Follicular thyroid carcinoma is a type of cancer that originates in the follicular cells of the thyroid gland. These cells are responsible for producing hormones that regulate metabolism. This cancer is generally considered less aggressive than papillary thyroid carcinoma, but it can still spread to other parts of the body, particularly the lungs and bones. Diagnosis typically involves a combination of imaging tests, such as ultrasound, and a biopsy to confirm the presence of cancerous cells. Treatment often includes surgery to remove the affected part of the thyroid, and in some cases, radioactive iodine therapy may be used to eliminate remaining cancer cells.