Anaplastic thyroid carcinoma (ATC) although rare is the most lethal form of thyroid cancer. The mortality rate for ATC is very high, with a median survival time of only 5 months; the survival rate at 1 year after diagnosis is <20%. Management of ATC is extremely difficult and rife with uncertainties. Herein, we describe a 75-year-old woman who presented with ATC and was successfully treated using concomitant treatment with docetaxel and high-dose radiotherapy. This case appears to be the first to have been reported in the literature involving complete remission of ATC confirmed by autopsy, suggesting the therapeutic potential of this combination.