Treatment for Hyperfunction of Endocrine Glands
Pharmacological Therapy
Pharmacological therapy involves the use of medications to either inhibit or block the synthesis or secretion of hormones, which is a common approach for treating endocrine gland hyperfunction. Examples include using imidazole or thiourea derivatives for the treatment of hyperthyroidism, dopamine receptor agonists for prolactinomas, and mitotane or metyrapone for cortisol excess (Cushing’s syndrome). Hormone receptor antagonists can also competitively inhibit the binding of hormones to their receptors, such as using spironolactone for primary hyperaldosteronism or cyproterone for central precocious puberty. Antagonistic effects between hormones are also utilized, such as somatostatin for treating growth hormone-producing tumors, insulinomas, glucagonomas, gastrinomas, and vasoactive intestinal peptide-producing tumors (VIPomas). Hormone analogs have therapeutic properties as well; gonadotropin-releasing hormone (GnRH) analogs, for instance, reduce gonadal hormone production and are used in conditions such as precocious puberty, polycystic ovary syndrome (PCOS), and endometriosis.
Surgical Treatment
Surgical interventions are performed to remove hormone-secreting tumors or hyperplastic glandular tissues in order to reduce excessive hormone synthesis and relieve local compressive symptoms. Conditions such as pituitary tumors, Graves' disease, autonomously functioning thyroid nodules, parathyroid adenomas, adrenocortical adenomas, and pheochromocytomas can all be treated with surgery. Perioperative measures are essential to stabilize vital signs, and postoperative evaluations of glandular function are necessary to determine whether hormone replacement therapy is required.
Radionuclide Therapy
Certain endocrine glands have the ability to concentrate specific compounds (generally substrates or substrate analogs involved in hormone synthesis). Radionuclide-labeled compounds can target and destroy endocrine tissues to achieve therapeutic effects. Endocrine tumor cells often express somatostatin receptors on their surface, allowing radionuclide-labeled somatostatin analogs to bind specifically to tumors. This approach, known as peptide receptor radionuclide therapy (PRRT), is employed for treating endocrine tumors, neuroendocrine tumors, and non-tumor endocrine gland hyperfunction. Examples include the use of 131I to treat Graves’ disease and 131I-MIBG for pheochromocytomas.
Radiation Therapy
Radiation therapy often serves as an adjunct to surgery and pharmacological treatments. X-rays, gamma rays, and charged particles such as electrons, protons, and heavy ions can be used for treating endocrine gland tumors. Ionizing radiation damages the DNA of tumor cells in the target region, leading to cell death or growth inhibition. For instance, residual tumor tissue in growth hormone-secreting pituitary adenomas can be treated with radiation therapy after surgery.
Interventional and Ablation Therapy
Highly selective arterial embolization or ablation therapy is used when conventional surgery is not feasible or when pharmacological therapy is not well-tolerated. This approach is suitable for adrenal, thyroid, parathyroid, and pancreatic tumors.
Molecular Targeted Therapy
The development of many endocrine tumors (or cancers) is associated with the activation of proto-oncogenes or the inactivation of tumor suppressor genes. Molecular targeted therapies aimed at these genes may be effective in treating such endocrine tumors. Advances in the understanding of the molecular mechanisms underlying thyroid cancer have led to the development of a range of targeted drugs, such as tyrosine kinase inhibitors (TKIs), BRAF inhibitors, and RET inhibitors. Research has demonstrated that these molecular targeted drugs effectively inhibit the growth of thyroid cancer cells and have shown promising results in treating advanced thyroid cancers. For neuroendocrine tumors with local progression or distant metastasis, therapies targeting the mTOR pathway represent a novel effective option.
Immunotherapy
With the widespread application of immune checkpoint inhibitors (ICIs) in oncology, research on immunotherapy for endocrine tumors (or cancers) is gaining increasing attention.
Treatment of Hypofunction of Endocrine Glands
Hypofunction of endocrine glands may result from various causes, including autoimmune inflammation, surgical removal or radioactive destruction, tumors, infections, glandular developmental abnormalities, hormone synthesis enzyme deficiencies, hormone gene mutations (variant hormones), receptor or post-receptor defects, and impaired hormone action.
Hormone Replacement Therapy
Hormone replacement therapy helps alleviate clinical manifestations associated with endocrine hypofunction. For example, insulin replacement is used for type 1 diabetes, and levothyroxine (L-T4) replacement is used for hypothyroidism. Attention is needed for the following aspects:
- Monitoring Efficacy: Evaluations are necessary to determine the effectiveness of treatments, such as monitoring serum TSH levels in L-T4 replacement therapy for primary hypothyroidism.
- Administering Based on Pharmacological Properties: Hormone administration methods depend on chemical properties and may include oral, intravenous, subcutaneous, or inhalation routes. It is important to mimic the physiological rhythm of hormone secretion as closely as possible.
- Adjusting Dosage Based on Physiological or Pathological States: Hormone requirements may vary with age, as well as internal and external environmental changes. For instance, doses of glucocorticoid replacement therapy often need to be significantly increased during stress.
- Considering Drug Interactions: Some medications, such as carbamazepine, can induce cytochrome P450 enzyme activity, accelerating glucocorticoid metabolism.
- Paying Attention to Adverse Reactions: For example, insulin injections may cause hypoglycemia and weight gain.
Pharmacological Therapy
The use of chemical agents to stimulate hormone secretion or enhance hormone action is effective for certain cases of endocrine hypofunction. Sulfonylureas or insulin sensitizers are options for treating type 2 diabetes. Certain congenital metabolic diseases result from insufficient synthesis of vitamins that act as cofactors for enzyme reactions or from reduced enzyme affinity for vitamin coenzymes due to defects. Supplementation with appropriate vitamins can help correct these metabolic abnormalities. For example, in hyperhomocysteinemia caused by cystathionine β-synthase deficiency, dietary restriction of methionine combined with high doses of vitamin B6 and folic acid can be beneficial.
Organ, Tissue, or Cell Transplantation
Transplantation of allogenic organs, tissues, or cells is utilized to restore endocrine gland function. Examples include transplantation of pancreas, pancreatic islets, or insulin-producing cells derived from human pluripotent stem cells to treat type 1 diabetes, and transplantation of parathyroid fragments into forearm muscle tissue to address primary hypoparathyroidism.
Etiological Treatment
Etiological treatments target the underlying mechanisms of the disease. These include utilizing genetically engineered enzymes to treat metabolic enzyme deficiencies, avoiding exposure to triggering substances (e.g., avoiding fava beans and drugs like aspirin and sulfonamides in glucose-6-phosphate dehydrogenase deficiency), and restricting dietary intake of phenylalanine in phenylketonuria to achieve effective prevention and management.