Abstract 3680: Comparison of risk of advanced cervical lesions among women with first detection of atypical squamous cells, atypical glandular cells, and low-grade squamous intraepithelial lesions by Pap smear

Abstract

Abstract The study aimed to examine the incidence of invasive cervical cancer (ICC), cervical carcinoma in situ (CIS), and cytologic high-grade squamous intraepithelial lesions (HSIL) or more severe cytologic lesions among women detected their first atypical squamous cell undetermined of significance (ASC), atypical glandular cells (AGC), and low-grade squamous epithelial lesions (LSIL), and to estimate the associations between the subsequent follow-up attending and risks of developing cervical cancer. National cervical cancer screening program in Taiwan has been implemented since 1995, all screening records are mandatory to report, and a centralized screening database has been established as well. The first cytologic abnormalities, included 110,561 ASC cases, 8,339 AGC cases, and 45,671 LSIL cases, and cytologic HSIL or above lesions were identified from Taiwan cervical cancer screening registry. Women received Pap smear or biopsy in one year after their first cytologic abnormalities were considered have attended subsequent follow-up. Cervical cancers were ascertained from national cancer registry in Taiwan until Dec, 31st, 2007. Hazard ratios were estimated by Cox's proportional hazards model, and cumulative incidences were estimated by Nelson-Aalen method. There was at least 14% reduction of CIS and 23% reduction of ICC if women attended screening two years before their first abnormalities, and at least 32% reduction of CIS and 58% reduction of ICC if they attended screening within two years. Follow-up attending for the first abnormality significantly reduced 13% to 53% of cytologic HSIL occurrence, 40% to 49% of CIS occurrence, and 52% to 71% of ICC occurrence. AGC is the most clinical significant lesion compared with ASC and LSIL, and is suggestive to include in the positivity follow-up system. Compared to LSIL, ASC is less risky to develop cytologic HSIL, similar risk to develop CIS, and possesses more risk to develop ICC. Subsequent follow-up attendance for their first abnormality and previous negative smear detection were inversely associated with cervical cancer occurrence. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3680. doi:10.1158/1538-7445.AM2011-3680