Carcinoid syndrome from gastrointestinal carcinoids without liver metastasis.

Although patients with bronchial and ovarian carcinoid tumors can develop the carcinoid syndrome (diarrhea and/or flushing) in the absence of hepatic metastasis, it is believed that development of the carcinoid syndrome in patients with carcinoid tumors of gastrointestinal origin occurs only after the patient has hepatic metastasis. This is explained by hepatic inactivation of most of the serotonin in the portal circulation or by the fact that hepatic metastases are larger than the primary tumor in the gastrointestinal tract. Three patients with ileal and jejunal carcinoid tumors who developed the carcinoid syndrome without obvious hepatic metastasis are described. Two of the patients had intra-abdominal, but extrahepatic, metastasis that probably drained directly into the systemic circulation. The third patient had an ileal carcinoid with clinical involvement limited to adjacent mesenteric lymph nodes. Following resection of her tumor, her urinary 5-HIAA excretion and platelet serotonin level returned to normal, and her attacks of carcinoid flushing virtually ceased. She has occasional spells of "blushing" that are thought to be benign; however, further close follow-up study will be needed to be certain that she is free of disease. It is suggested that each patient with the carcinoid syndrome be evaluated with CT and technetium-99 pertechnetate liver scans. If there is no liver involvement detected with these studies, one should consider hepatic arteriogram or laparotomy to determine if the patient's tumor might be totally resectable.