Click here for Frequently Asked Questions on the Treatment of Thyroid Cancer.

A surgical procedure is required for the treatment of patients with thyroid cancer. The extent of surgery will depend on the suspected pathological diagnosis and the size of the nodule (putative tumor), and is often influenced by the results of the preliminary tumor analysis intra-operatively during a 'quick-section' analysis of tumor histology. The nature and extent of thyroid surgery for thyroid cancer may vary from center to center and should be discussed prior to surgery with an experienced thyroid surgeon. Patients should be aware that a diagnosis made at quick section is not always accurate. It is uncommon for a diagnosis of benign adenoma to be made at quick section, only to have the final pathology report come back as thyroid cancer. In such instances, an additional operation may then be required to remove the remaining thyroid tissue.

Complications and risks of removing most of the thyroid (subtotal thyroidectomy) include the risks of general anesthesia, damage to local nerves, including the recurrent laryngeal nerve that innervates the vocal cords, and hypocalcemia (low levels of calcium in the blood), if extensive damage to or resection of all 4 parathyroid glands occurs. In some instances, a search for lymph nodes surrounding the thyroid may also be carried out (lymph node dissection). As is the case with many surgical procedures, the experience of the thyroid surgeon will greatly influence the complication rate during surgery. Wherever possible, patients are advised to seek a surgeon with extensive experience in thyroid surgery. Depending on the type of operation, stay in hospital may range from several hours to a few days. In many centers, patients undergoing a partial or hemi-thyroidectomy, may be discharged home several hours after the surgical procedure. In contrast, patients undergoing more extensive surgery may be hospitalized for several days, especially if hypocalcemia (low calcium) develops postoperatively. For more information, see the section on Thyroid Surgery.

Radioactive iodine is often administered to ablate or destroy the few normal remaining normal thyroid cells that were not removed at the time of surgery. Radioactive iodine may also destroy any remaining clusters of thyroid cancer cells. The amount of radioactive iodine administered depends on the type and size of tumor, the initial extent of surgery, and the presence or absence of suspected residual tumor. In some instances, radioactive iodine for thyroid remnant ablation may be administered as an outpatient. In other treatment indications or regimens, patients may be administered a somewhat larger radioactive iodine dose that may require hospitalization for 48-72 hrs or so, depending on the dose administered.

Following surgery and radioactive iodine treatment, patients will usually take thyroid hormone in the form of thyroxine in a dose sufficient to keep their TSH level in the suppressed range.

FAQs

I have a small thyroid cancer less than 10 mm in size. Does it have to be treated?

Most thyroid cancer experts would recommend traditional treatment involving at least surgical removal of the thyroid gland. However, some patients have elected not to be treated and have been followed by their physicians. It appears that many patients with very small thyroid cancers will have minimal growth of the small thyroid cancers over several years observation, however there is no scientific randomized clinical trial data available to support decision making in this area. See An observation trial without surgical treatment in patients with papillary microcarcinoma of the thyroid. Thyroid. 2003 Apr;13(4):381-7. Although the prognosis is clearly excellent for patients with small tumors, the required extent of surgery and the potential need for radioactive iodine has not been clearly defined in randomized studies Papillary thyroid microcarcinoma (PTMC): Prognostic factors, management and outcome in 403 patients.
Eur J Surg Oncol. 2006 Jul 25; [Epub ahead of print]. However patients with small tumors confined to the thyroid appear to do well independent of whether they receive radioactive iodine, as outlined in Outcomes of patients with differentiated thyroid carcinoma following initial therapy. Thyroid. 2006 Dec;16 (12):1229-42.

I have heard that some less well differentiated more aggressive thyroid tumors that don't take up radioactive iodine can be treated with Vitamin A?

