Nonpalpable occult and metastatic papillary thyroid carcinoma

Current treatment of papillary thyroid microcarcinoma

PTMC is being diagnosed with increasing frequency and generally has an excellent prognosis with less than 0.5% disease-specific mortality. Better prognostic stratification, especially for high-risk patients, helps to optimize surgical care. Older age, extrathyroidal invasion, lymph node involvement, and distant metastases are usually regarded as the most potent risk factors for patients with PTMC. Total or near-total thyroidectomy is advocated as the initial therapy for most primary PTMCs, whereas neck dissection is only recommended with the presence of cervical lymphadenopathy or T4 tumors. ATA suggests that postoperative RAI ablations be administrated to patients with gross extrathyroidal invasion or distant metastases. RAI ablation may also facilitate the use of serum Tg concentrations for postoperative risk assessment.

Papillary thyroid microcarcinoma: A surgical perspective

Papillary thyroid microcarcinoma (PTMC) is defined as a papillary thyroid cancer measuring less than 10mm in its greatest diameter. It is the most common form of thyroid cancer, detected in up to 36% in autopsy studies. The wide availability and use of neck ultrasonography in the evaluation of carotid arteries and of the thyroid resulted in an increased detection of PTMC. PTMC is often multifocal. The diagnosis is usually based on a combination of clinical examination, laboratory investigations, and specialized radiological techniques (mainly neck ultrasonography combined with fine-needle aspiration cytology). A common scenario is the diagnosis of PTMC as an incidental finding following thyroidectomy for a presumably benign thyroid disease. Despite some controversy, most authors agree that PTMC should be treated by total or near-total thyroidectomy, provided it can be performed safely. Because of its many and major advantages, in our clinical practice, total or near-total thyroidectomy is the procedure of choice for the management of PTMC. Given the high incidence of PTMC as an incidental finding and the frequent multi-focality, we also favor total or near-total thyroidectomy for the surgical management of nodular thyroid disease (multinodular goiter or dominant presumably benign thyroid nodule/s). Despite some controversy, we perform central neck lymph node dissection electively, in the presence of cervical lymphadenopathy. Radioiodine ablation therapy may be used as an adjuvant therapy. Prognostic factors (such as tumor multicentricity, positive lymph nodes, capsular or vascular invasion) or scoring systems (such as the AMES) can be used to select patients for radioiodine adjuvant therapy. Suppression therapy is needed after surgical management. Despite the potential for neck lymph node and even distant metastases, the biological behavior of PTMC is in general benign and the prognosis is very good.

Surgical considerations and controversies in thyroid and parathyroid surgery

The techniques of thyroid surgery have been fully elucidated in several surgical texts and atlases. This article discuss surgical pearls of thyroid and parathyroid surgery. We discuss preoperative, intraoperative, and postoperative considerations and controversies for both procedures.

Well-differentiated carcinoma of the thyroid

Thyroid cancer will be diagnosed in more than 20,000 individuals in the United States in 2002. Approximately 16,000 of these patients will be women. During the same year, an estimated 1300 deaths from thyroid cancer are expected. The various types of thyroid cancer include papillary carcinoma, follicular carcinoma, Hurthle cell carcinoma, medullary carcinoma, anaplastic carcinoma, and thyroid lymphoma. Papillary, follicular, and Hurthle cell carcinoma are considered well-differentiated thyroid cancers and constitute the focus of this article.

Long-standing lateral neck mass as the initial manifestation of well-differentiated thyroid carcinoma

OBJECTIVE

To analyze the presentation, evaluation, and treatment of a subset of patients with well-differentiated thyroid carcinoma who present with a lateral neck mass and no palpable disease in the thyroid gland.

STUDY DESIGN

A retrospective review of all patients undergoing thyroidectomy for malignancy.

METHODS

A database of all thyroidectomies performed for malignancy by the Vanderbilt University Department of Otolaryngology-Head and Neck Surgery from 1992 to 1997 was created. Patients who presented with an isolated neck mass without evidence of palpable disease in the thyroid were selected for the study population.

RESULTS

There were 60 cases of thyroid malignancy, with 14 cases (23.3%) that presented as isolated lateral neck mass. The characteristics of this group (compared with the population of all thyroid malignancies) include younger age at presentation (37.7 +/- 15.2 y vs. 49.8 +/- 15.6 y; Student t test: P = .019) and long-standing presence of symptoms (27.4 +/- 39.6 mo vs. 3.6 +/- 3.9 mo; P = .023). These patients generally presented from a referring facility after having an excisional biopsy, which was 100% accurate. Fine-needle aspiration is becoming more useful and was 66.7% accurate. Histological examination revealed cancer in the thyroid gland in all patients, 11 cases of papillary carcinoma, 2 follicular carcinomas, and one medullary carcinoma The mean size of the primary focus was 10.9 +/- 8.7 mm, with 29% demonstrating bilateral disease and 14% demonstrating multifocal disease in the ipsilateral gland. The neck specimens revealed an average of 5.3 +/- 3.2 metastatic nodes in levels II-IV and 3.9 +/- 4.6 metastatic nodes in the paratracheal region.

CONCLUSION

Based on this patient population, the long-standing lateral neck mass in the young patient should raise the physician's index of suspicion for thyroid carcinoma Fine-needle aspiration should be used in conjunction with judicious excisional biopsy. The bilateral and multifocal nature of otherwise occult primary disease argues for total thyroidectomy in this setting.

Papillary microcarcinoma of the thyroid gland

Papillary microcarcinomas are a specific subgroup of papillary thyroid cancer. They have the same histological features as papillary thyroid cancer but are 1.0 cm or less in diameter. These tumours are a common incidental finding at autopsy and in thyroid glands excised for other pathology. This tumour can metastasize to regional lymph nodes but its ability to cause significant morbidity and mortality has been questioned. As papillary microcarcinomas can represent up to 30 per cent of all papillary cancers seen in a thyroid surgeon's practice, they are an important group. The aim of this review article is to outline the natural history of papillary microcarcinoma and to offer therapeutic management strategies.

A case report of occult thyroglossal duct carcinoma

A 50-year-old male had an occult thyroglossal duct carcinoma in the thyroglossal duct remnant attached to the upper pole of a thyroglossal duct cyst which was noticed due to extravasation of the cyst. After the patient had been struck into the thyroid cartilage with the tip of a bamboo sword while practicing Japanese fencing. The authors emphasize again that the important matter in the treatment of thyroglossal duct cysts is the removal of the whole thyroglossal duct remnant with the central portion of the hyoid bone according to Sistrunk's method in order to prevent not only recurrence of the thyroglossal duct cyst but also not to overlook any microcarcinoma.

Highly aggressive behaviour of occult papillary thyroid carcinoma

Occult papillary thyroid carcinoma is generally associated with an excellent prognosis. Distant metastasis of this tumour is extremely rare. A case of occult papillary thyroid carcinoma with metastases to the lungs, cervical lymph nodes, skeleton, and the brain is reported. The tumour expressed itself in extremely aggressive clinical behaviour and responded only partially to aggressive therapy. The controversial methods of treatment for occult papillary thyroid carcinoma are also discussed.