Outcome of 295 possible HGSL pap tests according to cytological pattern, age and HPV status with review and reclassification of 87 cases

Abstract

<h3>Background</h3> Australian laboratories must show a biopsy proven high grade (HG) rate of >33% in ‘possible HGSL' (pHGSL) Paps. For coding and education our laboratory divides pHGSL into three groups: INCS1 (crowded sheets, indeterminate cell type), INCS2 (atypical squamous cells, high N:C ratio), INCS3 (at least LSIL, ?HSIL). <h3>Aims</h3> (1) To determine the HG biopsy rate in pHGSL Paps according to cytological pattern, age and HPV status. (2) To review 87 INCS1 slides. <h3>Methods</h3> All pHGSL Paps during 2008 were retrieved. The Western Australian Cervical Cytology Registry (WACCR) provided follow-up data. The highest biopsy abnormality was recorded. All INCS1 slides were reviewed. <h3>Results</h3> Of 295 women, 229 had biopsy follow-up. For INCS1 the HG rate was 29% while for INCS2 and INCS3 the HG rate was 43% each. Review of 87 INCS1 Paps resulted in fewer pHGSL reports (53, HG biopsy rate 32%). However, seven with HG biopsies were missed. In women >50 years, HG biopsy rate was 19%. The sensitivity of HPV testing in 84 women was 86% for a HG abnormality. <h3>Conclusions</h3> Crowded sheets of uncertain cell type gives the lowest HG biopsy rate but cytological review gives no better results. Human papillomavirus (HPV) testing especially in older age groups would improve accuracy.