The CERvical Tissue AdjunctIve aNalysis (CERTAIN) study was one of the largest immunohistochemistry (IHC) studies to date. It analyzed the impact of adjunctive use of p16 IHC on diagnostic sensitivity and specificity for ≥CIN2 when p16 IHC was used according to the LAST recommendations.1
The study set included 1.100 cervical biopsies representative of a U.S. colposcopy referral population. H&E-stained slides and p16 IHC-stained slides were prepared from each specimen. The participants in the study included 70 board-certified, individual surgical pathologists (ISPs) and 3 expert gynecological pathologists. Expert consensus diagnoses [Central Pathology Review using H&E alone (CPRH&E) and a second CPR using H&E + p16 IHC (CPRH&E+p16)] were established by the expert gynecological pathologists.1
Published results from the CERTAIN trial2 showed that:
- Adjunctive use of p16 IHC provides more accurate and reproducible diagnostic results in the interpretation of cervical biopsies, ensuring that more patients are treated correctly without treating a larger number of patients. In LAST cases, diagnostic accuracy, diagnostic sensitivity, and diagnostic specificity were all significantly increased for ISPH&E + p16 compared to ISPH&E.
- For cases for which pathologists requested p16 IHC according to LAST criteria, ISPs demonstrated a 10,4 % improvement in diagnostic agreement driven by an 11,8 % and 9,7 % increase in sensitivity and specificity, respectively.
- In both LAST and non-LAST cases, p16 IHC did not lead to the over-diagnosis of p16 positive CIN1 as CIN2 or the under-diagnosis of p16 negative CIN2 as CIN1. When p16 IHC was performed according to LAST criteria, there were fewer ISP CIN2 diagnoses (n=2018) than when H&E was used alone (n=2524), reassuring that the use of p16 IHC does not lead to overdiagnosis of p16-positive CIN1 as CIN2. For non-LAST cases there was a comparable 11,0 % increase in sensitivity whereas specificity decreased slightly by -0,8 %.
The CERTAIN study by Wright T., et al. can be accessed from the link below:
 Stoler M.H., et al. Routine Use of Adjunctive p16 Immunohistochemistry Improves Diagnostic Agreement of Cervical Biopsy Interpretation: Results From the CERTAIN Study. Am J Surg Pathol. 2018
 Wright T.C., et al. The CERTAIN Study Results: Adjunctive p16 Immunohistochemistry Use in Cervical Biopsies According to LAST Criteria. Am J Surg Pathol 2021