Cervical cytologic abnormalities and negative colposcopy: histologic assessment

Colposcopic assessment may be normal in the presence of severe or persistent minor cytologic abnormality. To assess the significance of negative satisfactory colposcopy in patients with abnormal cervical smears, a retrospective review was carried out on 1170 patients who had undergone out-patient loop diathermy excision for abnormal cervical cytology. Of these, 69 patients were treated for abnormal cervical cytology, despite normal colposcopic findings. Cytologic abnormalities ranged from persistent borderline changes to severe dyskariosis. Histologic assessment of the excision specimens revealed cervical intraepithalial neoplasia (CIN) in 43 (62.3%) cases, of which high-grade CIN accounted for 24 (34.8%) cases. There was good correlation between cytologic and histologic diagnosis. Simple regression analysis showed r = 0.46, P < 0.0001. The cytologic abnormality was highly predictive of the corresponding histologic diagnosis. This analysis has shown that significant intraepithelial lesions may exist despite negative colposcopic examination and highlights the need for histologic evaluation in such cases. In these circumstances, loop cone biopsy permits accurate definition of lesion severity, avoids potential undertreatment of significant lesions and causes less morbidity than conventional cone biopsy.