p16INK4A and Ki-67 immunostaining on cell blocks from residual ThinPrep material is helpful in identifying significant preneoplastic cervical lesions.

Cell blocks can be prepared from residual ThinPrep material, and immunohistochemical staining can be used. The objectives of the current study were (1) to investigate the role of cell block preparation in identifying significant preneoplastic cervical lesions; and (2) to assess the diagnostic value of p16(INK4A) and Ki-67 immunostaining on cell blocks to identify significant preneoplastic cervical lesions. Samples from residual substances of ThinPrep from 79 patients were collected for cell block preparations. Cell block sections and histological sections of the same patients were stained with hematoxylin and eosin, and were immunostained with antibodies against p16(INK4A) and Ki-67 antigen. The sensitivity and specificity for p16(INK4A) and Ki-67 immunostaining to detect high-grade squamous intraepithelial neoplasia were 95.12% and 73.68%, respectively. The positive predictive value and negative predictive value were 79.59% and 93.33%, respectively. Immunostaining of cell blocks for p16(INK4A) and Ki-67 exhibited a statistically significant association with the presence of significant lesions on cell blocks (P < 0.05). p16(INK4A) and Ki-67 immunostaining on cell blocks from residual ThinPrep material is helpful in identifying significant preneoplastic cervical lesions.