Thyroid Cancer
Staging & Prognosis of Thyroid Cancer
The most common thyroid cancer symptoms are either a thyroid nodule or a lump in the neck. This is usually investigated with an ultrasound scan and needle biopsy to identify thyroid cancer cases.
For the common types, the prognosis of thyroid cancer and the thyroid cancer survival rate is excellent. Usually treatment with thyroid surgery (total thyroidectomy or thyroid lobectomy), radioactive iodine therapy, and thyroid hormone replacement is required.
In people younger than 55 years, differentiated thyroid carcinoma, which includes papillary carcinoma and follicular carcinoma, has an excellent survival rate and are divided into only 2 thyroid cancer stages:
- Stage I if the cancer has not spread to distant parts of the body
- Stage II if the cancer has spread to distant parts of the body (distant metastases)
Thyroid Cancer Survival Statistics
Young patients with stage I cancers can expect thyroid cancer survival rates in the region of 90 to 95% but these figures are lower in patients with stage II differentiated thyroid carcinoma where repeated radioactive iodine treatments may be required.
Staging is more complex for people who are 55 years old or older. Your doctor may describe your thyroid cancer using the TNM (8th Edition) staging system.
T describes the size of the tumour. There are four main stages ranging from T1 – T4.
N describes whether the cancer cells have spread to the lymph nodes close to the thyroid gland. There are two stages: in N0 there is no sign of cancer in the lymph glands; in N1 there are cancer cells in the lymph glands.
M describes whether the cancer has spread to another part of the body, such as the lungs or the bones (secondary or metastatic cancer).
There are two stages: M0 is where there are no distant metastases; M1 is where there are distant metastases.
For papillary thyroid carcinoma and follicular thyroid carcinoma the prognosis is most favourable for those under the age of 55 years. Female patients have a slightly better cure rate than male patients, and the long-term cure rates are between 85-95% depending on size of tumour and presence of any neck node spread (see above). The extent of spread of thyroid cancer cells is usually confirmed after thyroid cancer surgery.
In young thyroid cancer patients, even those with spread of their tumour to other organs have a high cure rate. Older patients have a slightly worse outcome from these types of thyroid cancer, but all are potentially associated with long term survival and cure.
For all patients with a thyroid cancer diagnosis where surgery has been undertaken there may be a requirement for thyroid hormone medication long-term monitoring of thyroid hormone levels.
For medullary thyroid cancer, early diagnosis and complete surgical removal of the tumour is imperative for long term cure. However even patients with this cancer type with advanced disease or those not suitable for surgery can have their disease controlled for many years, and the tumour is for the vast majority of patients an indolent disease. Thyroid cancer surgery and radiation therapy are frequently required.
New targeted treatments with oral medications called tyrosine kinase inhibitors are now frequently used for patients with medullary thyroid carcinoma with distant metastases.
Anaplastic cancers have the worst outcome of all the different types of thyroid tumours. Cancer treatment with radiation therapy can slow the growth of these tumours, but very few patients achieve a long-term cure. Recent advances in the understanding of anaplastic thyroid carcinoma and its genetic make-up have allowed new treatments in those have mutations in the BRAF gene.
