Fluorescence photograph of stomach cancer tumors in Wistar rats: computerized analysis

Detection of cancer in early stages with hematoporphyrin derivatives (HpD) is highly limited by the low fluorescence quantum yield, the strong autofluorescent components of the tissue, and the low contrast between normal and tumoral tissue when fluorescent photographs are taken. A new computer analysis based on digital subtraction of photographs before and after the administration of HpD, allows a total autofluorescence extraction, resulting in a remarkable increase of contrast between tumors and normal tissue. Experiments, with this computerized imaging system in adenocarcinoma of the stomach in Wistar rats, confirms the reliability of this method.