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Genetics of Colorectal Cancer (PDQ®)

Health Professional Version
Last Modified: 02/28/2013

Changes to This Summary (02/28/2013)

The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.

Introduction

Updated statistics with estimated new cases and deaths for 2013 (cited American Cancer Society as reference 1).

Added text to state that even in Lynch syndrome (LS), a hereditary form of colon cancer, cigarette smoking has been identified as a risk factor for the development of colorectal adenomas (cited Winkels et al. as reference 66).

Colon Cancer Genes

Revised text to state that a variety of LS-associated mutations in MSH2 and MLH1 have been identified; these include founder mutations in the Ashkenazi Jewish, Finnish, Portuguese, and German American populations (cited Pinheiro et al. and Tomsic et al. as references 31 and 32, respectively).

Added De novo mutation rate as a new subsection.

Major Genetic Syndromes

Added Khan et al. as reference 251.

Added text to state that one study of two families with the same EPCAM deletion found few extracolonic cancers and no endometrial cancers (cited Lynch et al. as reference 275).

Added text about a more efficient screening strategy that has been suggested in which staining for only PMS2 and MSH6 are performed (cited Hall et al. as reference 285), although staining for all four mismatch repair proteins remains the current standard of care.

Added text to state that even in centers that rely exclusively on immunohistochemistry (IHC) testing, there may be a role for subsequent microsatellite instability (MSI) testing in cases where the clinical picture suggests LS, notwithstanding the results of IHC.

The Surgical management in LS subsection was renamed from Risk-reducing surgery in LS.

Added text about a quality-of-life and functional outcome survey of LS patients in which global quality-of-life outcomes were comparable among patients with more extensive and less extensive resections (cited Haanstra et al. as reference 350); this parallels the experience in familial adenomatous polyposis (FAP) patients (cited Church et al., Hassan et al., Aziz et al. as references 351, 352, and 353, respectively).

Added Chromoendoscopy as a new subsection.

Added Small Bowel Imaging as a new subsection.

Psychosocial Issues in Hereditary Colon Cancer Syndromes

This section was renamed from Psychosocial Issues in Hereditary Colon Cancer Syndromes: Lynch Syndrome and FAP.

Revised text to state that from the limited studies published to date, there appears to be interest in the use of assisted reproductive technology (ART) for FAP, LS, and Peutz-Jeghers syndrome (PJS) (cited Dewanwala et al. and van Lier et al. as references 29 and 30, respectively).

Revised Table 15, Summary of Studies Evaluating Attitudes Toward, Interest in, or Intention to Use ART for FAP, LS, and PJS, to include a study in LS patients and a study in PJS patients.

Added Issues With Informed Consent for MSI and IHC Tumor Testing as a new subsection.

This summary is written and maintained by the PDQ Cancer Genetics Editorial Board, which is editorially independent of NCI. The summary reflects an independent review of the literature and does not represent a policy statement of NCI or NIH. More information about summary policies and the role of the PDQ Editorial Boards in maintaining the PDQ summaries can be found on the About This PDQ Summary and PDQ NCI's Comprehensive Cancer Database pages.