Hepatic nodular regenerative hyperplasia in a patient with advanced carcinoid tumor.

Nodular regenerative hyperplasia (NRH) of the liver is a rare disease that is characterized by multiple regenerative nodules in the hepatic parenchyma that may lead to noncirrhotic portal hypertension. The exact pathogenesis of NRH has not been established, but it has been suggested that a primary vascular abnormality causing local ischemia may initiate the nodular transformation. It is also known that this condition is associated with autoimmune disease, hematological disease, and some chemotherapy agents in which vasculopathy is a prominent feature. The patients with NRH are usually asymptomatic unless they develop complications related to portal hypertension. We report a case of a middle-aged female patient with florid carcinoid syndrome, speculating that vasoactive hormones including serotonin secreted by the tumor caused intrahepatic microcirculatory disturbances that eventually induced NRH. This association has not been reported earlier.