Reprocessing unsatisfactory ThinPrep papanicolaou tests using a modified SurePath preparation technique
Background:
The frequency of unsatisfactory gynecologic specimens has increased in the study laboratory over the last few years due to the advent of personal lubricants. Similarly, lysed blood, protein, and necrotic debris present a challenge in terms of negative cell transference caused by a clogged filter. In the current study, the authors evaluated the potential use of a modified SurePath reprocessing technique to decrease the frequency of unsatisfactory specimens.
Methods:
An aliquot for human papillomavirus testing was set aside and the remaining specimen in the ThinPrep vial was submitted for sedimentation. A methanol wash was performed using preservative that was added to the remaining sediment. The specimen was vortexed and a protein wash of Tris-buffered deionized water was added before processing. The specimens were stained using the ThinPrep staining protocol. Both the original specimen and the reprocessed specimens were manually reviewed by 1 cytotechnologist and 2 pathologists to determine specimen adequacy.
Results:
A total of 1937 ThinPrep Papanicolaou tests were reprocessed and examined. Of these, 1093 (56%) specimens were satisfactory, 624 of which (57%) demonstrated evidence of a transformation zone component. Epithelial cell abnormalities were identified in 116 specimens (10.6%), including 11 high-grade squamous intraepithelial lesion specimens (1.0%); 5 specimens with a classification of atypical squamous cells, cannot rule out a high-grade lesion (0.5%); 21 low-grade squamous intraepithelial lesion specimens (1.9%); and 79 specimens classified as atypical squamous cells of undetermined significance (7.2%).
Conclusions:
The modified SurePath processing technique was adept at handling nearly all of the challenges that biological and environmental conditions (blood, protein, lubricant, etc) present in liquid-based filter preparations. A total of 1093 (56%) of 1937 unsatisfactory ThinPrep Papanicolaou tests were converted to a satisfactory state, resulting in 116 abnormalities (10.6%) being diagnosed that otherwise would have gone undetected
