WHO Grade 2 Neuroendocrine Tumor in a 15-Year-Old Male: A Case Report and Literature Review.

Neuroendocrine tumors, distinguished from adenocarcinomas by their neuroendocrine differentiation, are the most common pediatric epithelial malignancy that most often occurs in the appendix. In 2010, the WHO classified neuroendocrine neoplasms into three grades based on morphology, mitotic count, and Ki67 proliferation index. A 15-year-old male with a history of anemia and failure to thrive was diagnosed with a well-differentiated neuroendocrine tumor in the jejunum that invaded into the subserosal soft tissue and metastasized to four lymph nodes. Pediatric neuroendocrine tumors frequently arise within hereditary tumor syndromes with pancreatic neuroendocrine tumors being the most common. Several studies also indicate an elevated risk of small intestinal neuroendocrine tumors in which children born to a parent with a history of neuroendocrine tumors in the small intestine have a significant increased risk of developing one.