Colposcopic Impression and Histological Outcomes: Can Looks Be Deceiving?

Introduction: A colposcopic impression (CI) is formed based on the highest grade feature of any cervical lesion during a standard colposcopic assessment. Methods: A retrospective review of all cervical biopsies undertaken in 7-day period in an Irish tertiary level colposcopy department. The study received ethical approval in October 2023 by the hospital’s research advisory group (ref: 23609). Results: In total, 47 patients were recruited. The mean age of patients in this cohort was 39 years of age (range 25–64, standard deviation 11.3). Of these, 14 (29.8%) had previously attended for colposcopic assessment and been discharged. The most common referral smear was atypical squamous cells of undetermined significance ( n = 23; 49%). All patients referred with abnormal cytology were also positive for human papillomavirus. The majority of assessments and biopsies were undertaken by qualified nurse colposcopists ( n = 24; 51.1%). A total of 6 (12.8%) patients had CI of high-grade disease, with 4 (66.6%) confirmed histologically. A CI of low-grade disease was given for 35 (74.5%) patients. Of these, 25 (71.4%) had confirmed cervical intraepithelial neoplasia (CIN1) on biopsy. In 8 (22.9%) cases when low-grade disease was suspected, histology of CIN2 or higher was returned. Conclusion: The positive predictive value for suspected high-grade lesions (66.6%) within the time frame studied was lower than the target of 75%. The PPV for suspected low-grade lesions was higher (71.4%), although underestimation of grade was noted in 22.9% of cases. The implementation of a formal scoring system may help improve the sensitivity and specificity in identifying high-grade diseases in this unit.