A 38 year old male consulted his local physician because he was experiencing strange episodes of skin flushing and sweating.The physician suspected a GI tumour,and ordered a CT scan,which disclosed a mass in the duodenum,and possible metastatic disease in the liver.The duodenal mass was biopsied,and is shown in the accompanying high power photomicrograph.An immunohistochemistry stain for chromogranin is shown on the right.Which one of the following is the best diagnosis?

Question

Quizplus · Accepted Answer

The islands of endocrinoid cells (compared to the appearance of the Islets of Langerhans)are typical of carcinoiDAlthough small cell carcinoma is related,it often is much more aggressive,and more atypical.The tumour cells produce serotonin,which accounts for the patient's symptoms.Serotonin is normally degraded in the liver,so metastatic disease is often necessary for the liver to be overwhelmed with the amount of serotonin it is required to process,before symptoms appear.

A 38 Year Old Male Consulted His Local Physician Because