Raman spectroscopy for neoplastic tissue differentiation: a pilot study.

BACKGROUND Several changes occur during the transformation of normal tissue to neoplastic tissue. Such changes in molecular composition can be detected by Raman spectroscopy. Raman spectroscopy is a nondestructive method of measuring these changes, which suggests the possibility of real-time diagnosis during medical procedures. METHODS This study seeks to evaluate the ability of Raman spectra to distinguish tissues. The Raman signatures of normal kidney, lung, and liver tissue samples from pigs and rats were characterized in vitro. Further, a human neuroblastoma and a hepatoblastoma, obtained at resection were also studied. RESULTS The Raman spectra of the animal samples of kidney, liver, and lung are distinctly different in the intensity distribution of the Raman peaks. Further, the spectra of a given organ from pigs and rats, although similar, were different enough to distinguish between the 2 animals. In the patient tissues, the Raman spectra of normal liver, viable tumor, and fibrotic hepatoblastoma were very different. Fibrotic tissue showed a greater concentration of carotenoids, whereas viable tissue was rich in proteins and nucleic acids. The normal tissue showed both components. Similar differences were also seen in the neuroblastoma tissue. CONCLUSIONS The results of this study show the potential use of Raman spectroscopy in clinical diagnosis.