paywalled: Risk of Colonic Neoplasia After Proctectomy for Rectal Cancer in Hereditary Nonpolyposis Colorectal Cancer (Lynch Syndrome)

abstract

Abstract

Objective: To define the neoplastic risk in the remaining colon after proctectomy for rectal cancer in patients with hereditary nonpolyposis colorectal cancer (HNPCC). (Lynch Syndrome)

Conclusions: Surgeons and patients need to be aware of substantial risk for metachronous neoplasia after proctectomy. Selection of operation should be individualized, but total proctocolectomy and ileoanal pouch should be strongly considered. If patients undergo proctectomy alone, close surveillance is mandatory.

March 6, 2012 - Screening for Colorectal Cancer: A Guidance Statement From the American College of Physicians (pdf) including high risk

Blogger's Note: if searching for Lynch Syndrome, the older term 'HNPCC' will need to be used


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"Genetic or clinical diagnosis of hereditary nonpolyposis colorectal cancer (HNPCC): colonoscopy every one to two years beginning at age 20 to 25 years or 10 years before the age of the youngest case in the immediate family."

Gynecological Health - Ovarian Cancer and Hereditary Nonpolyposis Colon Cancer (HNPCC) - Lynch Syndrome - | Johns Hopkins Medicine Health Library (basic info)

abstract: Revised Bethesda Guidelines: compliance in identifying HNPCC affected families (Lynch Syndrome)

Conclusion
Based on these results, there is a marked incompliance with revised Bethesda guidelines when assessing patients with colorectal cancer. This has a significant impact on clinical pathways for the management of HNPCC  (Lynch Syndrome) families.

News - Penn State Biochemistry and Molecular Biology Colorectal Cancer month/Lynch Syndrome excerpt

"Lynch syndrome, previously referred to as hereditary non-polyposis colorectal cancer or HNPCC, represents the most common hereditary cause of colorectal cancer.
Approximately 1 in 400 to 1 in 500 individuals in the general population are estimated to have Lynch syndrome.

Knowledge, as they say, in this condition, is power. Not only should individuals with Lynch syndrome start their colonoscopies earlier (at 20-25 years of age) and have them more frequently (every 1-2 years), they should also be screened for stomach and small intestine cancer, urinary tract cancers involving the kidneys and ureters, and the hepatobiliary tract, including the gallbladder, bile duct, pancreas and liver.

Further, women with Lynch syndrome should be aware of the increased risk for both endometrial and ovarian cancer and offered the option of prophylactic surgery following childbearing."

abstract: A systematic review of gynecological cancer surveillance in women belonging to Hereditary Nonpolyposis Colorectal Cancer (Lynch syndrome) fa

Conclusions.
Currently available published studies on gynecological cancer surveillance in women with HNPCC do not adequately allow for evidence-based clinical decisions. Detection of endometrial cancer or hyperplasia in nonsymptomatic women belonging to a HNPCC family is improved by adding routine endometrial sampling along with transvaginal ultrasound for surveillance visits. No benefit was shown for ovarian cancer surveillance.

Hereditary Colorectal Cancer: eMedicine Gastroenterology

Background

Hereditary nonpolyposis colorectal cancer (HNPCC), an autosomal-dominant syndrome, accounts for 2-5% of all colorectal carcinomas. Colorectal cancer in patients with hereditary nonpolyposis colorectal cancer (HNPCC) presents at an earlier age than in the general population and is characterized by an increased risk of other cancers, such as endometrial cancer and, to a lesser extent, cancers of the ovary, stomach, small intestine, hepatobiliary tract, pancreas, upper urinary tract, prostrate, brain, and skin.



Table 1. Seven different genes are known to be associated with HNPCC, 
and all of them are involved with DNA mismatch repair, identified with
the frequencies below.

Mismatch Excision Repaired MMR	Chromosome Location	Frequency of HNPCC Cases
MSH2	2p16	45-50%
MLH1	3p22.3/A>	20%
MSH6	2p16	10%
PMS2	7p22.1	1%
PMS1	2q32.2	Rare
MSH3	5q14.1	Rare
EXO1	1q43	Rare
Other genes not yet discovered Table 2. Incidence of different types of cancers between individuals with Lynch syndrome and those in the general population. Table Type of Cancer General Population Risk (by age 70 y) Lynch Syndrome Risk (by age 70 y)   Endometrial 1.5% 40-50% Ovarian 1% 9-12% Upper Urinary Tract Less than 1% 4-10% Stomach Less than 1% 13% (higher in Asians) Small Bowel Less than 1% 1-3% Brain Less than 1% 1-4% Biliary Tract Less than 1% 1-5%		20-25%

abstract: Genetic profiles distinguish different types of hereditary ovarian cancer

