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1130-0108/2009/101/2/125-132 REVISTA ESPAÑOLA DE ENFERMEDADES DIGESTIVAS Copyright © 2009 ARÁN EDICIONES, S. L.

Recognition and management of hereditary colorectal cancer syndromes
M. Herráiz1,2 and M. Muñoz-Navas1
1

POINT OF VIEW

REV ESP ENFERM DIG (Madrid) Vol. 101. N.° 2, pp. 125-132, 2009

Service of Digestive Diseases and 2Unit of Prevention and High-risk Gastrointestinal CancerClinic. Clínica Universidad de Navarra. Pamplona, Spain

ABSTRACT
Over 1.900 colorectal tumors will arise in association with a hereditary colorectal cancer syndrome in Spain in 2009. The genetic defects responsible for the most common syndromes have been discovered in recent years. Genetic testing helps diagnose affected individuals and allows identification of individuals at-risk.Colonoscopy and prophylactic colectomy decrease colorectal cancer incidence and overall mortality in patients with hereditary colon cancer. Extracolonic tumors are frequent in these syndromes, so specific surveillance strategies should be offered. Key words: Familial adenomatous polyposis. Lynch syndrome. MYH-associated polyposis. Hereditary colon cancer.

Herráiz M, Muñoz-Navas M. Recognition andmanagement of hereditary colorectal cancer syndromes. Rev Esp Enferm Dig 2009; 101: 125-132.

In 2009, it is estimated that around 38,000 people (1) in Spain will be diagnosed with colorectal cancer (CRC). Among these cases, more than 15% will exhibit familial

INTRODUCTION

clustering, and over 1,900 tumors (5%) will arise in association with a hereditary colorectal cancer syndrome. The mostcommon hereditary colon cancer syndromes are: Familial Adenomatous Polyposis (FAP), attenuated FAP (AFAP), MYH associated polyposis (MAP), and Lynch syndrome, also known as Hereditary Non-Polyposis Colorectal Cancer syndrome (HNPCC) (2). During the last two decades, the most important advancement has been the identification of the genes that underlie these syndromes. This has permitted more accurateclassifications of the various syndromes based upon genetic criteria, and consequently this has resulted in more tailored management strategies based on these criteria (3). The management of individuals with hereditary colon cancer or at-risk for hereditary colon cancer is dramatically different, so recognizing these syndromes is critical. Specifically, surveillance strategies for colon andextra-colonic tumors as well as surgical approaches (4) for the prevention and treatment of cancer reflect the heightened risks. This review is focused on current treatment strategies in hereditary colon cancer. It is important to recognize that “treatment” includes not only management of already diagnosed cancers but also to prevention of cancer in these high-risk populations. We first briefly summarizethe major clinical features of each syndrome, including pattern of inheritance and penetrance, age at diagnosis and associated extra-colonic tumors. Familial adenomatous polyposis and attenuated FAP

Correspondence: Maite Herráiz. Servicio de Aparato Digestivo. Unidad de Prevención y Consulta de Alto Riesgo de Tumores Digestivos. Clínica Universidad de Navarra. Avda. Pio XII, 36. 31008 Pamplona,Spain. e-mail: mherraizb@unav.es

Received: 04-02-09. Accepted: 04-02-09.

FAP is the most common adenomatous polyposis syndrome. Its prevalence is 1:5.000-10.000, with a uniform worldwide distribution, affecting both genders equally (5). Inherited in an autosomal dominant manner with a virtually penetrance of 100%, it is caused by a germline mutation in the Adenomatous Polyposis Coli (APC)tu-

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REV ESP ENFERM DIG (Madrid)

mor suppressor gene on chromosome 5q21 (6). In 1520%, the cases are “de novo” without clinical or genetic evidence of FAP in the parents (7). Recent studies indicate the presence of mosaicism in approximately 15% of such cases (8,9). Classic FAP is characterized by the development of hundreds to thousands of colorectal...