1. DIAGNOSTIC EVALUATION
2. EXAMINATION UNDER ANESTHESIA AND BIOPSY
3. TREATMENT
4. ADJUVANT THERAPY
5. FOLLOW UP
6. BIBLIOGRAPHY

I. DIAGNOSTIC EVALUATION:

Clinical Evaluation:

• Complete history and physical examination
  
  Includes history of exposure to ionizing radiation, family history of thyroid cancer or other thyroid abnormalities. The presence or absence of hoarseness, dysphagia and stridor should be documented.

• Complete history and physical examination 
  
  Includes inspection and palpation of the thyroid gland as well as the lateral aspects of the neck for cervical lymphadenopathy. The characteristics of the palpable thyroid mass such as size, consistency, number and fixation to trachea or larynx must be documented, as well as the presence of extrathyroidal extension to involve soft tissues in the central compartment of the neck or the skin. The examination should include laryngoscopy to document the mobility of the vocal cords.
  
  If enlarged lymph nodes are present, their location (Group or Level I - VI), number, size, mobility, relationship to adjacent structures and staging should be documented.
• Biopsy of primary
  
  Fine needle aspiration biopsy of the thyroid nodule or enlarged neck node is desirable to establish tissue diagnosis. However, if clinical history and physical findings are suspicious for a neoplastic process, one may forego fine needle aspiration biopsy.

Imaging Studies:

• Ultrasound examination of the thyroid gland (Optional)

  It permits identification and documentation of accurate size and number of thyroid nodules. It also differentiates between a cystic and a solid nodule.

• Thyroid scan (Optional)

  This demonstrates the functional nature of the nodule (hot or cold). It may also demonstrate more than one nodule which may not be palpable. 

• Chest radiographs, PA and lateral 

  To evaluate for metastatic disease.

• MRI or CT scan

  Indicated when there is suspicion of tumor extending into the larynx or trachea or into the mediastinum. MRI is preferable because the iodine contrast used for CT scanning may delay postoperative radioactive iodine therapy. An MRI scan is particularly helpful for retrosternal tumors. 

Laboratory Tests:

• Routine preoperative laboratory tests as required by institutional guidelines
• Thyroid function studies to include T3, T4, TSH levels
• Thyroglobulin level

Consultations:

• Endocrinology

  This may be required depending on individual patterns of practice regarding evaluation or follow up of patients with thyroid cancer.

• Internal Medicine, Cardiology or Anesthesiology

  When a disease is present which may affect the use of general anesthesia. 

• Nuclear Medicine (Postoperatively)

  When treatment with radioactive iodine is felt to be indicated. 

• Radiation Oncology (Postoperatively)

  Whenever difficulty was encountered removing all gross tumor in the central compartment in the neck, postoperative radiation may be considered.

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Examination under anesthesia is seldom necessary for adequate evaluation of a thyroid nodule. Tissue diagnosis is usually secured with a fine needle aspiration biopsy or by thyroid lobectomy and frozen section examination at the time of surgery.

 Primary tumor:

Several retrospective studies involving large numbers of patients with thyroid cancer have identified a number of prognostic factors. These prognostic factors are related to the patient and the tumor. The patient related factors are age and gender and the tumor related factors are size, extrathyroidal extension, histology (grade) and the presence of distant metastasis and the adequacy of the resection. These prognostic factors are useful for risk group stratification. Young patients with favorable tumors are in the low risk category. A great majority of patients with differentiated carcinoma fall in the low risk category. While many surgeons feel that these prognostic factors should be employed in the selection of treatment of the primary tumor (i.e. the extent of thyroidectomy), controversy still exists about the role of lobectomy or total thyroidectomy in the treatment of differentiated thyroid cancers. Most surgeons agree, however, that a lobectomy is appropriate for most patients in the low risk category. On the other hand, a total thyroidectomy is clearly indicated when the following conditions are present: 1) involvement of both lobes of the thyroid gland, 2) presence of distant metastasis, 3) massive tumor with extrathyroidal extension, 4) high risk patient with a high risk tumor.

Neck:

Elective regional lymph node dissection is not recommended. If, at the time of thyroidectomy, grossly enlarged lymph nodes are identified in the central compartment alone, a tracheo-esophageal groove (paratracheal) lymph node dissection is performed. When enlarged lymph nodes are clinically palpable or are encountered during surgery in the lateral compartment of the neck, a modified radical neck dissection (Levels II-V) with preservation of the accessory nerve, sternocleidomastoid muscle, and internal jugular vein is indicated.

