USMLE/COMLEX - Step 2 - TSH-Secreting Pituitary Adenomas

USMLE/COMLEX - Step 2 - TSH-Secreting Pituitary Adenomas TSH-secreting pituitary adenomas are rare pituitary gland tumors that produce excess thyroid-stimulating hormone (TSH), leading to hyperthyroidism. The exact pathophysiology of these tumors follows several proposed mechanisms, including mutations in the GNAS gene and increased expression of the TSH? subunit gene. Other factors contributing to their development include genetic abnormalities, hormonal and environmental factors, and epigenetic changes. Rapid or irregular heartbeat Tremors or shakiness Weight loss despite increased appetite Heat intolerance or increased sweating Nervousness or anxiety Fatigue or weakness Difficulty sleeping or insomnia Changes in the menstrual cycle Elevated thyroid hormone levels Decreased thyroid-stimulating hormone levels Enlargement of the thyroid gland Tachycardia Tremors Weight loss despite increased appetite TFTs MRI Visual field testing Thyroid uptake and scan Biopsy The treatment of TSH-secreting pituitary adenomas typically involves a combination of medical therapy, surgery, and radiation therapy. The specific treatment approach depends on several factors, including the size and location of the tumor, the patient's age and overall health, and the severity of symptoms. 1. Medical therapy: The first-line treatment for TSH-secreting pituitary adenomas is usually medication to reduce thyroid hormone and TSH levels. These medications include thyroid hormone synthesis inhibitors (such as methimazole or propylthiouracil) and somatostatin analogs (such as octreotide or lanreotide), which can help decrease TSH secretion and reduce the size of the tumor. 2. Surgery: Transsphenoidal surgery, a minimally invasive procedure to remove the tumor through the nose or mouth, is often recommended for patients with large or symptomatic tumors that do not respond to medical therapy. Surgery can also be used as a first-line treatment in some cases. 3. Radiation therapy: Radiation therapy may be recommended in cases where the tumor cannot be completely removed with surgery or if the tumor recurs after surgery. Radiation therapy can be delivered as external beam radiation or stereotactic radiosurgery. 4. Follow-up care: Patients with TSH-secreting pituitary adenomas require long-term monitoring of thyroid function and pituitary function and regular imaging studies to monitor the tumor size.