To evaluate the test characteristics of colposcopy performed on women with positive visual inspection with acetic acid (VIA) and/or human papillomavirus (HPV) tests using histology as gold standard.
A total of 30,773 women were screened by VIA and high-risk HPV test. Hybrid Capture 2 (HC2) technique was used for HPV detection. All women positive on VIA had colposcopy immediately and the HC2 positive women were recalled later for colposcopy. Among the test negative women 8.7% had colposcopy. The International Federation of Cervical Pathology & Colposcopy (IFCPC) 2011 nomenclature was used for classification of abnormalities. All women with Grade-1 or worse lesions had biopsies. Biopsies were also obtained from HC2 positive women with normal colposcopy.
Colposcopy and satisfactory biopsy reports were available from 2466 women. Overall strength of agreement between colposcopy and histologic classification of cervical neoplasias was poor (kappa=0.17). Previous studies evaluating colposcopy in cytology-based programs also observed such poor agreement. Agreement was better when colposcopy was done in HC2-positive than in VIA-positive women. Sensitivity of colposcopy to detect high-grade squamous intraepithelial lesions (HSIL) was 84.8% after correction of verification bias, again comparable to sensitivities of colposcopy on cytology-positive women. Positive predictive value of colposcopy was significantly higher in VIA-positive than in HC2-positive women. Random punch biopsies detected 13.6% of the HSILs in absence of colposcopic abnormalities and all of them were HC2 positive.
Sensitivity of colposcopy and agreement between colposcopic and histologic diagnosis are comparable between cytology based and non-cytology based cervical cancer screening programs.