A subset of tumors appear to respond to the class of drugs known as retinoids. In some studies, patients treated with Patients with advanced thyroid cancer and without the therapeutic options of operation or radioiodine therapy were treated with 13- cis-retinoic acid at a dosage of 1.5 mg/kg body weight daily appear to show a response, with tumor regression and in some cases, increased radioactive iodine uptake by the tumors. A response was detected in about 38 % of cases in a pilot study over 5 weeks. See Clinical impact of retinoids in redifferentiation therapy of advanced thyroid cancer: final results of a pilot study. Eur J Nucl Med Mol Imaging. 2002 Jun;29(6):775-82. Subsequent observational studies of larger patients have shown less impressive results using this type of "differentiation therapy" as shown in Retinoic acid for redifferentiation of thyroid cancer - does it hold its promise? Eur J Endocrinol. 2003 Apr;148(4):395-402.

Has the outcome and survival statistics for well differentiated thyroid cancer (WDTC) changed over the last few years?

A study at the Mayo clinic documents trends in the diagnosis, treatment and outcome of patients with WDTC. The prognosis for this disease was excellent in most patients several decades ago, and remains comparably  favorable over recent years. See Papillary Thyroid Carcinoma Managed at the Mayo Clinic during Six Decades (1940-1999): Temporal Trends in Initial Therapy and Long-term Outcome in 2444 Consecutively Treated Patients. World J Surg. 2002 May 21.

I have only had half my thyroid removed and the pathology report showed cancer. Do I need to have a second operation or can radioactive iodine be used in my situation?

The answer to this question is a matter of some debate. If the pathology report shows a large tumor, with aggressive features such as lymph node involvement, most physicians would strongly recommend completion thryoidectomy and removal of the remaining thyroid lobe. On the other hand, if the pathology shows a small well differentiated thyroid cancer, there is some evidence that low dose outpatient radioactive iodine can be used to ablate the remaining thyroid lobe, as outlined in Radioactive iodine lobe ablation as an alternative to completion thyroidectomy for follicular carcinoma of the thyroid. Thyroid. 2002 Nov;12(11):989-96.

What stage is my thyroid cancer?

There are various staging or classification systems used by different experts, some of which are reproduced below.

 T - primary tumor
    T0 - no palpable tumor
    T1 - single tumor confined to the gland; no deformity
    T1 - multiple tumors confined to the gland; no deformity
    T2 - multiple tumors or a single tumor producing deformity of the gland
    T3 - tumor extending beyond the gland

N - regional lymph nodes
    N0 - no palpable nodes
    N1 - movable homolateral nodes
    N2 - movable contralateral or bilateral nodes
    N3 - fixed nodes

M - distant metastases
    M0 - no evidence of distant metastases
    M1 - distant metastases present

OR

Clinical Stage                       TNM Classification
I: Intrathyroidal                      T0, T1, T2, N0, M0
II: Cervical adenopathy (lymph nodes)        T0--T2, N0--N2, M0
III: Locally invasive disease T3, N3, M0
IV: Distant metastases (cancer spread outside neck)      M1

MACIS Score

(Only applicable for papillary cancer)

Large retrospective studies have been carried out and analyzed statistically. One of these studies emanates from the Mayo Clinic (Predicting outcome in papillary thyroid carcinoma: development of a reliable prognostic scoring system in a cohort of 1779 patients surgically treated at one institution during 1940 through 1989. Surgery. 1993 Dec;114(6):1050-7;).

 M stands for metastasis, A for Age, C for complete resection, I for invasive and S for Size.

 

M + 3 if Metastasis is found
A <= 39 years of age = 3.1. = 40 = Age (y) x 0.08
C + 1 if resection is inComplete
I + 1 if Invasive growth (pathologists report)
S 0.3 x largest diameter in centimeters (Size)

 

Prognostic score  20 year survival
< 6 99 %
6 - 6 89 %
7 - 8 56 %
> 8 24 %

Thyroid cancer is viewed as a disease of younger people. Can older individuals get thyroid cancer also?

Thyroid cancer is not uncommon in older patients. In one study, subset analysis of thyroid cancer presentation and outcomes suggested that the disease presents with similar features in older patients, with a slightly higher rate of metastatic disease at the time of initial diagnosis. See Long-term results in elderly patients with differentiated thyroid carcinoma. Cancer. 2003 Jun 1;97(11):2736-42.