Thyroid surgery typically involves a thyroidectomy, the removal of all or part of a diseased thyroid gland. Removal of only part of the gland is called a partial thyroidectomy. In some cases, total thyroidectomy is necessary where the entire gland is removed. A Subtotal thyroidectomy is removal of nearly the entire gland leaving only a small amount of thyroid tissue behind. Thyroid surgery is usually recommended for thyroid conditions such as nodules, cysts, overproduction of hormones, cancerous and noncancerous tumors, and goiter or swelling of the thyroid that can make it difficult to swallow or breathe.