Toxic adenomas

Question 1

What are toxic adenomas?

Answer 1

A benign, solitary nodule in an otherwise nonpalpable thyroid gland. Caused by a gain-of-function mutation of the TSH receptor gene in a single precursor cell, which results in autonomous production of thyroid hormones.

Question 2

What are the clinical features of toxic adenomas?

Answer 2

Hyperthyroidism

Question 3

How is toxic adenoma produced?

Answer 3

↑ T3 and ↓ TSH
Thyroid scintigraphy: solitary, hot nodule (due to increased uptake by the hyper-functioning nodule and suppression of the rest of the gland)

Question 4

What is the treatment of toxic adenoma?

Answer 4

Control symptoms with beta-blockers and thioamides
(Curative treatment) Radioactive iodine ablation or
Lobectomy or hemithyroidectomy (part of toxic mutinodular goiter)