Fluorescence study of normal, benign, and malignant human breast tissues

Fluorescence properties of flavins in normal, benign and malignant human breast tissues have been investigated between 500-700 nm using 488 nm excitation of an Ar-ion laser. The combination of fluorescence anisotropy and spectral profiles can distinguish normal, benign and malignant from one another. The fluorescence spectra may be characterized by two major bands with the width of the band at 580nm being the distinguishing parameter. The polarization study of human breast tissues shows higher anisotropy for the tumor tissues compared to their normal counterparts. The effects of multiple scattering on depolarization of fluorescence is confirmed by polarization measurements on thin tissue sections which show higher anisotropy values compared to the thick samples. An important observation is the increase in the difference of anisotropy values between some of the normal and malignant tumor samples while going form thick to thin tissues.