Paraneoplastic endocrine syndromes: a contemporary overview.

Endocrine paraneoplastic syndromes (ePNS) are caused by malignant cells that induce hormonal alterations unrelated to the tissue of origin of the neoplasm. The aim of this manuscript is to review the pathophysiology, diagnosis, and treatment of endocrine paraneoplastic syndromes (ePNS). We searched the PubMed/Medline, Embase, and Scielo databases, including 96 articles. The pathogenesis of ePNS involves mutations that activate hormonal genes. Hypercalcemia, the most common ePNS, is marker of poor prognosis in most cases. The syndrome of inappropriate antidiuresis causes euvolemic hyponatremia. Ectopic Cushing's syndrome is commonly associated with lung cancer. Paraneoplastic acromegaly is very rare and is associated with pancreatic and lung tumors. Paraneoplastic hypoglycemia usually requires surgical treatment. Other endocrine paraneoplastic syndromes include ectopic secretion of hormones such as calcitonin, renin, vasoactive intestinal polypeptide, fibroblast growth factor 23, paraneoplastic autoimmune hypophysitis, and others. In addition to the local manifestations and metastasis of neoplasms, some secrete bioactive substances causing PNS. Recognizing and treating PNS early improves clinical outcomes. Larger-scale studies and clinical trials are needed to enhance their management and prognosis.