Porphyrin fluorescence of experimentally produced squamous cell carcinoma

Abstract

ULCERATED squamous cell carcinomas of the human skin frequently show a red fluorescence when examined under ultra-violet radiation1-3. This red fluorescence is usually restricted to small areas of the necrotic surface. Hitherto the substance or substances responsible for this phenomena have not been identified. This is probably due to the fact that very small amounts of material are available for study in any single case. Recently, Ghadially4 observed that experimentally produced squamous cell carcinomas of the skin of many animals show a similar red fluorescence. It seemed to us that by pooling material from a number of tumours, sufficient might be obtained for a chemical analysis. Six rabbits with large ulcerated carcinomas produced by repeated painting of the skin with a 2 per cent solution w/w of 9 : 10 dimethyl 1 : 2 benzanthracene in a mixture of equal parts of lanolin and paraffin were available for study. After many attempts, we were ultimately able to collect one large (5 gm.) pooled sample for analysis. Another large sample was obtained from a single rabbit which died as a result of a very large fungating carcinoma of the ear. Here about 5 gm. of red fluorescent debris had collected on the carcinoma and within the ear over a prolonged period of time. The results obtained in each case were essentially similar. © 1960 Nature Publishing Group.