Which type of thyroid cancer is known to spread hematogenously?

Follicular thyroid carcinoma is known for its tendency to spread hematogenously, which means it can metastasize through the bloodstream to distant sites in the body. This characteristic is due to the vascularity of this type of cancer; it derives from follicular cells, which are responsible for producing thyroid hormones and are more likely to invade blood vessels compared to other types of thyroid cancer.

In contrast to follicular thyroid carcinoma, papillary thyroid carcinoma typically spreads through lymphatic channels and is less associated with hematogenous spread. While medullary thyroid carcinoma can also metastasize, it primarily spreads to local lymph nodes and possibly through the bloodstream but is not as well-known for hematogenous spread as follicular thyroid carcinoma. Anaplastic thyroid carcinoma is aggressive and may spread rapidly, but it is less common overall and does not primarily spread in a hematogenous manner compared to follicular carcinoma.

Thus, the hallmark of follicular thyroid carcinoma is its propensity for hematogenous metastasis, making it the correct answer in this context.