Which of the following statements about follicular carcinoma is/are true?

A. It presents at a later age than papillary carcinoma.

B. It disseminates via hematogenous routes.

D. Extensive angioinvasion portends a poor prognosis.

DISCUSSION: Follicular carcinoma is more common in older patients (peak incidence in the fifth decade). The tumor has a marked propensity for vascular invasion and spreads hematogenously to bone, lung, liver, and central nervous system sites. Local nodal metastases are less common than in papillary carcinoma. Extensive angioinvasion indicates a less favorable prognosis. Papillary carcinoma is the most common type of well-differentiated thyroid carcinomas. Follicular carcinomas are rarely multicentric.