Clinical utility of p16/Ki67 dual-stain cytology for detection of cervical intraepithelial neoplasia grade two or worse in women with a transformation zone type 3: A cross-sectional study

OBJECTIVE

To evaluate the clinical utility of p16/Ki67 dual-stain (DS) compared with cytology for detecting cervical intraepithelial lesion grade two or worse (CIN2+) in women with a transformation zone type 3 (TZ3).

DESIGN

Cross-sectional study.

SETTING

Colposcopy clinics in Central Denmark Region.

POPULATION

Women aged 45 years or older referred for colposcopy because of an abnormal screening test.

METHODS

All women had a cervical sample collected for cytology and DS testing and underwent large-loop excision of the transformation zone (LLETZ).

MAIN OUTCOME MEASURE

Sensitivity, specificity and negative (NPV) and positive (PPV) predictive values of DS for CIN2+ detection were compared to those of cytology.

RESULTS

Of 166 women eligible, 93 (56.0%) were included in the final analysis. Median age was 68 years (interquartile range [IQR] 63.4-70.5 years). Most women were postmenopausal (95.7%) and referred based on a positive human papillomavirus screening test (86.0%). Fifty-two women (55.9%) were DS-positive, 29 (55.8%) of whom had CIN2+ detected. Twenty-seven (29.0%) women had atypical squamous cells of undetermined significance or worse (ASC-US+), and CIN2+ was detected in 21 women (77.8%). DS had a higher sensitivity (96.7% versus 70.0% p = 0.021) and NPV (97.6% versus 86.4%, p = 0.018) compared with cytology for CIN2+ detection. In contrast, the specificity (63.5% versus 90.5% p < 0.001) and PPV (55.8% versus 77.8%, p = 0.001) were lower for DS compared with cytology.

CONCLUSIONS

Dual stain may be a valuable risk marker to guide clinical management of women with a TZ3. The superior NPV of DS suggests that a diagnostic excision may safely be avoided in DS-negative women.

Comparison of the Cervex-Brush alone to Cytobrush plus Cervex-Brush for detection of cervical dysplasia in women with a transformation zone type 3

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.