Quantification of confocal fluorescence microscopy for the detection of cervical intraepithelial neoplasia.
BACKGROUND
Cervical cancer remains a major health problem, especially in developing countries. Colposcopic examination is used to detect high-grade lesions in patients with a history of abnormal pap smears. New technologies are needed to improve the sensitivity and specificity of this technique. We propose to test the potential of fluorescence confocal microscopy to identify high-grade lesions.


METHODS
We examined the quantification of ex vivo confocal fluorescence microscopy to differentiate among normal cervical tissue, low-grade Cervical Intraepithelial Neoplasia (CIN), and high-grade CIN. We sought to (1) quantify nuclear morphology and tissue architecture features by analyzing images of cervical biopsies; and (2) determine the accuracy of high-grade CIN detection via confocal microscopy relative to the accuracy of detection by colposcopic impression. Forty-six biopsies obtained from colposcopically normal and abnormal cervical sites were evaluated. Confocal images were acquired at different depths from the epithelial surface and histological images were analyzed using in-house software.


RESULTS
The features calculated from the confocal images compared well with those features obtained from the histological images and histopathological reviews of the specimens (obtained by a gynecologic pathologist). The correlations between two of these features (the nuclear-cytoplasmic ratio and the average of three nearest Delaunay-neighbors distance) and the grade of dysplasia were higher than that of colposcopic impression. The sensitivity of detecting high-grade dysplasia by analysing images collected at the surface of the epithelium, and at 15 and 30 μm below the epithelial surface were respectively 100, 100, and 92 %.


CONCLUSIONS
Quantitative analysis of confocal fluorescence images showed its capacity for discriminating high-grade CIN lesions vs. low-grade CIN lesions and normal tissues, at different depth of imaging. This approach could be used to help clinicians identify high-grade CIN in clinical settings.
Imaging Unit, Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, BC, V5Z 1L3, Canada. fsheikhzad@bccrc.ca.|Department of Electrical Engineering, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada. fsheikhzad@bccrc.ca.
Fahime
F
Sheikhzadeh
Department of Electrical Engineering, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada. rababw@ece.ubc.ca.
Rabab K
RK
Ward
Imaging Unit, Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, BC, V5Z 1L3, Canada. acarraro@bccrc.ca.
Anita
A
Carraro
Imaging Unit, Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, BC, V5Z 1L3, Canada. zchen@bccrc.ca.
Zhao Yang
ZY
Chen
Department of Pathology, British Columbia Cancer Agency, Vancouver, BC, V5Z 4E6, Canada. dvanniek@bccancer.bc.ca.
Dirk
D
van Niekerk
Division of Gynaecologic Oncology, Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada. Dianne.Miller@vch.ca.
Dianne
D
Miller
Division of Gynaecologic Oncology, Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada. Thomas.Ehlen@vch.ca.
Tom
T
Ehlen
Imaging Unit, Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, BC, V5Z 1L3, Canada. cmacaul@bccrc.ca.
Calum E
CE
MacAulay
Brookdale University Hospital and Medical Center, Brooklyn, NY, 11212, USA. michelefollen@hotmail.com.
Michele
M
Follen
Imaging Unit, Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, BC, V5Z 1L3, Canada. plane@bccrc.ca.|Department of Electrical Engineering, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada. plane@bccrc.ca.
Pierre M
PM
Lane
Imaging Unit, Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, BC, V5Z 1L3, Canada. mguillau@bccrc.ca.
Martial
M
Guillaud
D000328:Adult; D003127:Colposcopy; D005260:Female; D006801:Humans; D018613:Microscopy, Confocal / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D008875:Middle Aged; D060787:Neoplasm Grading; D010641:Phenotype; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000473:pathology; D055815:Young Adult; D002578:Uterine Cervical Dysplasia / Q000175:diagnosis* / Q000473:pathology