiagnosed condition. Little is known regarding the colorectal cancer risk, extracolonic phenotype, and cause of serrated polyposis.

Objective: The aim of this study is to describe the clinical and family history features of a large cohort of individuals with serrated polyposis.

Role of rapid sequence whole-body MRI screening in SDH-associated hereditary paraganglioma families.

Patients with germline mutations in one of the SDH genes are at substantially increased risk of developing paragangliomas, pheochromocytomas (pheos), and other tumors (all combined referred to as SDH-related tumors). However, limited data exist on screening in SDH mutation carriers and no studies have evaluated whole-body MRI as a screening tool in asymptomatic patients. This was a single-center observational study.

Genetic testing by cancer site: colon (polyposis syndromes).

Hereditary colonic polyposis conditions are all characterized by high rates of cancer, but they have diverse phenotypes, genetic heterogeneity, and assorted inheritance patterns. The most well known of these conditions include familial adenomatous polyposis, attenuated familial adenomatous polyposis, MUTYH (MutY human homolog)-associated polyposis, Peutz-Jeghers syndrome, juvenile polyposis syndrome, and Cowden syndrome. Early recognition of these conditions is not only vital for management in affected individuals, but also for prevention and early detection in at-risk relatives.

Hereditary and familial colon cancer.

Between 2% to 5% of all colon cancers arise in the setting of well-defined inherited syndromes, including Lynch syndrome, familial adenomatous polyposis, MUTYH-associated polyposis, and certain hamartomatous polyposis conditions. Each is associated with a high risk of colon cancer. In addition to the syndromes, up to one-third of colon cancers exhibit increased familial risk, likely related to inheritance.

Evaluating Lynch syndrome in very early onset colorectal cancer probands without apparent polyposis.

To characterize the frequency of germline mutations associated with Lynch syndrome and review the potential expanded differential diagnoses in very early onset colorectal cancer (CRC) cases without apparent polyposis. Retrospectively reviewed medical records of 96 probands with CRC diagnosed prior to age 36 from three cancer centers. Determined the frequency of germline mutations in probands meeting different clinical criteria used to identify Lynch syndrome.

Working through a diagnostic challenge: colonic polyposis, Amsterdam criteria, and a mismatch repair mutation.

The two most common causes of hereditary colorectal cancer are Lynch syndrome and familial adenomatous polyposis (FAP). The phenotype of Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC), is differentiated in part from FAP by the lack of profuse colonic polyposis. Here we describe a proband who presented with greater than 50 adenomatous colonic polyps prior to developing cancer of the colon and urinary bladder, and a family history that fulfills the Amsterdam criteria.

Assessing the predictive accuracy of hMLH1 and hMSH2 mutation probability models.

Hereditary nonpolyposis colorectal cancer (HNPCC) is characterized by a susceptibility to colorectal and extra-colonic cancers. Several guidelines exist for the identification of families suspected of having HNPCC, however these guidelines lack adequate sensitivity and specificity. In an attempt to improve accuracy for the detection of individuals with HNPCC, the Wijnen pre-test probability model (1998) and Myriad Genetics Laboratory prevalence table (2004) were developed.