The parathyroid glands are small round glands that are attached to the thyroid gland, in the front of the neck. Their purpose is to produce parathyroid hormone. This is a substance that helps to regulate the amount of calcium in the blood.

Tumours of the parathyroid glands are uncommon and are usually benign (not a cancer). Probably only about one in fifty parathyroid tumours is cancerous so this means that a parathyroid cancer is a very rare condition. It is usually only diagnosed when a person has an operation for an overactive parathyroid gland (primary hyperparathyroidism).

The causes of parathyroid cancer are not fully understood but they have sometimes been linked to previous exposure to radiation.

The symptoms of these tumours include tiredness, muscle weakness, loss of appetite, irritability, pain in the bones and constipation. Sometimes the tumours produce an excess of parathyroid hormone which can cause calcium to be lost from the bones into the blood stream.

The main treatment for parathyroid cancer is surgery. If the surgeon recognises the possibility of a parathyroid cancer during an operation to remove an overactive parathyroid gland, he/she may choose to remove all thyroid and parathyroid tissue and some lymph glands from that side of the neck. It is important that all the tumour is removed to reduce the risk of the cancer coming back or spreading to other parts of the body. Sometimes radiotherapy is given following surgery to further reduce the chances of the cancer returning.

Radiotherapy (and occasionally chemotherapy) may also be helpful if a parathyroid cancer does recur or has spread to other parts of the body.

As the number of cases of parathyroid cancer is very small it is not possible to give precise figures for the outcome of treatment but many people are treated successfully and complete removal by surgery seems to give the best chance of cure.