Eligibility criteria: Gastrointestinal disease or clinical symptoms related to colorectal cancer risk submitted to endoscopy. Exclusion criteria consisted of age younger than 18 years, history of psychiatric illness, and preoperative radiotherapy.
Outcome: investigated the possible role of the native fluorescence of blood plasma in the management of colorectal cancer (CRC) and its feasibility as a new tumor marker. Sample of blood was collected from asymptomatic blood donors and from CRC patients. The native fluorescence of blood plasma was measured using a conventional spectrofluorimeter.