A 43-year-old woman presented with fatigue and reported a weight loss of 22.5 kg (50 lb) during the previous 18 months. Physical examination revealed diaphoresis, cachexia, a resting heart rate of 110 beats per minute, and a diffusely enlarged, nontender thyroid gland.
She also had lid retraction, mild proptosis, and conjunctival injection. The patient had been aware of a mass growing in the anterior neck for the previous 6 years and had more recently noted hair loss, heat intolerance, and a resting tremor.
What’s the diagnosis ?
