Thyroid Cancer Surgical Practice Guidelines

Scope and Format of Guidelines

The Society of Surgical Oncology surgical practice guidelines focus on the signs and symptoms of primary cancer, timely evaluation of the symptomatic patient, appropriate preoperative evaluation for extent of disease, and role of the surgeon in diagnosis and treatment. Separate sections on adjuvant therapy, follow-up programs, or management of recurrent cancer have been intentionally omitted. Where appropriate, perioperative adjuvant combined-modality therapy is discussed under surgical management. Each guideline is presented in minimal outline form as a delineation of therapeutic options.

Since the development of treatment protocols was not the specific aim of the Society, the extensive development cycle necessary to produce evidence-based practice guidelines did not apply. We used the broad clinical experience residing in the membership of the Society, under the direction of Alfred M. Cohen, MD, Chief, Colorectal Service, Memorial Sloan-Kettering Cancer Center, to produce guidelines that were not likely to result in significant controversy.

Following each guideline is a brief narrative highlighting and expanding on selected sections of the guideline document, with a few relevant references. The current staging system for the site and approximate 5-year survival data are also included.

The Society does not suggest that these guidelines replace good medical judgment. That always comes first. We do believe that the family physician, as well as the health maintenance organization director, will appreciate the provision of these guidelines as a reference for better patient care.

Society of Surgical Oncology Practice Guidelines: Thyroid Cancer

Symptoms and Signs

Early-stage disease

• Asymptomatic
• Mass in the thyroid region
• Presence of enlarged lymph node in the supraclavicular region
• Vague pain or discomfort in the thyroid region

Advanced-stage disease

• Cervical lymphadenopathy
• Large mass in the thyroid region
• Rapidly increasing thyroid nodule
• Change in voice
• Difficulty in breathing
• Difficulty in swallowing

Evaluation of the Symptomatic Patient

Work-up

• Clinical evaluation, physical examination, complete head and neck examination, including indirect laryngoscopy
• Risk factor analysis
• Fine-needle aspiration (FNA)
• Ancillary diagnostic work-up if necessary
• Thyroid function tests
• Ultrasound, thyroid scan, and CT scan in selected patients

Appropriate timeliness of surgical referral

• Initial work-up should include a thorough and detailed clinical examination and evaluation of the physical findings.
• FNA should be considered the first diagnostic test.
• Evaluation of a solitary thyroid nodule
1. If FNA is benign, begin levothyroxine for 3 to 6 months.
• If lesion regresses or is unchanged, follow clinically.
• If lesion increases in size, operate.
2. If FNA shows follicular neoplastic cells, obtain a thyroid scan.
• If scan reveals a "cold" nodule, operate.
• If scan reveals a "hot" nodule, observe.
3. If FNA shows malignant or suspicious cells, operate.

Preoperative Evaluation for Extent of Disease

Physical examination

Indirect laryngoscopy

Chest x-ray

Baseline thyroglobulin for papillary cancer and calcitonin for medullary cancer

Role of the Surgeon in Initial Management

Evaluation of the symptomatic patient

• Clinical examination
• Indirect laryngoscopy with fiberoptic laryngoscope if necessary
• FNA of the neck or thyroid mass
• Chest x-ray for evaluation of the airway

Diagnostic procedures

• FNA

Surgical considerations: well-differentiated (papillary and follicular) thyroid cancer

• Risk group analysis is very helpful.
1. Age
2. Grade
3. Extracapsular extent of disease and tumor Size (AGES)
4. Presence of distant Metastasis
5. Extracapsular spread of disease and tumor Size (AMES)
• Surgical procedures
1. Lobectomy and isthmectomy
2. Subtotal thyroidectomy
3. Near total thyroidectomy
4. Total thyroidectomy
5. Modified neck dissection in selected patients

Surgical considerations: medullary carcinoma of the thyroid

• Total thyroidectomy with appropriate neck dissection should be performed if nodes are clinically palpable.
• Central compartment clearance is extremely important.

Surgical considerations: anaplastic thyroid cancer

• Diagnosis can be made based on clinical suspicion of a rapidly growing mass, age of the patient, unusual symptoms, a rapidly growing mass in the central compartment of the neck and fixed to the surrounding structures, and airway problems.
• FNA will raise suspicion of anaplastic thyroid cancer.
• Confirmation of the diagnosis can be made by either open biopsy or Tru-cut needle biopsy (core biopsy).
• Treatment should consists of the combination of chemotherapy (including doxorubicin(Drug information on doxorubicin)) and external radiation therapy.
• The role of surgery is very limited.
• Occasional patients may need a tracheostomy. (Most of these patients will do very poorly.)

These guidelines are copyrighted by the Society of Surgical Oncology (SSO). All rights reserved. These guidelines may not be reproduced in any form without the express written permission of SSO. Requests for reprints should be sent to: James R. Slawny, Executive Director, Society of Surgical Oncology, 85 West Algonquin Road, Arlington Heights, IL 60005.

Although thyroid cancer is not of the more common tumors, it accounts for 90 % of tumors originating in the endocrine glands. Approximately 16,000 patients with thyroid cancer are seen every year, and 1,200 patients die from this cancer annually.

The most important risk factor for thyroid cancer is a history of radiation to the neck. The most common indications for neck irradiation include acne and other skin conditions and an enlarged tonsil or thymus. The incidence of thyroid cancer is slightly higher in patients with Graves' disease and thyroiditis.

There are four main types of thyroid cancer: papillary, follicular, medullary, and anaplastic. The differentiated thyroid cancers (papillary and follicular) account for less than 90% of all thyroid malignancies, while medullary and anaplastic represent 5% to 10% and greater than 5% of cases, respectively. Hurthle cell cancers were formerly included in the differentiated group, but the World Health Organization has eliminated Hurthle cell tumor as a separate category and included it as a variant of follicular thyroid cancer.

Papillary cancer is more common in younger individuals (those in the second and third decades of life), while anaplastic thyroid cancer is uniformly seen in the sixth and seventh decades. Follicular cancer is more common in endemic regions, such as Europe. The majority (approximately 80%) of patients with medullary cancer have a sporadic form of the disease, and the remaining 20% have familial disease.

The most common presentation is an asymptomatic mass in the thyroid region. Occasional patients, particularly those 20 to 35 years old or those over age 60, may present with enlarged supraclavicular lymph nodes. Patients with advanced-stage disease may present with massive cervical lymphadenopathy, a large, fixed mass in the thyroid region, or a change in voice. Occasionally, the patient may exhibit difficulty in breathing or swallowing on presentation.