Borderline nuclear change, high-grade dyskaryosis not excluded: current concepts and impact on clinical practice

Borderline nuclear change, high-grade dyskaryosis not excluded (B/HG) is a subcategory of the borderline category recommended by the British Society for Clinical Cytology as warranting direct referral to colposcopy. This subcategory is equivalent to the Bethesda category of atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H). The purpose of this study was to determine the validity and accuracy of using B/HG to identify potential cervical intraepithelial neoplasia (CIN) grade 2 or worse (CIN2+).

Data were collected from the hospital pathology database for borderline, B/HG and high-grade cytology (moderate dyskaryosis and above), and their respective histological and colposcopic outcomes. SPSS was used for data analysis.

Of the 84,799 total cytology samples screened between July 2006 and December 2009, 5225 (6.1%) were reported as borderline, 309 (0.4%) as B/HG and 1222 (1.4%) as high-grade cytology. Thus, B/HG comprised 5.9% of the overall borderline category, in keeping with national guidelines (<10%). CIN2+ was confirmed in 86.6% of high-grade, 40.8% of B/HG and 3.0% of borderline cytology. Of 309 women reported with B/HG cytology, 239 had colposcopy. Colposcopic appearances showed a positive predictive value (PPV) of 71.8% for detecting CIN2+ and a negative predictive value of 60.7%.

The B/HG category was associated with a significantly higher incidence of CIN2+ compared with borderline cytology as a whole. This refining performance justifies its existence. Colposcopic appearances had a high PPV for detecting CIN2+. Therefore, colposcopy is recommended in patients with B/HG cytology and treatment should be offered if high-grade colposcopic changes are seen.