BETHESDA CLASSIFICATION OF CERVICOVAGINAL SMEARS - REPRODUCIBILITY AND VIRAL CORRELATES

Fifty-five cervicovaginal smears from women with squamous intraepithel ial lesions (SILs) were independently evaluated on two separate occasi ons by four cytopathologists using a binary classification system (the Bethesda system). Smears were categorized as low-grade (LSIL) or high -grade (HSIL) using previously published criteria. All women had subse quent cervical biopsies containing human papillomavirus (HPV) DNA ampl ified with the polymerase chain reaction and typed by restriction frag ment polymorphism analysis. Three or more observers agreed on classifi cation in 49 of 55 cases (87%); unanimous diagnoses were rendered in 3 1 cases (56%). Interobserver and intraobserver reproducibility ranged from fair to near-excellent (kappa values 0.40 to 0.63; 0.63 to 0.74, respectively). HPV types included HPV 16 (27%), 18 (7%), 31 (9%), 35 ( 4%), 39 (4%), 6 (10%), 11 (2%), novel types (30%), and multiple types (4%). High-risk HPV types (16, 18, 31, 35, and 39) were significantly associated (P = .03) with consensus HSIL diagnoses (agreement of three or more observers). This was primarily because of the strong associat ion of HPV 16 with HSIL (P = .001). After excluding HPV 16, the other high-risk HPV types (18, 31, 35, and 39) were no longer significantly associated with consensus HSIL diagnoses (P > .5). Conversely, LSIL di agnoses were significantly associated with non-high-risk HPV types (al l HPV types except 16, 18, 31, 35, and 39; P = .006). Binary cytologic al classification of cervicovaginal SILs is reproducible among cytopat hologists. Such classification correlates well with most low-risk HPV types and with the prototypic high-risk HPV 16 but not with other high -risk HPV types. Copyright (C) 1996 by W.B. Saunders Company