Colposcopic management of high-grade referral smears: a retrospective audit supporting 'see and treat'?

The National Health Service Cervical Screening Programme monitors the quality of colposcopy services through the annual KC65 returns. The 2002 returns demonstrated that Standard 7c, which specifies a biopsy rate > or = 90% at first colposcopy visit for high-grade referrals, was not met in the assessed 3-month period. This was investigated along with the other standards.

Retrospective colposcopy records were accessed for the 597 new referrals, excluding 10 pregnant patients, seen at the colposcopy clinic at the Royal Victoria Infirmary between 1 July 2001 and 31 December 2002, following an abnormal high-grade smear. Cytology and histopathology computer records were checked for confirmation. The results were assessed against the colposcopy standards applicable at that time and the revised standards (2004).

Biopsies were taken from 94.47% (Standard > or = 90%) of women at index colposcopy visit including wire loop excision biopsies from 66.16% (87.97% of high-grade colposcopic appearances). Cervical intraepithelial neoplasia (CIN) on histology was found in 91.79% in the study group (Standard > or = 85%) and in 96.71% of index visit biopsies (Standard > or = 90%), meeting the applicable colposcopy standards. The revised 2004 standards specify a biopsy in > or = 95% of high-grade referrals and excision biopsies in 95% if colposcopic appearances are also high-grade, if colposcopy is low grade but the smear is severely dyskaryotic, or when the lesion extends into the canal. The positive predictive value of high-grade cytology for this entire group was 75.54% with CIN present in 90.95%.

From this study it appears that high-grade cytology in this centre reliably indicates high-grade CIN. Therefore, in women referred for colposcopy following a high-grade smear, excision biopsies should be performed in a higher proportion at the first visit to comply with the revised standards.