A Modified Direct-Smear Processing Technique Employing Two-Step Centrifugation/Fixation Is Useful for Detecting High-Grade Urothelial Carcinoma

Abstract

Objective: To demonstrate the usefulness of a direct-smear processing technique employing two-step centrifugation/fixation processing (TSCFP) in the cytoscreening of high-grade urothelial carcinoma (HGUC). Study Design: Using the T24 HGUC cell line, we compared the cell yield and the morphological preservation of preparations concurrently processed by direct-smear, SurePath, ThinPrep, and TSCFP techniques. A total of 287 urine cytology cases subjected to TSCFP over a period of 6 years were reviewed and reclassified according to the Paris System for Reporting Urinary Cytology (PSRUC) and correlated with histology results. Results: TSCFP of T24 cells demonstrated good cell yield with a recovery rate of about 70%. Diagnostic features of HGUC, such as a high nuclear/cytoplasmic ratio and irregular/hyperchromatic chromatin, were better discovered in TSCFP smears than in smears prepared with the other methods. Cytological evaluation of 287 voided urine specimens revealed that the rate of unsatisfactory preparations was quite low (0.30%) and the overall sensitivity, specificity, and positive and negative predictive values for urothelial carcinoma were 0.719, 0.923, 0.973, and 0.462, respectively. Conclusion: TSCFP was able to provide adequate preparations for detecting HGUC in urine cytology and could be considered as a promising processing method according to the principal purpose of PSRUC.

Quantitative cytomorphological comparison of SurePath and ThinPrep liquid‐based cytology using high‐grade urothelial carcinoma cells

“…This is probably the result of the three‐dimensional structure of cells on SurePath slides. These results were similar to previous studies comparing qualitative cytomorphology using SurePath and ThinPrep 9,11 . Toyonaga et al 11 reported that T24 cells (a cell line established from a patient with urinary bladder cancer) on ThinPrep slides exhibited cytoplasmic and nuclear flattening; meanwhile, severe cell shrinkage and hyperchromasia made nuclear details difficult to observe on SurePath slides in some cases.…”

“…These results were similar to previous studies comparing qualitative cytomorphology using SurePath and ThinPrep 9,11 . Toyonaga et al 11 reported that T24 cells (a cell line established from a patient with urinary bladder cancer) on ThinPrep slides exhibited cytoplasmic and nuclear flattening; meanwhile, severe cell shrinkage and hyperchromasia made nuclear details difficult to observe on SurePath slides in some cases. In addition, Michael et al 9 related that nuclear shrinkage often decreases the N:C ratio using the SurePath method.…”

“…In recent years, comparative studies of the ThinPrep and Cytospin methods have assessed diagnostic accuracy and quantitative cytomorphology based on TPS and reported no significant differences 4,8 . Although several studies compared the conventional method with ThinPrep or SurePath, few studies compared ThinPrep and SurePath using non‐gynaecological specimens 9‐11 . ThinPrep and SurePath are both classified as LBC methods, though they are likely to be different cytomorphologically because they have different principles.…”

Relationship between Liquid-Based Cytology Preservative Solutions and Artificial Intelligence: Liquid-Based Cytology Specimen Cell Detection Using YOLOv5 Deep Convolutional Neural Network

“…SurePath is known to produce a single-cell 3D composition with considerable nuclear shrinkage by simple sedimentation of cells on a slide surface without any applied pressure. This processing artifact can make the slide difficult to interpret because the cell shrinkage obscures the details of the nucleus [30, 31]. The nuclear darkness of the SurePath specimens was greater than that of ThinPrep [32].…”