title: In vivo Raman spectroscopy of human uterine cervix: exploring the utility of vagina as an internal control.
abstract: In vivo Raman spectroscopy is being projected as a new, noninvasive method for cervical cancer diagnosis. In most of the reported studies, normal areas in the cancerous cervix were used as control. However, in the Indian subcontinent, the majority of cervical cancers are detected at advanced stages, leaving no normal sites for acquiring control spectra. Moreover, vagina and ectocervix are reported to have similar biochemical composition. Thus, in the present study, we have evaluated the feasibility of classifying normal and cancerous conditions in the Indian population and we have also explored the utility of the vagina as an internal control. A total of 228 normal and 181 tumor in vivo Raman spectra were acquired from 93 subjects under clinical supervision. The spectral features in normal conditions suggest the presence of collagen, while DNA and noncollagenous proteins were abundant in tumors. Principal-component linear discriminant analysis (PC-LDA) yielded 97% classification efficiency between normal and tumor groups. An analysis of a normal cervix and vaginal controls of cancerous and noncancerous subjects suggests similar spectral features between these groups. PC-LDA of tumor, normal cervix, and vaginal controls further support the utility of the vagina as an internal control. Overall, findings of the study corroborate with earlier studies and facilitate objective, noninvasive, and rapid Raman spectroscopic-based screening/diagnosis of cervical cancers.
authors.affiliation: Chilakapati Lab, ACTREC, Kharghar, Navi-Mumbai 410210, India.
authors.forename: Rubina
authors.initials: R
authors.lastname: Shaikh
authors.affiliation: Tata Memorial Center, Radiation Oncology, ACTREC, Kharghar, Navi Mumbai 410210, India.
authors.forename: Tapas Kumar
authors.initials: TK
authors.lastname: Dora
authors.affiliation: Tata Memorial Center, Radiation Oncology, ACTREC, Kharghar, Navi Mumbai 410210, India.
authors.forename: Supriya
authors.initials: S
authors.lastname: Chopra
authors.affiliation: Tata Memorial Hospital, Gynecology Oncology, Parel, Mumbai 400012, India.
authors.forename: Amita
authors.initials: A
authors.lastname: Maheshwari
authors.affiliation: Tata Memorial Hospital, Department of Pathology, Parel, Mumbai 400012, India.
authors.forename: Deodhar
authors.initials: D
authors.lastname: Kedar K
authors.affiliation: Tata Memorial Hospital, Department of Pathology, Parel, Mumbai 400012, India.
authors.forename: Rekhi
authors.initials: R
authors.lastname: Bharat
authors.affiliation: Chilakapati Lab, ACTREC, Kharghar, Navi-Mumbai 410210, India.
authors.forename: C Murali
authors.initials: CM
authors.lastname: Krishna
mesh_terms: D000465:Algorithms; D014408:Biomarkers, Tumor / Q000032:analysis*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013059:Spectrum Analysis, Raman / Q000379:methods*; D002583:Uterine Cervical Neoplasms / Q000737:chemistry* / Q000175:diagnosis*; D014621:Vagina / Q000737:chemistry*
chemical_list: D014408:Biomarkers, Tumor