Thyroid cancer is the most common endocrine malignancy and its incidence has increased two-and-a-half-fold over the last 20 years in our locality. There are basically 4 types of thyroid cancer with variation of biological aggressiveness and prognosis. Types of thyroid carcinoma (with increasing degree of aggressiveness):

1. Well-differentiated thyroid carcinoma
     - Papillary thyroid carcinoma
     - Follicular thyroid carcinoma

2. Medullary thyroid carcinoma
3. Undifferentiated (anaplastic) thyroid carcinoma
4. Others: lymphoma, squamous cell carcinoma

Well-differentiated thyroid carcinoma has a relatively good prognosis after appropriate treatment but can de-differentiate to anaplastic carcinoma with invariably poor prognosis despite all available treatments. Total thyroidectomy is adopted for the majority of patients with differentiated thyroid cancer while hemithyroidectomy is increasingly performed for low-risk cancers or microcarcinomas. Central nodal dissection is performed selectively for patients with papillary thyroid carcinoma while lateral neck dissection is performed on therapeutic basis for patients with clinical or sonographic evidence of cervical nodal metastases. For patients with upper neck node involvement, a separated small skin crease incision is usually preferred in the upper neck instead of a large single hockey stick incision. Complex laryngotracheal resection should be performed for locally advanced cancer. Adjuvant radioactive iodine treatment followed by whole body scintigraphy is administered for selected patients, while external beam irradiation is reserved for those after incomplete excision. Patients are closely followed up for potential recurrence and distant metastases.