<unk>  adenomas are most likely diagnosed much more frequently than<unk>  carcinomas. The female to male ratio for<unk>  adenomas is 8:1, while the ratio is 2:1 for the malignant version.<unk>  cancer tends to occur in older patients. The median age at diagnosis for<unk>  carcinomas is approximately 61 years old. Typically a painless thyroid mass is found in patients with this type of cancer. As expected, patients with carcinoma usually present larger tumors than patients with adenoma. Rarely, the cancer can spread to the lymph nodes. On few occasions, patients with<unk>  carcinoma have distant metastases in the lungs or surrounding bones.<unk>  neoplasms are somewhat difficult to differentiate between being benign or malignant. Since the size and growth pattern of the tumor cannot be used to determine malignancy, although larger tumors have higher incidence of malignancy,<unk>  adenomas and carcinomas have to be separated by the presence, in the case of carcinomas, or absence, in the case of adenomas, of both capsular invasion and vascular invasion. Tumors displaying only capsular invasion tend to behave less aggressively than those with vascular invasion.<unk>  carcinomas are characterized as either minimally invasive or widely invasive tumors. While the minimally invasive or encapsulated carcinoma is fully surrounded by a fibrous capsule, the widely invasive carcinoma shows extensive area of both capsular and vascular invasion with the leftover capsule typically difficult to identify. Classification is important since widely invasive tumors can have outcomes with a 55% mortality rate.
Hürthle cell
Aschoff cell
Langhans giant cell
Nevus cell
Elliptocyte
Nurse cell
Navicular cell
Null cell