The prevalence of thyroid cancer and benign thyroid disease in patients with familial adenomatous polyposis may be higher than previously recognized

Purpose: Patients with familial adenomatous polyposis (FAP) are at increased risk for colorectal cancer and extracolonic neoplasms. The prevalence of thyroid cancer (TC) and benign thyroid disease in this patient population is unclear, and guidelines for screening for TC in these patients are not well established. The purpose of this study was to report the prevalence of TC and benign thyroid disease in patients with FAP. Methods: The prospectively maintained Hereditary Colorectal Cancer Family Registry at Memorial Sloan-Kettering Cancer Center was queried to identify patients with FAP and with TC and/or benign thyroid disease. Results: Sixty-six patients with FAP were identified. There were 30 men and 36 women, with a median age of 38.6 years. Four (6.1%) patients had a history of TC. All were women, with a mean age at TC diagnosis of 36.5 years. Three of the 4 TCs were papillary thyroid cancer. Two patients with TC presented with palpable nodules. An additional 6 (9.1%) patients with FAP had a history of benign thyroid disease, including nodules (3), hypothyroidism (2), cysts (2), goiter (1), and thyroiditis (1). Three of 4 patients with TC and all 6 patients with benign thyroid disease had other extracolonic manifestations associated with FAP. Conclusions: The prevalences of TC (6.1%) and benign thyroid disease (9.1%) are increased in our patients with FAP and are higher than noted in some previous reports. Periodic thyroid ultrasound screening should be considered in patients with FAP to further elucidate the prevalence and for possible early detection of TC and benign thyroid disease in this population.