Atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion: diagnostic features in surepath™ cervical samples.

This study was undertaken to identify the situations in which a diagnosis of "Atypical squamous cells, cannot exclude a high-grade squamous intraepithelial lesion (ASC-H)" is offered in SurePath™ cervical samples and to identify cytological criteria helpful in predicting high-grade disease. 2,335 (3.4%) SurePath samples reported as atypical squamous cells (ASC) over a period of 2 years, including 1,112 cases with known hrHPV status were retrieved. 105/1,112 cases were categorized into ASC-H, and slides were available for review in 88/105 cases. These 88 samples were divided into two categories based on follow-up histological outcome and hrHPV status-category A: cases with CIN2+ lesions on follow-up (n = 48) and category B: cases with ≤CIN1 lesions or hrHPV negative status (n = 40). 78% (82/105) cases of ASC-H tested positive for hrHPV. Overall CIN2+ lesions were found in 50.3% (53/105) cases. Of 88 cases reviewed, HCGs were noted in 56.3% (27/48) cases in category A and 75% (30/40) cases in category B. Dispersed metaplastic cells and scattered small atypical cells were seen in 37.5% (18/48) cases in category A and 12.5%(5/40) in category B. The majority of cases with dispersed atypical cells had <20 cells/sample and cases with HCGs had <10 HCGs per sample. The majority of the cases reported as ASC-H contained HCGs. Of these groups with nuclear crowding, disorganization and those with steep edges ("blocks") are likely to predict high-grade disease. The samples with only dispersed atypical cells had <20 cells/sample in majority of cases. In these, a disproportionate and especially high nuclear: cytoplasmic ratio and irregular chromatin were the most useful features in predicting high-grade disease.