Tumors that produce too much thyroid-stimulating hormone (TSH, or thyrotrophin) can cause the thyroid gland to become overactive, a condition known as hyperthyroidism. A TSH-producing tumor is one of the rarest types of pituitary tumors.
Pituitary tumors can also secrete reproductive hormones such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These are called gonadotropin-secreting tumors, and they are treated similarly to tumors that produce TSH.
If you have a TSH-producing tumor, your symptoms may include:
- rapid heart rate
- unexplained weight loss
- increased appetite
- feeling too warm or hot
- trouble falling asleep
- frequent bowel movements
- a lump in the front of the neck (due to an enlarged thyroid gland)
If your doctor suspects a TSH- or gonadotropin-producing tumor, a blood test will be necessary to measure the levels of each in your blood. An MRI scan may also be used to determine the size and exact location of the tumor.
The primary therapy for both tumors that produce TSH and gonadotropin-secreting tumors is surgery. At Memorial Sloan Kettering, we use a minimally invasive approach called transnasal transsphenoidal resection to remove pituitary tumors. Surgeons are able to bypass brain tissue, operating instead through an incision inside the nasal passage. The risk for neurologic complications with this approach is very low, and the surgery leaves no visible scar.
If surgery alone is not curative, radiation therapy may be an option. Forms of radiation therapy we may recommend include stereotactic radiosurgery, in which special equipment is used to give a single large dose of radiation to a tumor. We may also recommend intensity-modulated radiation therapy, which uses radiation beams of varying intensity to precisely match tumor angles and shapes and thereby reduce the risk of damage to optic nerves and other delicate structures in this area.