Unusually aggressive type 1 gastric carcinoid: a case report with a review of the literature.

Gastric carcinoids are rare tumors of the stomach. Gastric carcinoid type 1 is associated with chronic atrophic gastritis, and because of a low metastatic potential, is the most benign type. Death from metastatic disease has been reported in only three patients in a review including 724 cases. The present report refers to a 60-year-old man who was affected by type 2 diabetes mellitus and pernicious anemia and died from metastatic gastric carcinoid type 1. In 1998, a well-differentiated 1.2 cm gastric neuroendocrine tumor, immunoreactive for chromogranin A, with a Ki-67 index less than 2% and with infiltration to the submucosal layer was diagnosed and enucleated. In 2002, a new well-differentiated gastric endocrine tumor 6 mm in size with a Ki-67 of approximately 2% was detected, and endoscopic ultrasound confirmed it to be limited to the submucosal layer. The patient refused antrectomy and started long-acting somatostatin analog (lanreotide) in 2005 when the Ki-67 index was 7%, but he stopped the treatment after 4 months. In 2007, despite previous endoscopic stability, endoscopic ultrasound showed an infiltrating gastric lesion of 7 cm. At surgery, the disease appeared to be extended to the liver and to the peritoneum (well-differentiated endocrine carcinoma, Ki-67 40%) with both hepatic and massive peritoneal metastases. A regimen of somatostatin analog was soon restarted; however, the disease continued to spread, and the patient died 6 months later. Overall, despite their generally benign course, type 1 gastric carcinoids may have malignant potential, a finding that should be considered when planning the medical workup of these patients.