Carcinoid Syndrome

Key Points
Grouping of symptoms which are associated with the presence of carcinoid tumors
Appearance indicates mestastasis of a malignant tumor
Cutaneous appearance consists of flushing, a temporary and transient dilation of blood vessels
Dermatitis may be present in some cases

Carcinoid syndrome is a very serious grouping of symptoms which indicates the presence of a malignant carcinoid tumor, which may have metastasized. In addition to symptoms such as diarrhea, abdominal pain, heart palpitations, low blood pressure, and wheezing, a cutaneous presentation known as flushing occurs in approximately 75% of affected persons. Flushing involves the temporary and transient dilation of blood vessels in the head, face, neck or trunk, can last from minutes to several hours in late stage cases, and may sometimes be mottled, with occasional swelling. Persistent flushing can lead to permanent skin changes, including persistent redness and dilated blood vessels. Uncommonly, Dermatitis may occur in affected areas which are exposed to sunlight.

The cause of Carcinoid Syndrome is the presence of a carcinoid tumor, usually originating in the gastrointestinal system. Symptoms generally develop as the tumor mestastasizes to the liver, causing a buildup of certain substances in the bloodstream due to chemicals produced by the tumor.

Differential Diagnosis (Other conditions with similar appearance)

Anaphylaxis
Pheochromocytoma
Mastocytosis
Tumor Lysis Syndrome
Angioedema
Urticaria
Pellagra

Diagnosis
Key Points
Diagnosis based cutaneous appearance in conjunction with other symptoms
Testing of the chemical levels in the urine confirm diagnosis
Other testing involving the tracking of associated tumor growth will be performed

Carcinoid Syndrome is usually diagnosed by the appearance of cutaneous symptoms in conjunction with other symptoms, including diarrhea, wheezing, and liver enlargement. Testing for the chemicals which carcinoid tumors secrete is done to confirm diagnosis. Additional testing to assess the attendant tumor will be performed as well.

Treatment
Primary treatment goal is removal of the associated carcinoid tumor
If complete removal is not possible, a partial removal can alleviate symptoms
Other treatments are used to treat tumors which have spread to other organs

The best treatment for Carcinoid Syndrome is removal of the associated carcinoid tumor, which results in a permanent cure. If complete removal is not possible, portions of the tumor can be removed via surgical debulking to alleviate symptoms. Other surgical treatments can be used to treat tumors which spread to the liver and other organs. In the case of advanced tumors where surgery is not an option, several treatments have proven effective in stopping and even reversing tumor growth. These treatments include chemotherapy, the use of drugs which block the chemicals produced by carcinoid tumors, and administration of interferon, an immune modulator which suppresses and reverses tumor growth.