Hydroxyindole-Producing Tumors of the Pancreas

Four patients had pancreatic tumors and elevated urinary 5-hydroxyindoleacetic acid. Three tumors were histologically identical to carcinoid or islet cell tumors; the other was anaplastic and suggested oat cell carcinoma. Two patients had severe diarrhea, and one had blotchy cyanosis of the extremities. A third showed hyperchlorhydria. A left upper quadrant systolic bruit was heard in the three patients with the better-differentiated tumors; these three patients have survived 2 to 6 years after the onset of symptoms, two with proved metastasis. The patient with the anaplastic tumor died 13 months after onset of the disease. Embryological and clinical evidences are reviewed that indicate the close interrelationship of the argentaffin system and pancreatic islets. It is suggested that the pancreaticislets are the source of serotonin-producing pancreatic neoplasms, and the term carcinoid-islet cell tumor (23) is proposed for these lesions. It is also proposed that the oat cell tumor originates from the pancreatic islets.