There are several types of thyroid cancer including: Papillary, which is the most common form of thyroid cancer; Follicular, which is most common in adults over 50 years of age; medullary, which occurs in roughly 3% to 4% of all cases. There are also several other rare forms, including anaplastic and thyroid lymphoma.
Thyroid cancer is staged by type since the affected cells tend to act differently.
Papillary and Follicular
Stage I. Any size mass on the thyroid. May involve tissues around the thyroid and lymph nodes close to the thyroid. No spread of cancer past the thyroid area.
Stage II. Any size mass that involves the thyroid but is also found outside the thyroid area. It also involves lymph nodes and may be found in the lungs and/or bone.
Stage III. Mass larger than 4 centimeters in the thyroid and cancer cells are found outside the thyroid. It may also be found in the lymph nodes near the voice box.
Stage IV. Cancer is found in the trachea, voice box, lymph nodes, and esophagus. Stage IVB it is found in the spinal column and blood vessels that supply the lungs. It may or may not be found in the lymph nodes. In Stage IVC it is found in the lungs, bones, and lymph nodes.
Stage 0. No tumor on the thyroid, but positive blood test.
Stage I. Nodule that is 2 centimeters or smaller.
Stage II. Nodule that is 2 centimeters or larger on the thyroid gland. May be in tissues around the thyroid but is not found in the lymph nodes.
Stage III. Any size mass found in lymph nodes around the voice box and trachea and possibly in tissues around the thyroid.
Stage IV. Any size mass found outside the thyroid, in the trachea, voice box, and esophagus. Cancer is also found in nearby lymph nodes. Stage IVB it is found in the spinal column, blood vessels that supply the lungs, and lymph nodes. Stage IVC cancer is found in lymph nodes, bones, and lungs.
This cancer spreads very quickly and is classified as:
Stage IVA. Found in the actual thyroid gland and lymph nodes.
Stage IVB. Spread outside the thyroid gland and lymph nodes.
Stage IVC. Spread throughout the body, lymph nodes, lungs, and bones.