One of the standard tests to try to diagnose carcinoid and neuroendocrine tumors has been the 5-HIAA test – which required a 24-hour sample of urine. This was often messy, inconvenient, embarrassing, and consequently sometimes inaccurate.
The term 5-HIAA stands for 5-Hydroxyindoleacetic acid which is a main metabolite of serotonin – and which is typically found in large quantities in those with tumors such as carcinoid.
Researchers from University of Iowa, Eastern Virginia Medical School, and Louisiana State University have developed a blood test that can establish 5-HIAA plasma levels. Further, they found that this fasting 5-HIAA blood level is proportionate to the 24-hour urinary levels – giving similar useful clinical information without the hassles of the urine test.
Dale O’Brien, MD