Gastrointestinal carcinoids: the evolution of diagnostic strategies.
Carcinoid tumors are rare, often insidious neoplasms arising from neuroendocrine cells. The majority arise in the gastrointestinal system, and are often incidentally found during investigation, although some may present as an emergency bleed or perforation. The prosaic symptoms of flushing, diarrhea, and sweating are often overlooked; thus, the diagnosis is usually much delayed and the tumor is advanced at presentation. This diagnostic delay renders effective management difficult and adversely affects outcome. This overview provides a current assessment of the evolution of the diagnostic techniques available to establish an accurate biochemical (5-hydroxyindole-3-acetic acid and chromogranin A) and topographic diagnosis (octreoscan, radio-labeled metaidobenzylguanidine, computerized tomography, magnetic resonance imaging, positron emission tomography, enteroclysis, endoscopic ultrasound, enteroscopy, capsule endoscopy, and angiography) of carcinoid tumors. The utility and shortcomings of the respective modalities available are evaluated. Although considerable advances have been made in establishing the diagnosis of carcinoid tumors and in defining the topography of metastatic disease, the major limitation is the inability to establish an early and timely diagnosis before the advent of metastatic disease.
Modlin
Irvin M
IM
Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, USA. imodlin@optonline.net
Latich
Igor
I
Zikusoka
Michelle
M
Kidd
Mark
M
Eick
Geeta
G
Chan
Anthony K C
AK
D019797:3-Iodobenzylguanidine; D014408:Biomarkers, Tumor / Q000097:blood; D001859:Bone Neoplasms / Q000000981:diagnostic imaging; D001842:Bone and Bones / Q000000981:diagnostic imaging; D053704:Capsule Endoscopy; D002276:Carcinoid Tumor / Q000175:diagnosis* / Q000556:secondary; D053379:Chromogranin A / Q000097:blood; D019160:Endosonography; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000097:blood; D008279:Magnetic Resonance Imaging; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D013004:Somatostatin / Q000031:analogs & derivatives
D014408:Biomarkers, Tumor; D053379:Chromogranin A; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine; D013004:Somatostatin; D006897:Hydroxyindoleacetic Acid; C081788:pentetreotide