ASC/SIL Ratio for Cytotechnologists: A Survey of its Utility in Clinical Practice

The atypical squamous Cell to squamous intraepithelial lesion (ASC/SIL) ratio for cytotechnologists (CTs) may, correlate with screening sensitivity in some labotatory settings Whether this ratio can be applied to other laboratory settings is not known We conducted a survey of nine cytology laboratories and correlated the ASC/SIL ratio of individual CTs with other laboratory characteristics The ASC/SIL ratio for individual CTs varied from 0.6 to 4.5 (mean 19, median 15) The ASC/SIL ratio within individual laboratories varied up to 567%, 25/78 932%) CTs had an ASC/SIL ratio of less than 15, though only three of nine laboratories had more than one CT with a ratio this low Laboratories that used 100% location guided screening (ThinPrep Imaging System) were much less likely to have a CT with a ratio <15 (1/20, 5%) than laboratories that never used location guided screening (14/34, 42%, P = 0.004). In addition, the normalized variance of these same laboratories that used location guided screening was significantly lower than those that did not (normalized standard deviation 0.32 vs 0.55, P = 0.004) The ASC/SIL ratios did not correlate with laboratory volume, individual workload, or type of specimen preparation (conventional vs liquid based) The ASC/SIL ratio for CTs varies widely between and within laboratories, and may correlate with the use of location guided screening. Very low ASC/SIL ratios are unusual, and CTs with low ratios may warrant further evaluation Diagn. Cytopathol 2010:38:180-183 (C) 2009 Wiley-Liss, Inc