What paraneoplastic syndrome is associated with small cell lung carcinoma?

Small cell lung carcinoma (SCLC) is known to be associated with various paraneoplastic syndromes due to the production of hormones or hormone-like substances by the tumor. One of the classic paraneoplastic syndromes linked to SCLC is the inappropriate secretion of antidiuretic hormone (SIADH).

Patients with SCLC may develop hyponatremia and other symptoms related to fluid overload due to the excess release of vasopressin (ADH), leading to water retention and dilutional hyponatremia. This occurs because the tumor cells can produce ADH ectopically, independent of the normal regulation by the hypothalamus. The clinical manifestation of this syndrome may include symptoms such as confusion, seizures, or other neurological changes as a consequence of low serum sodium levels.

Other options are associated with different types of tumors or mechanisms. For example, hypercalcemia due to parathyroid hormone-related peptide (PTHrP) is more commonly associated with squamous cell lung carcinoma, not SCLC. Stimulation of thyroid hormone release is generally associated with other malignancies, such as thyroid cancer. The secretion of ectopic insulin is not typically related to SCLC, as this type of secretion is more characteristic of other