What type of doctor does a thyroidectomy?

Surgeons/ENT. An ear nose and throat (ENT) doctor or a surgeon can do this surgery.
Surgical oncologists. Until the last decade, general surgeons did most thyroidectomies. Recently, many ENT programs offer substantial experience. Surgical oncologists typically have head and neck and endocrine experience. Bottom line - ask about the number of thyroidectomies a surgeon performs each year. Numerous studies show that "occasional" thyroid surgeons have more complications. This is most important for cancer.