%0 Journal Article
%T P16 and Ki67 Immunostains Decrease Intra- and Interobserver Variability in the Diagnosis and Grading of Anal Intraepithelial Neoplasia (AIN)
%A Ann E. Walts
%A Juan Lechago
%A Bing Hu
%A MaryBeth Shwayder
%A Lynn Sandweiss and Shikha Bose
%J Clinical Medicine Insights: Pathology
%D 2012
%I 
%X Background: Significant variation is reported in the diagnosis of HPV-associated AIN. We previously observed that bandlike positivity for p16 in >90% of contiguous cells coupled with Ki67 positivity in >50% of lesional cells is strongly associated with high grade AIN. This study was undertaken to determine if addition of p16 and Ki67 immunostaining would reduce inter- and intraobserver variability in diagnosis and grading of AIN. Design: H&E stained slides of 60 anal biopsies were reviewed by three pathologists and consensus diagnoses were achieved: 25 negative, 12 low (condyloma and/or AIN I) and 23 high (9 AIN II and 14 AIN III) grade lesions. The H&E stained slides were diagnosed independently by three additional (ˇ°participantˇ±) pathologists. Several weeks later they re-examined these slides in conjunction with corresponding p16 and Ki67 immunostains. Results: Addition of p16 and Ki67 immunostains reduced intra- and interobserver variability, improved concurrence with consensus diagnoses and reduced two-step differences in diagnosis. Negative and high grade AIN diagnoses showed the most improvement in concurrence levels. Conclusion: Addition of p16 and Ki67 immunostains is helpful in the diagnosis and grading of AIN.
%U http://www.la-press.com/p16-and-ki67-immunostains-decrease-intra--and-interobserver-variabilit-article-a545