Association between high serum carcinoembryonic antigen and clinical state of male anorexia nervosa: A case report.

Anorexia nervosa (AN) is a complex psychiatric disorder, which is not yet fully understood. Several studies reported that AN was associated with disruption of cytokine network. Carcinoembryonic antigen (CEA) is a glycoprotein related to its network, used as a tumor marker of adenocarcinoma, and suggested to stimulate monocytes and macrophages to release proinflammatory cytokines. Here, we report a 41-year-old male suffering from AN who was suspected of having a malignant tumor due to markedly elevated serum CEA levels. However, on further examinations, he was discovered to have no malignant tumors, and, interestingly, his CEA levels actually decreased as his clinical state of AN improved. Furthermore, it was found that his CEA levels were elevated proportionally to his clinical state of AN and that his body mass index was significantly correlated with serum CEA levels. Therefore, it is suggested that inflammatory responses may be associated with the clinical state of AN.