Could a simple blood test replace the annoying 24-Hour urine collection for tumor diagnosis?

This study looked at 116 people with small-intestine neuroendocrine tumors to see if a blood test or a shorter urine collection could replace the standard 24-hour urine test for diagnosis. The goal was to find a simpler, equally accurate way to measure a key tumor marker called 5HIAA. Results may lead to easier and faster testing for patients.