The role of mutation analysis of the APC gene in the management of FAP patients. A controversial issue.

BACKGROUND: A correlation between the location of mutation in the adenomatous polyposis coli (APC) gene and clinical manifestations of familial adenomatous polyposis (FAP) has repeatedly been reported. Some Authors suggest the use of mutational analysis as a guide to select the best surgical option in FAP patients. However, data coming from studies on large series have raised questions on this issue. The aim of this study is to discuss the role of the genetic tests in the management of FAP.

METHODS: A literature review was performed considering only peer-reviewed articles published between 1991-2015. All the studies examined the role of genetic as a guide for surgical management of FAP.

RESULTS: Of 363 articles identified, 21 were selected for full-text review. We found different positions with regard the use of genetic tests to determine surgical management of FAP. In particular, while consistent correlations between the APC mutation site and FAP phenotype were observed in large series, 8 studies reported a wide variation of genotypephenotype correlation in patients with the same mutation and they recommended that decisions regarding surgical strategy should be based not only on genotype but also on the clinical factors and the will of the patient who must be fully informed.

CONCLUSIONS: The decision on the type and the timing of surgery should be based on the assessment of many factors and genotype assessment should be used in combination with clinical data.

KEY WORDS: Disease severity, Familial adenomatous polyposis, Genetic tests, Genotype-phenotype correlations, Surgical management.