Lubricant-Related High Unsatisfactory Rate with ThinPrep – Can the Cellularity Be Improved?
Tatyana Kalinicheva, Sreeharsha Masineni, Muhammad Zulfiqar, Hui Guan, Sudeshna Bandyopadhyay, Paul Tranchida, Dongping Shi, Shashi Madan, Tamar Giorgadze, Inderpreet Dhillon, Maria Luehmann, Joseph Thompson, Oudai Hassan, Vinod Shidham. Wayne State University School of Medicine and Detroit Medical Center, Detroit, MI
Background: As compared to other cervical cytology specimens, ThinPrep® (TP) has relatively higher unsatisfactory rate (3.5%). Interference due to lubricant-like debris (LUBE) is one of the most common causes for unsatisfactory rate for TP. A prospective study was performed after IRB approval to address this limitation.
Design: 1000 cases of unsatisfactory TP (over 5½ months) were analyzed for different causes. A standardized protocol based on the principle of washing with PreservCyt® was applied to prepare repeat TP if the residual specimen was available. All repeat TP were evaluated by 2 cytotechnologists followed by 6 cytopathologists.
Results: Out of 1000 specimens, 677 were unsatisfactory due to scant cellularity with LUBE interference. Other causes such as scant cellularity, blood, atrophic cellular changes, inflammation, atrophic vaginitis etc. were observed in remaining cases. 33/1000 (3%) specimens were virtually acellular. Out of 530 available residual specimens, 377 (71%) with LUBE were analyzed after repeat TP. Improved cellularity was noted in 177 (47%) specimens, but only 73 (42%) were satisfactory. 56 (32%) cases were cellular and 17 (10%) cases showed borderline cellularity (just over 5,000 cells per TP) (Figure 1).
Satisfactory repeat TP showed 89% NILM, 8% ASCUS, 1% LSIL, 1% ASC-H, 1% AGUS. These numbers were compared with the routine results on satisfactory TP in same population during similar period, studied as six different slots of sample sizes comparable to the current numbers over one year period which overlapped with this study. Statistical analysis with Chi-square test showed statistically insignificant p value more than 0.05 confirming that the results related to detection of abnormal cells in repeat TP were comparable to the general trend.
Conclusions: 1. A repeat TP with a simple wash protocol is recommended to improve unsatisfactory rate of TP cervical cytology without affecting the final interpretation.
2. Although the cellularity improved in 47% of specimens, only 19% (73 out of 377) showed adequately diagnostic cellularity. This emphasizes the significance of avoiding lubricant contamination as the preferred recommendation.
Monday, March 4, 2013 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 53, Monday Morning