Colposcopy and additive diagnostic value of biopsies from colposcopy-negative areas to detect cervical dysplasia

Introduction: We evaluated colposcopy in the routine diagnostic workup of women with abnormal cervical cytology, as well as the diagnostic value of endocervical curettage material and biopsies taken from colposcopy-positive and colposcopy-negative quadrants of the cervix.

Material and methods: This cross-sectional study included 297 nonpregnant women with abnormal cervical cytology and no prior treatment for cervical dysplasia or cancer. All women underwent gynecological examination, colposcopy, endocervical curettage, and had cervical biopsies taken. Colposcopy was considered satisfactory if the squamocolumnar junction was fully visible, and biopsies were taken from all four quadrants of the cervix, regardless of colposcopy results.

Results: In all, 130 of the women in our study had satisfactory colposcopy results and were diagnosed with cervical intraepithelial neoplasia grade 2 or worse (CIN2+), 61% via a colposcopy-positive biopsy and 39% via a colposcopy-negative biopsy. Eighty-seven of them had positive colposcopy results, but CIN2+ was histologically verified from colposcopy-positive biopsies in 91% (n = 79) and from colposcopy-negative biopsies in 9% (n = 8). The remaining 43 women with CIN2+ had negative colposcopy findings, so their diagnosis was verified in colposcopy-negative biopsies. The sensitivity of colposcopy alone to detect CIN2+ was 61% (95% CI 52-69).

Conclusions: In the present study, colposcopy was not a stand-alone diagnostic method. Colposcopy-negative biopsies had a clear additive value, identifying a substantial proportion of women with both positive and negative colposcopy results with treatment-worthy cervical dysplasia. Endocervical curettage material had little diagnostic value in this study.