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Postoperative adjuvant treatment consists of:

• Radioactive iodine scan, dosimetry and treatment are recommended in the following circumstances: (1) distant metastasis, (2) gross residual tumor following surgery, (3) high risk of local recurrence following total thyroidectomy for a large tumor, (4) after resection of multiple lymph node metastasis in the lateral compartment of the neck and superior mediastinum (5) after total thyroidectomy in "high risk" patients.

• Suppressive doses of levothyroxine are recommended in order to keep the TSH as low possible.

• External beam radiation therapy may be helpful in patients with residual tumor in the central compartment of the neck, particularly if the tumor uptake of radioactive iodine is poor.

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V. FOLLOW UP:

The follow up schedule depends on the patient's clinical course and individual risk factors. In general it is as follows: Once a month for the first three months after surgery, every 3 to 6 months for three years, thereafter every 6 - 12 months for up to ten years, then once a year for life. 

Follow up evaluations should include:

• Examination of the head and neck area

• Chest x-ray, yearly

• Serum thyroglobulin level, at least twice a year, in patients who have undergone total thyroidectomy

• TSH level as clinically indicated

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Hay ID, Grant CS, Taylor WF, McConahey WM. Ipsilateral lobectomy versus bilateral lobar resection in papillary thyroid carcinoma - a retrospective analysis of surgical outcome using a novel prognostic scoring system. Surg 1987, 102:1088-1095. 

Mazzaferri E, Thyroid carcinoma in a thyroid nodule. Finding a needle in a haystack. Am J Med, 1992, 93: 359.

Shah JP, Loree TR, Dharker D, et. al. Prognostic factors in differentiated carcinoma of the thyroid gland. Am J Surg, 1992, 64:658-661.

Shah JP, Loree TR, Dharker D, Strong EW. Lobectomy versus total thyroidectomy for differentiated carcinoma of the thyroid - A matched pair analysis. Am J Surg, 1993, 166:331-335.

Ross D, Long term management of well differentiated thyroid carcinoma. Endocrinol Metabol Clin NA 1990, 19: 719.

Rossi Rl, Nieroda C, Cady B, Wool MS. Malignancies of the thyroid gland, the Lahey Clinic Experience. Surg Cl NA, 1985, 65:211-230.

Shaha AR, Loree TR, Shah JP. Intermediate risk group for differentiated carcinoma of the thyroid. Surgery, 1994, 116:1036-1041.

Shaha AR, Loree TR, Shah JP. Prognostic factors and risk group analysis in follicular carcinoma of the thyroid gland. Surgery, 1995 (in press)

Tubiana M, Schlumberger M, Rougier P, et. al. Long term results and prognostic factors in patients with differentiated thyroid carcinoma. Cancer, 1985:55:794-804.

Tennval J, Biorkland A, Moller T, et. al. Is the EORTC prognostic index of thyroid cancer valid in differentiated thyroid carcinoma? Cancer, 1986, 57:1405-1414. 

American Joint Committee on Cancer. "Manual for Staging of Cancer". Fourth Edition, Philadelphia, JB Lippincott Co., 1993.

Shaha AR. Low risk differentiated cancer: the need for selective treatment. Ann Surg Onc, 1997, 4:328:333.

Shaha AR, Shah JP, Loree TR. Patterns of failure in differentiated thyroid cancer based on risk group analysis. Head Neck, 1998, 20:26-30.

Hundahl SA, Fleming ID, Fremgen AM, Menck HR. A National Cancer Data Base Report on 53,856 cases of thyroid carcinoma treated in the U.S., 1985-1995. Cancer, 1998;2638-48.

Hay ID, Bergstralh EJ, Goellner JR, et al. Predicting outcome in papillary thyroid carcinoma: Development of a reliable prognostic scoring system in a cohort of 1,779 patients surgically treated at one institution during 1940 through 1989. Surgery, 1993;114:1050-1058.

Mazzaferri EL, Jhiang SM. Long-term inpact of initial surgical and medical therapy on papillary and follicular thyroid cancer. Am J Med, 1994:97:418-428.