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The type of treatment your doctor will recommend depends on
the type and stage of the cancer and on your overall health. This
section summarizes options usually considered for each type and stage
of thyroid cancer.
Papillary carcinoma and papillary carcinoma
variants
Stage I: Lobectomy
(removal of only the affected side of the thyroid gland) And
Thyroidectomy are the two types of surgery to treat these cancers. Of
the two, total thyroidectomy is most commonly performed. Radioiodine
treatment is sometimes used after thyroidectomy, but the cure rate with
surgery alone is excellent. In the unlikely event of recurrence,
radioiodine treatment can still be offered.
If radioactive iodine treatment is planned, the start of
thyroid hormone therapy may be delayed until the treatment is finished
(usually about 6 weeks after surgery).
Some doctors recommend central compartment neck dissection
(surgical removal of lymph nodes next to the thyroid). Although this
operation has not been shown to improve cancer survival, it lowers the
risk of cancer coming back in the neck area (local recurrence). It also
makes it easier to accurately stage the cancer.
Stages II to IV:
Most patients have a near-total thyroidectomy or total
thyroidectomy with removal and microscopic examination of nearby lymph
nodes. Some doctors recommend central compartment neck dissection
(surgical removal of lymph nodes next to the thyroid). Although this
has not been shown to improve survival, it lowers the risk of local
recurrence (cancer coming back in the neck area). It also makes it
easier to accurately stage the cancer. If cancer has spread to other
neck lymph nodes, a modified radical neck dissection (a more extensive
surgical removal of lymph nodes from the neck) is often done.
Radioactive iodine therapy is often used to destroy any
remaining thyroid tissue after surgery and to treat any undetectable
cancer remaining in the neck or elsewhere in the body that takes up
iodine. External radiation may be used for cancers that do not take up
iodine. Thyroid hormone therapy is used as well.
Recurrent cancer:
Treatment of cancer that comes back after initial therapy depends
mainly on where the cancer is, although other factors may be important
as well. If the cancer recurrence can be located and appears to be
resectable (removable), surgery is often used. If the cancer shows up
on a radioiodine scan (meaning the cells are taking up iodine),
radioiodine therapy may be used, either alone or with surgery. If the
cancer does not show up on the radioiodine scan but is found by other
imaging tests such as magnetic resonance imaging or positron emission
tomography scan, external radiation may be used. Chemotherapy may be
tried if the cancer has spread to several places and radioiodine is not
helpful, although doctors are still trying to find effective drugs for
this disease. Another option is taking part in a clinical trial of
newer treatments.
Follicular and Hürthle cell
carcinoma
Stages I to IV:
Most doctors recommend near-total or total thyroidectomy for these
types of thyroid cancer. This surgery makes radioactive iodine
treatment afterward more effective. As with papillary cancer, some
lymph nodes usually are removed and examined. If cancer has spread to
lymph nodes, a central compartment or modified radical neck dissection
(surgical removal of lymph nodes from the neck) may be done. Because
the thyroid is removed, patients will need thyroid hormone therapy as
well.
Radioiodine scanning is usually done after surgery to look for
areas still taking up iodine. Metastasis to nearby lymph nodes and to
distant sites can be treated by radioactive iodine. For cancers that
don't take up iodine, external beam radiation therapy may help treat
the tumor or prevent it from growing back in the neck.
Distant metastases may need to be treated with external beam
radiation therapy or chemotherapy if they do not respond to radioactive
iodine.
Recurrent cancer:
The options for treating cancer that comes back after initial treatment
are basically the same as they are for recurrent papillary cancer (see
above).
Medullary thyroid carcinoma
Most doctors advise that patients diagnosed with medullary
thyroid carcinoma (MTC) be tested for other tumors that are typically
seen in patients with the MEN 2 syndromes (see "What
are the risk factors for thyroid cancer?"), such as
pheochromocytoma and parathyroid adenoma. Screening for
pheochromocytoma is particularly important, since the unknown presence
of this tumor can make anesthesia and surgery extremely dangerous. If
they are forewarned, surgeons and anesthesiologists can medically
pre-treat the patient to make surgery safe.
Stages I and II:
Total thyroidectomy is the main treatment for MTC and often cures
patients with stage I or stage II MTC. Regional lymph nodes are usually
removed as well (central compartment or modified radical neck
dissection). Thyroid hormone therapy is always given, since after total
thyroidectomy the patient will not be able to make enough thyroid
hormone to stay healthy. Although thyroid hormone therapy reduces the
risk of papillary and follicular cancer recurrence, it does not reduce
the likelihood of MTC recurrence.
Because MTC cells do not take up radioactive iodine, there is
no role for radioactive iodine therapy in treating MTC. Still, some
doctors advise giving a dose of radioactive iodine to destroy any
remaining normal thyroid tissue. If MTC cells are in or near the
thyroid, this may affect them as well.
Stages III and
IV: Surgery is the same as for stages I and II (usually
after screening for MEN 2 syndrome and pheochromocytoma). Thyroid
hormone therapy is given afterward. When the tumor is extensive and
invades many nearby tissues or cannot be completely removed, external
beam radiation therapy may reduce the chance for recurrence in the
neck.
Recurrent
cancer: Surgery, external radiation therapy, or
chemotherapy may be needed to treat recurrent disease in the neck or
elsewhere. Clinical trials of new treatments may be another option if
standard treatments aren't effective.
Genetic testing
in medullary thyroid cancer: If you are told that you
have MTC, even if you are the first one in the family to be diagnosed
with this disease, ask your doctor about genetic counseling and
testing. Genetic testing can find mutations in the RET gene -- seen in
cases of familial MTC and the MEN 2 syndromes. If you have one of these
mutations, it's important that family members (children, brothers, and
sisters) be tested as well. Because almost all children and adults with
positive genetic test results will develop MTC at some time, doctors
generally agree that thyroidectomy to prevent MTC should be done soon
after positive testing, even in children. Some would say especially in
children, since some hereditary forms of MTC affect children and
pre-teens. Total thyroidectomy can indeed prevent this cancer in
carriers who have not yet developed it. Of course, this means that
lifelong thyroid hormone replacement will be needed.
Anaplastic carcinoma
Stage IV (note:
all anaplastic thyroid cancers are classified as stage IV): Surgery
may or may not be used to treat this cancer, because it is often
widespread at the time of diagnosis. If the cancer is confined to the
local area around the thyroid, which is rare, total thyroidectomy may
be done. The goal of surgery is to remove as much cancer as possible in
the neck area, ideally leaving no cancer tissue behind. Because of the
way anaplastic carcinoma spreads, this is often difficult or
impossible. Local spread to essential structures within the neck (the
windpipe, arteries, etc.) is responsible for most deaths from this type
of thyroid cancer.
External beam radiation therapy, alone or combined with
chemotherapy, may be used:
- to treat the disease before surgery in order to increase
the chance of complete tumor removal
- after surgery to try to control any disease that remains in
the neck
- in cases where the tumor is too large or widespread to be
treated by surgery
If the cancer is causing (or may eventually cause) trouble
breathing, a hole (tracheostomy) may be placed surgically in the front
of the neck to bypass the tumor and allow the patient to breathe more
comfortably.
For cancers that have spread to distant sites, chemotherapy
may be used, sometimes along with radiation therapy if the cancer is
not too widespread. Clinical trials of newer treatments are an option
as well.
Last Medical Review: 04/28/2009 Last Revised: 05/14/2009
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