Accuracy of colposcopy-directed biopsy in detecting early cervical neoplasia

Objective:

Gold standard for diagnosing cervical intraepithelial neoplasia (CIN) is the colposcopy-directed biopsy. Reported results in the literature of the accuracy of colposcopy-directed biopsy are highly variable. This retrospective study was performed to determine the accuracy of colposcopy-directed biopsy in the Dysplasia Unit of the university hospital in Erlangen.

Material:

This retrospective analysis concludes 641 women comparing colposcopy-directed biopsy to the final histology obtained by large loop excision or hysterectomy examined between January 2014 and June 2017. Histological results were divided into normal, low grade cervical squamous intraepithelial lesions (LSIL), high grade cervical squamous intraepithelial lesions (HSIL) and carcinoma.

Results:

In total 505 of 641 women were diagnosed with HSIL in the colposcopy-directed biopsy. In 401 (79,4%) of these 505 women the diagnosis of HSIL was confirmed by the final operation. 16 (3,1%) women were underdiagnosed by final histology showing cervical cancer. 88 women (17,4%) were over diagnosed with LSIL or benign histology in the results of the operation.

Conclusion:

The technique of biopsy is easily carried out with only little distress for women. It shows satisfying results. 3,1% of all women diagnosed by HSIL were underdiagnosed and finally had an invasive cancer. Accuracy mainly depends on the experience of the examiner. Other reasons for missing the most severe spot of the lesion are the extension of the transformation zone (TZ) type 3, bleedings or small lesions.