INTRODUCTION: Twenty percent of colposcopic assessments are inadequate due to a type 3 transformation zone (TZ3). In the absence of colposcopic or histological assessment, subsequent management is guided by the referral screening test. In the UK, routine cervical screening is completed by a Cervex-Brush alone. This study examines the effectiveness of a Cytobrush in addition to a standard Cervex-Brush when used in TZ3 assessment.
METHODOLOGY: An 18-month diagnostic accuracy study in a single National Health Service (NHS) Trust. Women with a TZ3 booked for large loop excision of the transformation zone (LLETZ) with a referral cytology of high-risk HPV and squamous dyskaryosis were recruited. Immediately prior to LLETZ, a Cervex-Brush plus Cytobrush liquid-based cytology sample was taken. Presence of endocervical cells was compared. Predictability of high-grade cervical intra-epithelial neoplasia (CIN2+) was by blind standardised reporting of the LLETZ histology.
RESULTS: One hundred and five women were recruited from a total eligible population of 153 cases (68.8%). Endocervical cell yield was increased with the Cervex-Brush plus Cytobrush when compared to the Cervex-Brush alone (99.1% vs 79.1%, P < .001). Irrespective of cytological grade, age or parity, there was no difference in predictability of CIN2+ between sampling methods.
CONCLUSIONS: When compared to Cervex-Brush sampling alone, the addition of a Cytobrush improves endocervical sampling but does not improve cytological predictability of CIN2+ in women with a TZ3. These data suggest that women who will reliably attend for cytological follow-up can be safely referred to primary care for a Cervex-Brush alone.