[409] Atypical Squamous Cells of Undetermined Significance (ASC-US) Associated with Atypical Repair in Liquid-Based (Surepath) Pap Tests: Prevalence of Human Papillomavirus Infections and Follow-Up Biopsy Diagnoses
Andrew C Nelson, Arbaz Samad, Samy A Amirouche, Jana L Holler, Stefan E Pambuccian. University of Minnesota Medical Center, Fairview, Minneapolis, MN
Background: Despite its use for more than two decades and the clearly formulated Bethesda system diagnostic criteria, the diagnosis of atypical squamous cells of undetermined significance (ASC-US) is still the most challenging and least reproducible diagnosis made on Pap tests. ASC-US associated with atypical reparative changes (ASC-US+ATYREP) is one of the subtypes of ASC-US recognized by the Bethesda System. Studies that have addressed the question of the significance of ASC-US+ATYREP have arrived to conflicting results, some authors even arguing against retaining this diagnostic category under ASC-US. The aim of this study was to determine the human papillomavirus (HPV) and follow-up biopsy correlates on ASC-US+ATR in an attempt to shed further light on this issue.
Design: We identified all cases diagnosed from 1/1/2003 to 12/31/2010 as ASC-US with atypical repair (ASC-US+ATYREP) that had reflex HPV testing performed by a PCR-based method using MY09/11 consensus primers and typing by RFLP. All cases were diagnosed by 2001 Bethesda System criteria on Surepath Pap tests. The prevalence of any HPV type, high-risk HPV types (HR-HPV) and HPV16/18 and the frequency of abnormal follow-up biopsies diagnosed as CIN1 and above (CIN1+) and CIN2 and above (CIN2+) in women with ASC-ATYREP was compared statistically to those of all other cases of ASC-US diagnosed within the same time interval.
Results: Of the 23077 cases diagnosed as ASC-US during the study interval, 188 (0.81%) were associated with ATYREP.
| AGE (MEAN±SD) | ALL HPV TYPES | HR-HPV TYPES | HPV TYPES 16/18 | BIOPSY RATE | CIN1+ | CIN2+ | |
| ALL ASC-US (N=23077) | 36.3±13.2 | 8937 (38.7%) | 4277 (18.5%) | 1993 (8.6%) | 4241 (18.4%) | 1845 (8%) | 581 (2.52%) |
| ASC-US+ATYREP (N=188) | 38.9±13.6 | 46 (24.5%) | 23 (12.2%) | 19 (10.1%) | 29 (15.4%) | 10 (5.3%) | 3 (1.6%) |
| ASC-US+ATYREP VS. ALL ASC-US %CHANGE | -36.8% | -34% | |||||
| ASC-US+ATYREP VS. ALL ASC-US p VALUE | 0.007 | <0.0001 | 0.029 | NS | NS | NS | NS |