anaplastic thyroid carcinoma(redirected from undifferentiated carcinoma of thyroid)
anaplastic thyroid carcinomaThe most aggressive of all thyroid malignancies, which accounts for only 2–5% of thyroid carcinomas but 40% of thyroid cancer-related deaths. The typical history is of a rapid increase in size of a long-standing cold thyroid nodule in an elderly patient; it is more common in iodine-deficient geographic regions and in a background of prior thyroid pathology (e.g., goitre or thyroid cancer); up to 80% have a history of well- (papillary, follicular) or poorly differentiated thyroid carcinoma. Local invasion (e.g., trachea, oesophagus) is common.
Hoarse voice, cough, haemoptysis, tracheal obstruction; physical exam may reveal nodules in thyroid.
Thyroid function is usually normal.
Generally palliative; 50% are inoperable at the time of diagnosis; surgery, radiation and chemotherapy are essentially useless.
Anaplastic carcinoma is an aggressive disease with early metastases in lung (50% of cases), bone and brain; median survival is 4–6 months.