IR spectra of breast tumor cell lines and breast tumor tissues have been measured. IR measurements of tumor cells revealed that approximately 15 cells are necessary to obtain spectra of good signal-to-noise ratio using an IR microspectrometer equipped with a conventional IR thermal source. Comparative studies of human breast tumor cell line suspensions demonstrated that MCF-7 cells and drug-resistant NCI/ADR cells can be differentiated based on their IR spectra. The most striking differences between MCF-7 and NCI/ADR were found in features assigned to CH₂ and CH₃ stretching vibrations of lipid acyl chains and PO₂ stretching vibrations of nucleic acids. To assess the potential of IR spectroscopy for the diagnosis of breast tumor tissues, thin sections of tissue were mapped by FTIR microspectroscopy. The spectra of these maps were analyzed using functional group mapping techniques and cluster analysis, and the output values of the different approaches were then reassembled into IR images of the tissue. A comparison of the IR images with the standard light microscopic images of the corresponding areas suggested that: (i) chemical mapping based on single band intensities is an easy way to detect microscopic fat droplets within tissue; (ii) the comparison of IR images based on band intensities at 1054 and 1339 cm^-1 provides information on tissue areas containing tumor cells; (iii) cluster analysis of the spectra is superior to the single band approach and more appropriate for differentiation between tissue types.

Date Published: 24 April 1998
PDF: 11 pages
Proc. SPIE 3257, Infrared Spectroscopy: New Tool in Medicine, (24 April 1998); doi: 10.1117/12.306082

Published in SPIE Proceedings Vol. 3257:
Infrared Spectroscopy: New Tool in Medicine
Henry H. Mantsch; Michael Jackson, Editor(s)