A pilot study of fluorescence diagnosis of basal cell carcinoma using a digital flash light-based imaging system

Background/purpose: Fluorescence diagnosis (FD) is a promising method for the non-invasive detection of tumor boundaries. We aimed to investigate the clinical utility of a flash light-based fluorescence imaging system. Methods: Sixteen patients with basal cell carcinomas were included in this pilot study. FD was performed using a 20% 5-aminolevulinic acid (ALA) cream. The FD tumor area was determined 3 h after the ALA application using a digital flash light-based fluorescence imaging system and an image analysis system. The tumor area was also assessed by means of the clinical diagnosis (CD) based on the normal colored picture. The tumors were excised following the FD procedure, but according to the clinically diagnosed lesional area. Results: Though there was a very strong correlation between the tumor areas assessed by FD and CD, the mean tumor area that was visualized by FD was significantly smaller than the tumor area determined by CD. The mean +/- SD FD/CD ratio was 0.78 +/- 0.11 in total. In 81.3% of cases, complete tumor excision was achieved. Conclusion: This pilot study indicates that the FD technology may be less sensitive than CD, and refinements of the technique along with larger systematic trials on the sensitivity and specificity of FD are required.