S3570 Incidentally Discovered Multifocal Subclinical Well-Differentiated Neuroendocrine Tumors in the Jejunum Resection of the Bowel for Symptoms of Obstruction

Abstract

INTRODUCTION: Jejuno-ileal well-differentiated neuroendocrine tumors (WDNET) usually have a relatively high rate of transmural invasion, numerous regional metastases, and advanced stage at the time of presentation. Here we report a rare case of multiple subclinical WDNET that were incidentally discovered after resection of the bowel for an incarcerated intraabdominal hernia. CASE DESCRIPTION/METHODS: The patient is a 69-year-old lady with a longstanding history of uncontrolled diabetes and coronary atherosclerosis who was admitted for cardiac catheterization. However, in the hospital, she complained of abdominal pain, nausea, and vomiting and was diagnosed with incarcerated small bowel hernia with closed-loop obstruction, for which, she underwent segmental resection of the jejunum and hernia repair. Grossly, besides the 35.0 cm of dark-red dull infarcted mucosa, the surgically removed segment of jejunum had up to 37.0 cm of unremarkable velvety tan-pink mucosa, in which there were nine barely visible plaque-like pale-pink lesions ranging from 0.1 × 0.1 × 0.1 cm up to 0.6 × 0.5 × 0.3 cm. The lesions had a white-yellow cut surface. Upon microscopic examination, nests and islets of monomorphic tumor cells with up to 1.6 mitoses per 2 mm2 were noted. The tumor cells expressed neuroendocrine immunohistochemical markers and had a low proliferative index (Ki-67 1%). Tumors were limited to mucosa and submucosa with no muscular propria invasion or lymph node metastases. DISCUSSION: Although rarely, Jejunal WDNET can be incidentally discovered at the early subclinical stage.