Carcinoid Syndrome

This clinical condition describes a pattern of signs and symptoms that can develop when neuroendocrine tumors, typically originating in the digestive tract or lungs, secrete substances such as serotonin into the systemic circulation. These bioactive chemicals travel through the blood and may affect various organ systems because they are not neutralized before reaching the rest of the body.

The syndrome is often observed in cases where tumors have reached the liver, allowing secreted hormones to bypass the organ's typical metabolic filtration process. The term remains the current medical designation for this specific hormonal manifestation and is distinct from the primary tumor diagnosis itself.