A Case of Thyroid Papillary Cancer Associated with Familial Adenomatous Polyposis / 대한내분비학회지

ABSTRACT

Familial adenomatous polyposis (FAP) is an autosomal dominant syndrome, typically characterized by multiple colorectal adenomas and increased incidence of colorectal carcinomas if left untreated. It is caused by germline mutations of the adenomatous polyposis coli (APC) gene, which has been mapped on chromosome 5q21, and is accompanied by various benign and malignant extracolonic manifestations. The prevalence of thyroid tumors developing in patients with FAP is about 1~2%, are associated with FAP and have certain characteristics; mean age of tumor diagnosis at less than 30 years of age, the pathology is the papillary histiotype in more than 90% of cases, including a so-called cribriform- morular pattern, and multifocality is a frequent feature. In a genetic analysis, thyroid cancer in FAP usually has a mutation in the 5-portion of exon 15 between 778 and 1309, on chromosome 5q21. Also, the ret/PTC (especially ret/PTC1 and ret/PTC3) and p53 genes are thought probably to be associated with thyroid cancer in FAP patients. A case of familial adenomatous polyposis, accompanied by thyroid papillary cancer, was experienced in a 29 year-old female. She had hundreds of adenomas throughout the entire colon and congenital hypertrophy of the retinal pigment epithelium (CHRPE). The pathological finding of thyroid cancer was revealed as a mixture of cribriform, trabecular and papillary patterns. In a genetic analysis, she and her brother had a germline mutation of the APC gene at codon 1309. In Korea, there has been no previous case of cribriform-morular pattern and familial genetic analysis in FAP associated with thyroid cancer. Therefore, this case is reported, with a review of the literature