Detecting Cervical Dysplasia in Minority Populations with Raman Spectroscopy

Cervical cancer is the second most common malignancy among women worldwide. A "See and Treat" protocol with adequate sensitivity and specificity would significantly improve this disease's management in low-resource settings.

Over the past few years, our laboratories have developed a probe-based instrument to acquire Raman spectra from the cervix (see Figure).  Raman spectroscopy uses light to measure the vibrational and rotational properties of bonds found in a variety of biomolecules.  It is a molecular specific technique that can provide detailed information about the biochemical composition of a tissue sample.  Patients undergoing a Pap smear or colposcopy-guided biopsy are recruited to this study under informed consent.  For the Pap smear patients, the sterilized probe is placed directly onto the cervix in various locations for 2-3 seconds.  For the colposcopy-guided biopsy patients, the probe is placed in one normal area and any area(s) the doctor decides to biopsy.  We have acquired Raman spectra from the cervix and developed a sophisticated algorithm to classify tissue as normal (benign or inflammatory), metaplasia, low-grade, or high-grade dysplasia.

Previous results from a Caucasian population show that our tool works with a sensitivity of 98% and a specificity of 96%, with high-grade spectra classifying correctly 95% of the time and low-grade data classifying correctly 74% of the time.  Preliminary data analysis on a more diverse patient population shows more varied results, due to race/ethnicity and differing socioeconomic status.  Parsing the data based on these backgrounds leads to sensitivity, specificity, and classification rates closer to that found in a more homogenous Caucasian population.

The results of using this non-invasive tool that can be used directly on patients from varying socioeconomic and ethnic/racial backgrounds show its benefit in any place where professional care is difficult to achieve.
Key words: see and treat, optical diagnosis