"The results indicate that HBOC and HNPCC (Lynch Syndrome) associated ovarian cancer develop along distinct genetic pathways and genetic profiles can thus be applied to distinguish between different types of hereditary ovarian cancer."

abstract: Risk of colorectal and endometrial cancers in EPCAM deletion-positive Lynch syndrome: a cohort study : The Lancet Oncology (multi-national study)

Note: (abstract) study includes 194 mutation carriers with references to pancreatic and duodenal cancers; more information on EPCAM genetics can be found by searching this blog

Duodenal cancer - Wikipedia Duodenal cancer is a cancer in the beginning section of the small intestine. It is relatively rare compared to gastric cancer and colorectal cancer. en.wikipedia.org/wiki/Duodenal_cancer

full free access: 2009 Lynch syndrome (hereditary non-polyposis colorectal cancer) and endometrial carcinoma -- Journal of Clinical Pathology (note reference to clear cell ovarian cancer)

Abstract

Women with hereditary non-polyposis colorectal cancer (HNPCC)/Lynch syndrome have a high risk for endometrial cancer (EC) and frequently present with a gynaecological cancer as their first or sentinel malignancy. Identification of these patients is important given their personal and family risk for synchronous and metachronous tumours. Modalities to detect ECs for the possibility of HNPCC include microsatellite instability assay, immunohistochemistry for DNA mismatch repair proteins, MLH1 promoter hypermethylation assay and mutational analysis of DNA mismatch repair genes. The revised Bethesda guidelines provide screening criteria for HNPCC in colorectal cancers (CRCs). However, there are currently no such screening recommendations for women with endometrial carcinoma. While age and family history are useful screening criteria, their sensitivity has been shown to be low for detection of HNPCC in EC. Expansion of these criteria to include tumour morphology (presence of tumour infiltrating lymphocytes and tumour heterogeneity including dedifferentiated/undifferentiated ECs) and topography (lower uterine segment localisation) as well as presence of synchronous ovarian clear cell carcinomas may significantly enhance the detection of patients with EC at risk for HNPCC. Consideration should be given to incorporating these screening criteria into a revision of the Bethesda guidelines for detecting EC patients at highest risk for HNPCC.

Genetic profiles distinguish different types of hereditary ovarian cancer

Abstract:

Heredity represents the strongest risk factor for ovarian cancer with disease predisposing mutations identified in 15% of the tumors. With the aim to identify genetic classifiers for hereditary ovarian cancer, we profiled hereditary ovarian cancers linked to the hereditary breast and ovarian cancer (HBOC) syndrome and the hereditary non-polyposis colorectal cancer (HNPCC) (Lynch Syndrome) syndrome. Genome-wide array comparative genomic hybridization was applied to 12 HBOC associated tumors with BRCA1 mutations and 8 HNPCC associated tumors with mismatch repair gene mutations with 24 sporadic ovarian cancers as a control group. Unsupervised cluster analysis identified two distinct subgroups related to genetic complexity. Sporadic and HBOC associated tumors had complex genetic profiles with an average 41% of the genome altered, whereas the mismatch repair defective tumors had stable genetic profiles, with an average 18% of the genome altered. Losses of 4q34, 13q12-q32 and 19p13 were overrepresented in the HBOC subset. Discriminating genes within these regions include BRCA2, FOXO1A and RB1. Gains on chromosomes 17 and 19 characterized the HNPCC tumors, but target genes herein are unknown.

The results indicate that HBOC and HNPCC associated ovarian cancer develop along distinct genetic pathways and genetic profiles can thus be applied to distinguish between different types of hereditary ovarian cancer.

Gastroenterology and Endoscopy News - Inherited Colon and Rectal Cancer

"In Part 1 of this four-part series, we examine the clinical pathology and molecular biology of (Lynch Syndrome) hereditary nonpolyposis colorectal cancer (HNPCC). In Part 2, we will discuss screening and treatment, and the roles of the epidemiologist, the diagnostician and the surgeon."

An estimated 150,000 Americans may be carriers of the (Lynch Syndrome) HNPCC mutation(s) and have a 90% lifetime risk for developing some type of cancer. (MSH2/MSH6/MLH1/PMS2)

open access: Cancer risk in MLH1, MSH2 and MSH6 mutation carriers; different risk profiles may influence clinical management

Subjects carrying a mutation in one of the MMR genes have a higher risk for developing colorectal cancer, but also for endometrial carcinoma and malignancies of the stomach, small bowel, ovaries, upper uroepithelial tract, biliary tract, skin and brain.(pancreas)