The Value of Levels and p16 Immunostains in the Follow-Up of HPV Positive-Biopsy Negative Cervical Lesions
Amberly Nunez, Janie Roberson, Allison Wrenn III, Isam Eltoum. University of Alabama at Birmingham, Birmingham, AL
Background: Current recommendations for ASC-HPV + findings with a (-) biopsy are to repeat cytology at 6 and 12 mos or repeat HPV testing at 12 mos. There are no current recommendations for the immediate assessment of ASC-HPV + and biopsy (-) specimens. We believe sampling and interpretation errors accounts for a significant number of these discrepancies and that re-review of the biopsy may reveal dysplasia, obviating the need for subsequent screening follow-up. The objective of this study is to assess if re-review of (-) biopsies and/or levels or p16 would detect undiagnosed lesions.
Design: We reviewed all ASC pap tests from 10/05-07/11 in which HPV+ patients had (-) follow-up biopsies. These biopsies were blindly reviewed by two pathologists and classified as positive, atypical and negative. Three deeper levels were performed on all (-) and atypical cases and were classified as positive, atypical or negative. p16 immunostains were ordered on atypical and equivocal cases and interpreted according to the CAP/ASCCP Lower Anogenital Squamous guidelines. The follow-up biopsies were handled in a similar manner. The number of cases detected by re-review, levels and/or p16 were calculated in comparison to follow-up biopsies as well as percentage of cases missed due to sampling and interpretation error.
Results: During the study period 2400 of 4199 ASC pap tests were (+). 853 had available biopsies; of these 240 biopsies were (-). On subsequent follow-up, 65 (27%) had a second biopsy and are the focus of this study. Upon review, 10 cases were classified as (+) (8 CIN1, 2 CIN2+). 55 cases were (-) and on deeper levels, 6 were (+) (4 CIN1, 2 CIN2+) and 2 were atypical. p16 immunostains were done in 15 cases. Of these, 5 were (+) and 10 were (-) or showed non-specific staining. In 2 cases p16 changed the diagnosis and in 3 cases it clarified the level of dysplasia. With reclassification after review, levels and p16, 17 cases were (+) (11 CIN1, 6 CIN2+) and 48 (-). Of the 48 (-) cases, squamous epithelium/transitional zone was not present in 41. Including cases that required levels for a CIN1+ diagnosis, the total number missed due to sampling was 46 of 65 (71%). On a similar review for the follow-up biopsies, 43 were reclassified as (+) and 22 as (-). Of these 43, 17 (39%), including 6/22 (27%) CIN2+, would have been detected by re-review, levels and/or p16.
Conclusions: Sampling and interpretation errors account for a significant percentage of ASC-HPV +, biopsy negative cases. We recommend re-review, deeper levels and/or p16 to identify the source of this discrepancy.
Monday, March 4, 2013 1:00 PM
Poster Session II # 87, Monday Afternoon