Study of the fluorescence properties of normal and neoplastic human cervical tissue

Fluorescence excitation-emission matrices (EEMs) were obtained in vitro for 18 cervical biopsies from 10 patients. At all excitation emission maxima, but especially at 330 nm excitation, 385 nm emission, the average normalized fluorescence intensity of histologically normal tissue is greater statistically than that of histologically abnormal tissue. A diagnostic algorithm based on the relative intensity at 330 nm excitation, 385 nm emission can differentiate histologically normal and abnormal biopsies with a higher sensitivity (89%), but a lower positive predictive value (67%) and specificity (44%) than colposcopy (78%, 88%, 89%, respectively). However, paired comparison of histologically normal and abnormal biopsies from the same patient results in a sensitivity of 75%, positive predictive value of 86% and specificity of 88% for spectroscopic identification of histologic abnormality similar to that of colposcopy. This pilot study indicates that fluorescence spectroscopy may be useful in differentiating normal and abnormal tissue; based on these results, a strategy for in vivo studies is discussed.