Anaplastic tumors are rare sorts that usually appear in people over 60 years
of age and are believed to develop from a primary (existing first)
follicular or papillary cancer. They are the fastest growing of the thyroid
tumors and quickly invade the neck area and metastasize to other sites and
causing a high number of fatalities. In contrast to the others, when viewed
beneath the microscope, anaplastic cancer cells have very little resemblance to
normal thyroid tissue and are therefore referred to as undifferentiated.
Medullary Thyroid Cancer (MTC)
This is the only form of thyroid cancer to develop in the non-hormone
producing C cells. These tumors often produce carcinoembryonic antigen (CEA),
which a hormone produced by some cancers that can be found by taking a blood
test. Although these tumors are slow-growing in terms of invading the nearby
tissues and organs, they metastasize quickly and are often found to have
traveled to the lung, liver or lymph nodes by the time of the initial
diagnosis.
There are two different types of MTC. One is called isolated familial
medullary cancer (FTMC) and inherited through the family genetics. The other
one, sporadic MTC, makes up most of the MTC cases, occurs in only one
lobe, and is not hereditary.
Symptoms
The most common sign of thyroid cancer is the nodule appearing in the neck.
Some health care professionals suggest checking your neck at least twice a year
for abnormal growths.
Sometimes there is pain in the thyroid area of the neck, or traveling up the
neck to the ear area. That may be accompanied by difficulty breathing or
swallowing, swollen lymph nodes, hoarseness, or a cough unaccompanied by a
cold.
Any of those symptoms could also be associated with other non-cancerous
health conditions, but a trip to the doctor should be scheduled for a
professional assessment of the situation.