title: Characterizing breast cancer tissues through the spectral correlation properties of polarized fluorescence.
abstract: We study the spectral correlation properties of the polarized fluorescence spectra of normal and cancerous human breast tissues, corresponding to patients belonging to diverse age groups and socioeconomic backgrounds. The emission range in the visible wavelength regime of 500 to 700 nm is analyzed, with the excitation wavelength at 488 nm, where flavin is one of the active fluorophores. The correlation matrices for parallel and perpendicularly polarized fluorescence spectra reveal correlated domains, differing significantly in normal and cancerous tissues. These domains can be ascribed to different fluorophores and absorbers in the tissue medium. The spectral fluctuations in the perpendicular component of the cancerous tissue clearly reveal randomization not present in the normal channel. Random matrix-based predictions for the spectral correlations match quite well with the observed behavior. The eigenvectors of the correlation matrices corresponding to large eigenvalues clearly separate out different tissue types and identify the dominant wavelengths, which are active in cancerous tissues.
authors.affiliation: Gujarat University, C. U. Shah Science College, Ahmedabad, 380 009, India.
authors.forename: Anita H
authors.initials: AH
authors.lastname: Gharekhan
authors.forename: Siddharth
authors.initials: S
authors.lastname: Arora
authors.forename: K B K
authors.initials: KB
authors.lastname: Mayya
authors.forename: Prasanta K
authors.initials: PK
authors.lastname: Panigrahi
authors.forename: M B
authors.initials: MB
authors.lastname: Sureshkumar
authors.forename: Asima
authors.initials: A
authors.lastname: Pradhan
mesh_terms: D000465:Algorithms; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000503:physiopathology*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013223:Statistics as Topic