Table 2.

The characteristics of flushing in neuroendocrine tumors.

Syndrome	Characteristics
Carcinoid syndrome	Midgut: rapid cyanotic flush that last for less than a minute and commonly associated with a mild burning sensation Foregut: pruritic reddish-brown with variegated margination or bright red and confluent, with wheals over the entire body, and associated with chemosis, facial edema, or hypotension. Those with bronchoconstriction are usually bright red and confluent, and associated with chemosis, facial edema, or hypotension. Accompanying symptoms are common, including diarrhea, dyspnea, abdominal pain or wheezing. Chronic flushing may lead to thick skin changes with venous telangiectasia and bluish coloration of the face or upper torso.
Pancreatic Neuroendocrine Tumors	Rapid cyanotic flush that last for less than a minute and commonly associated with a mild burning sensation Pruritic reddish-brown with variegated margination or bright red and confluent, with wheals over the entire body, and associated with chemosis, facial edema, or hypotension.
Endogenous Cushing syndrome	Flushing is rarely a presenting complaint and is usually subjective. Facial plethora is consistent and unlike flushing rarely episodic; it is also decreased after surgery, due to reduction of blood volume perfusion.