Thyroid cancer in two siblings with FAP syndrome and APC mutation

Excerpt

Familial adenomatous polyposis (FAP) is characterized by the presence of numerous polyps that line the mucosa of the large intestine and, in some cases, with other extraintestinal manifestations such as other gastrointestinal adenomas, osteomas and desmoid tumours. In rare cases, duodenal or thyroid carcinomas accompany this syndrome. The thyroid cancer (TC) cases account for 1–2% of FAP patients, and the risk of development of papillary carcinoma in a female polyposis patient is 100–160 times higher than in the background population. So far, there were described only eight FAP families, with more than one family member suffering from TC. Thyroid carcinoma developing in FAP patients tends to share some common characteristics, e.g. early onset, multicentricity, high frequency of papillary histology and favourable prognosis. …