Evidence for increasing usage of low‐grade squamous intraepithelial lesion, cannot exclude high‐grade squamous intraepithelial lesion (LSIL‐H) Pap test interpretations

Abstract

BACKGROUND: Pap test (PT) interpretations of low-grade squamous intraepithelial lesion (LSIL), cannot exclude high-grade squamous intraepithelial lesion (HSIL), or LSIL-H, are used in many laboratories; however monitoring its usage for quality assurance purposes is understudied. METHODS: PTs from 2005 to 2010 were collected, and yearly frequencies of LSIL, HSIL, LSIL-H, and atypical squamous cells, cannot exclude HSIL (ASC-H) as a function of total PTs and total squamous intraepithelial lesions (SILs) were calculated. Two-year risk of cervical intraepithelial neoplasia 2 (CIN2) or worse (CIN2+) and CIN 3 or worse (CIN3+) was calculated. RESULTS: A total of 352,220 PTs were identified including 17,301 abnormal PTs. LSIL-H usage increased from 2005 to 2010 (from 0.28% of total PTs in 2005 to 0.61% in 2010, P \u3c .01; from 5.8% of total SILs in 2005 to 12% in 2010, P \u3c .001). HSIL usage decreased significantly from 2005 to 2010 (from 0.7% of total PTs in 2005 to 0.48% in 2010, P = .048; from 14.5% of total SILs in 2005 to 9.5% in 2010, P \u3c .01). Usage of LSIL and ASC-H did not change. Two-year risk of CIN2+ and CIN3+ for HSIL increased significantly from 2005 to 2010 (P \u3c .01). Two-year risk of CIN2+ and CIN3+ for LSIL-H did not change significantly from 2005 to 2010. CONCLUSIONS: The frequency of LSIL-H interpretations is significantly increasing at our institution, with a significant decrease in HSIL interpretations over the same period. Two-year risk of CIN2+ and CIN3+ for HSIL increased significantly as usage of LSIL-H increased and that of HSIL decreased. Laboratories using LSIL-H may benefit from monitoring its frequency to ensure its appropriate use. Cancer (Cancer Cytopathol) 2014;122:123-7. (c) 2013 American Cancer Society

Bethesda 2014 Implementation and Human Papillomavirus Primary Screening: Practices of Laboratories Participating in the College of American Pathologists PAP Education Program

“…A publication based on a 2011 CAP survey showed that 80.9% of laboratories were using LSIL-H to report such specimens. 1 Although many papers in the literature have reported use of the LSIL-H category, [15][16][17][18][19] for TBS 2014, this term was considered but not endorsed. Instead, TBS 2014 recommends that such cases be interpreted as ASC-H with a comment that LSIL is also present.…”

Low‐grade squamous intraepithelial lesion, cannot rule out high‐grade lesion: Diagnosis, histological outcomes and human papillomavirus results

“…In our cohort, LROH comprised only 0.30% of all Pap tests evaluated during the study interval which are comparable with previously reported rates. For example, Alsharif et al reported the rate as 0.35%, Walavalkar et al reported 0.41%, Shidham et al reported a 0.19% rate, Elsheikh et al reported 0.15%, Barron et al reported a 0.18% rate and Owens et al reported 0.50%.…”

“…Briefly, LROH diagnosis is used in our practice in cases with unequivocal LSIL showing cells suggesting HSIL, which are insufficient, either qualitatively or quantitative for a definitive HSIL diagnosis, as well as other features described in literature . A common scenario includes the presence of few hyperchromatic crowded groups, atypical keratinised cells or scattered small squamous cells with increased nuclear to cytoplasmic ratio, variable nuclear hyperchromasia and nuclear membranes irregularities in a background of LSIL (Figure ).…”

“…Several reported studies have indicated that patients with LROH/LSIL‐H appeared to have an intermediate risk of harbouring or developing high‐grade squamous lesions on biopsy and a different HPV prevalence compared with LSIL and ASC‐H, ranging from 22.8% to 59% of cases . Because of the increased incidence of high‐grade lesions found on histology, comparable to patients with HSIL, it has been proposed that these patients may require a clinical management similar to HSIL diagnosis …”