Cutaneous manifestations of carcinoid tumor and syndrome

Carcinoid syndrome refers to the signs and symptoms a patient experiences secondary to a carcinoid tumor or another well-differentiated neuroendocrine tumor, which secretes serotonin and other peptides that enter the bloodstream; only 10% of patients with carcinoid tumors experience carcinoid syndrome. Common findings include facial flushing, tachycardia, and shortness of breath. Carcinoid tumors usually originate in the gastrointestinal tract. They are slow growing but can metastasize to the liver, lymph nodes, and elsewhere. Primary or metastatic cutaneous carcinoid tumors present as pink, fast-growing dermal or subcutaneous nodules. The diagnostic workup includes a thorough history and physical examination of the entire body, including a urinary 24-hour 5-hydroxyindoleacetic acid and serum chromogranin A tests. Management of carcinoid syndrome initially includes the use of somatostatin analogs, diet, medication regulation, and clinical monitoring. More aggressive treatment, such as peptide receptor radionuclide therapy or everolimus, a mechanistic target of rapamycin (mTOR), may be required.