Small cell carcinoma with two paraendocrine syndromes.

Simultaneous elevated levels of ectopic arginine vasopressin (AVP) and ectopic adrenocorticotropin (ACTH) were found in a patient with small cell carcinoma (SCC). The finding of one of these paraendocrine syndromes at the time of diagnosis is common; however, the simultaneous presence of both syndromes has been reported in the literature only on four occasions in the past 25 years. This is the only report in which elevated plasma levels of both hormones are documented in a patient who simultaneously fulfills the criteria for the syndrome associated with each ectopically produced peptide. In the English-language literature, this is the first case that demonstrates by immunohistochemical staining the presence of both of these hormones in the patient's neoplasm. In addition to the use of radiographs, the presence of paraendocrine disorders can provide a method of monitoring the patient's response to therapy. The levels of ACTH and AVP were assayed during this patient's course and correlated with disease refractory to therapy, resulting in poor survival.