Distinct infrared spectroscopic patterns of human basal cell carcinoma of the skin.

Infrared spectroscopy combined with high pressure (pressure-tuning infrared spectroscopy) was applied to the study of paired sections of basal cell carcinomas (BCC) and normal skin from ten patients. Atmospheric pressure IR spectra from BCC were dramatically different from those from the corresponding normal skin. Compared to their normal controls, BCCs displayed increased hydrogen bonding of the phosphodiester group of nucleic acids, decreased hydrogen bonding of the C--OH groups of proteins, increased intensity of the band at 972 cm-1, a decreased intensity ratio between the CH3 stretching and CH2 stretching bands, and accumulation of unidentified carbohydrates. Some of these changes are shared by all human epithelial malignancies studied to date, while some others appear as yet unique to basal cell carcinoma. The diagnostic value of infrared spectroscopy in BCC remains to be determined.