Summary of diagnostic standards
At the colposcopy examination the following data must be recorded (100%)
- Reason for referral
- Grade of cytological abnormality
- Whether the examination was adequate - was the entire cervix seen
- The presence or absence of vaginal and/or endocervical extension
- The colposcopic features of any lesion
- The colposcopic impression
- The type of transformation zone, ie type 1,2 or 3
- The site of any colposcopically directed biopsies
An excisional form of biopsy is recommended (95%)
- When most of the ectocervix is replaced with high-grade abnormality
- When low-grade colposcopic change is associated with high-grade dyskaryosis (severe) or worse
- When a lesion extends into the canal – sufficient canal must be removed with endocervical extension of the abnormality
Reasons for not performing a biopsy must be recorded (100%).
All women must have had a histological diagnosis established before destructive therapy (100%).
Unless an excisional treatment is planned, biopsy should be carried out when cytology indicates moderate dyskaryosis or worse, and always when a recognisable atypical transformation zone is present (100%). Pregnancy is an exception.
Of all biopsies taken (directed and excisional) more than 90% should be suitable for histological interpretation.
If colposcopically directed biopsy is reported as inadequate for histological interpretation, it should be repeated if there is a residual colposcopic lesion (95%).
For those with an adequate colposcopic examination and the entire squamo-columnar junction and entire lesion visualised, the predictive value of a colposcopic diagnosis of a high- grade lesion (CIN2 or worse) should be at least 65%.