Abstract

Breast cancer has one of the highest incidence and mortality rates in the U.S. X-ray mammography is one of the most common tools to diagnose breast cancer. Because of the effects of ionizing radiation and difficulty in differentiating benign from malignant tumors, there is a need for new methods. Fluorescence spectroscopy is a possible modality. We tested over 40 samples of cancerous and noncancerous breast tissues by means of UV-fluorescence spectroscopy. Each sample was excited in the UV, and the ratio of fluorescence intensities at different emission wavelengths were calculated. The ratio of intensities at different wavelengths allowed us to differentiate between malignant tumors and benign tumors and between tumors and normal tissues. The average ratio for 19 malignant samples was 15.7, and for 20 benign tissues and (fibroadenoma) tumors it was 4.7. Pathological diagnosis of each sample was known before the experiment was performed, and the results were used to build up a ratio histogram. Later blind samples were tested, and the results were in 99% agreement with the diagnoses made by pathologists. A spectral study indicates that tryptophan, tyrosine, and NADPH may be among the fluorophors causing the fingerprint of cancer.

© 1990 Optical Society of America