Endocrine Paraneoplastic Syndromes: A Review

Abstract

It is important for the endocrinologist and oncologist to recognize these paraneoplastic endocrine syndromes since this may help in defining the cancer type and hence lead to the appropriate management. In addition, these syndromes are a major cause of morbidity and mortality. Moreover, AbstractParaneoplastic endocrine syndromes result from ectopic production of hormones by different tumors. Hypercalcemia of malignancy is the most common, mostly caused by ectopic parathyroid hormone related peptide (PTHrP) production which increases bone resorption. Other causes include the rare ectopic parathyroid hormone (PTH) production, ectopic production of 1, 25-(OH)2 vitamin D by the tumor and its adjacent macrophages and bone metastasis which by itself in addition to the local production of PTHrP at the level of the bone lead to bone resorption and thus hypercalcemia. Treatment includes extracellular fluid volume repletion, bisphosphonates or denosumab and calcitonin. Ectopic Cushing's syndrome caused by ectopic ACTH production results in hypokalemia, proximal muscle weakness, easy bruisability, hypertension, diabetes and psychiatric abnormalities including depression and mood disorders. Different diagnostic measures help to differentiate Cushing's disease from ectopic Cushing's syndrome. Treatment includes surgical resection of tumor and medical therapy to suppress excess cortisol production. Ectopic secretion of ADH has been associated with different tumor types. The best treatment options include removal of the underlying tumor, chemotherapy, or radiotherapy in addition to free water restriction, demeclocycline and vaptans. Ectopic growth hormone releasing hormone secretion has been identified with carcinoids, phechromocytoma and other tumors. Surgery is the mainstay of therapy with systemic therapy used in metastatic disease. Other rare ectopic hormone syndromes have also been identified including ectopic prolactin, ectopic erythropoietin, and thrombopoetin in addition to others. Keywords 2/12paraneoplastic endocrine syndromes may be the first presenting feature of malignancy [2,3]. This paper provides an overview on the common PNES, their prevalence, diagnosis, prognosis and response to treatment (Table 1). Methodology of Literature SearchEligible studies were identified by a search, from year 1920 up till February 2014, in Medline, PUBMED and EMBASE using a refined search strategy with several terms used including "endocrine paraneoplastic syndromes", "ectopic hormones", "humoral hypercalcemia of malignancy", "ectopic parathyroid hormone related peptide", "ectopic ACTH", "ectopic Cushing syndrome", "ectopic antidiuretic hormone", "syndrome of inappropriate ADH", "ectopic growth hormone releasing hormone", "ectopic growth hormone", "ectopic prolactin", "ectopic thyroid stimulating hormone" in addition to several others. In addition, searches of personal collections and the reference lists of eligible studies were identified with their full text papers being retrieved. A-Hypercalcemia of MalignancyHistorical Perspec...

Endocrine Paraneoplastic Syndromes in Lung Cancer: A Respiratory Physician’s Perspective

“…Excision of the tumour is the best treatment [67]. Unlike other organ NETs (even with significant liver metastasis), carcinoid crisis risk with lung NETs is low, and hence prophylactic administration of octreotide before any tumour manipulation (biopsy or resection) is not recommended [62].…”

Endocrine Paraneoplastic Syndromes: A Review

“…It also enhances the production of RANK ligand (RANKL) by osteoblastic stromal cells, which acts as a powerful inducer of osteoclast formation and differentiation. [17][18][19][20] PTHrP also inhibits the production of osteoprotegerin (OPG). OPG is a secreted member of the tumor necrosis factor (TNF) receptor family that is produced by osteoblastic stromal cells, and is capable of inhibiting osteoclast formation.…”