Genetic Counseling and Testing for Colorectal Cancer in Young Adults: Mini-Review

Volume 1 - Issue 2

Ethem Unal*, Sema Yuksekdag, Abdullah Yildiz, Ozgul Duzgun, Ahmet Topcu, M Taha Demirpolat, Omer Faruk Ozkan

Received: March 12, 2018;   Published: March 15, 2018

DOI: 10.32474/PRJFGS.2018.01.000109

Full Text PDF

To view the Full Article   Peer-reviewed Article PDF

Abstract

Colorectal cancer (CRC) has one of the largest proportions of familial cases. Two to 5% of all colon cancers arise in the setting of inherited syndromes, including Lynch syndrome (hereditary nonpolyposis colorectal cancer [HNPCC]), familial adenomatous polyposis (FAP), attenuated FAP, MUTYH-associated polyposis (MAP), and certain hamartomatous polyposis conditions like Peutz-Jeghers syndrome (PJS) and juvenile polyposis syndrome (JPS). All of these conditions are inherited, autosomal dominant disorders, except MAP, which is autosomal recessive [1]. Although clinical similarities do exist, each has different cancer risks, characteristic clinical features, and separate genetical etiologies. In addition to these syndromes, up to 30 % of colon cancers exhibit increased familial risk, likely related to inheritance. A number of less penetrant, but possibly more frequent susceptibility genes have been identified for this level of inheritance. Determination of predisposing genes allows for accurate risk assessment and more precise screening approaches. Examples include common polymorphisms in genes that regulate metabolism or genes that are regulated by environmental or other genetic factors.

Abbreviations: CRC: Colorectal cancer; HNPCC: Nonpolyposis Colorectal Cancer; FAP: Familial Adenomatous Polyposis; MAP: MUTYHAssociated Polyposis; JPS: Juvenile Polyposis Syndrome.

Abstract| Introduction| Conclusion| References|