Neuroendocrine neoplasms of the gastrointestinal tract: classification, pathologic basis, and imaging features.
Many radiologists are unfamiliar with the recently developed World Health Organization classification scheme for neuroendocrine tumors. According to this classification scheme, neuroendocrine tumors are divided into well-differentiated endocrine tumors (carcinoids), well-differentiated endocrine carcinomas (malignant carcinoids), and poorly differentiated endocrine carcinomas on the basis of their location, histologic features, and biologic behavior. Most neuroendocrine tumors have nonspecific imaging characteristics. However, they sometimes have peculiar clinical manifestations and radiologic features, on the basis of which radiologists may infer the specific diagnosis. Neuroendocrine tumors of the gastrointestinal tract originate from the cells derived from the embryonic neural crest, neuroectoderm, and endoderm. They usually produce bioactive substances and show immunoreactivity to neuroendocrine markers. Although neuroendocrine tumors are uncommon, they should be considered in developing the differential diagnosis for gastrointestinal tumors in patients with a typical syndrome or when the tumors have characteristic imaging features.
Chang
Samuel
S
Department of Radiology and Center for Imaging Science, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710, South Korea.
Choi
Dongil
D
Lee
Soon Jin
SJ
Lee
Won Jae
WJ
Park
Mi-hyun
MH
Kim
Sang Won
SW
Lee
Da Keun
DK
Jang
Kee-Taek
KT
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D018278:Carcinoma, Neuroendocrine / Q000145:classification* / Q000175:diagnosis* / Q000473:pathology; D002454:Cell Differentiation; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000145:classification* / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged
D014408:Biomarkers, Tumor