The significance of ASC-H and LSIL dual interpretation with risk stratification: one institution experience
Abel A Gonzalez1, Akosua Ametorgoh1, Diane Hamele-Bena1
1Department of Pathology and Cell Biology, Columbia University, New York, NY.
Introduction:
The 2014 Bethesda System categorizes squamous lesions as low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL). It also includes intermediate morphologic terminology, such as atypical squamous cells of undetermined significance (ASC-US) and atypical squamous cells, cannot rule out a high grade squamous intraepithelial lesion (ASC-H). Consensus is lacking if when ASC-H is present in an unequivocal LSIL (LSIL + ASC-H) versus ASC-H alone predicts a neoplasm with a different biologic behavior and which is its association with high-risk human papillomavirus (HPV).
Materials And Methods:
We reviewed the Columbia University Medical Center Pathology department patient's database from October 2012 through December 2014 and found 2498 cytology samples of LSIL, ASC-H, HSIL, and LSIL + ASC-H with both follow-up histologic samples and HPV tests by Roche cobas. Our objective was to identify, if any, differences in biologic behavior and HPV status present in LSIL + ASC-H compared with ASC-H and other lesions.
Results:
CIN2+ was documented in tissue examination in 102 from 311 LSIL + ASC-H (32.8%), 101 from 219 ASC-H (46.1%), 252 from 326 HSIL+ (77.3%), and 150 from 1642 LSIL (9.08%). HPV distribution shows significant differences between all diagnostic categories.
Conclusions:
LSIL + ASC-H appears to have a distinctive HPV distribution pattern that clearly differs from ASC-H and LSIL and approaches HSIL; however, the predictive value for CIN2+ appears higher for ASC-H than LSIL + ASC-H. Our literature review identified conflicting findings, probably suggesting a lack of reproducibility in cytologic criteria and the need for consistent inclusion of ASC-H and LSIL when both are present.
