Malignant enterochromaffinlike cell carcinoid of the gastric stump: an ultrastructural study.

A metastasizing carcinoid of the gastric stump found 25 years after Billroth II gastric resection for duodenal ulcer is described. Electron microscopy and optical endocrine cell staining proved the tumor to be composed of enterochromaffinlike (ECL) cells. This unusual combination further shows that, at variance with most of these tumors, ECL cell carcinoids may develop also in a condition excluding a trophic effect of gastrin. This case emphasizes the malignant behavior of gastrin-independent ECL cell tumors.