The use of p16/Ki-67 dual staining technology on cervical cytology of patients undergoing a LLETZ procedure

Objectives: The main objective of this prospective observational study was to investigate the diagnostic performance of the p16/Ki-67 dual stain technique (DST) for detecting CIN 2+ in a LLETZ referral setting. Test performances were compared with HR-HPV testing and Pap cytology. Methods: All patients referred for a LLETZ procedure were candidates for participation in this trial. A total of 110 patients were enrolled between October 2016 and March 2017. From each participant, a cervical cytology sample was obtained before the onset of the LLETZ procedure. On each sample, the dual stain technique (Roche CINtec PLUS (R) test), Pap cytology and an HPV DNA assay (identifying 17 different HPV types) were performed. Results: The overall disease prevalence of CIN 2+ was 56%. The mean age was 41 years, with 38% of patients being younger than 35 years. The overall sensitivity and specificity of the dual stain technique for detecting CIN 2+ was 94% (95% CI: 84.30-98.21%) and 58% (95% CI: 43.21-72.93%) respectively with a PPV of 74% (95% CI: 67.34-80.31%) and a NPV of 88% (95% CI: 72.48-94.90%). HR-HPV testing results in a similar sensitivity of 92% (95% CI: 82.17-97.33%) but considerable lower specificity of 21% (95% CI: 11.17-33.35%) compared to the dual stain technique. At an ASCUS or worse threshold, Pap cytology had the lowest sensitivity of 89% (95% CI 78.11-95.34%) compared to dual staining and HR-HPV testing. Specificity was better (48% with 95% CI of 33.29-62.81%) than that of HR-HPV testing but not as good as the DST. Conclusion: p16/Ki-67 dual staining provides high sensitivity and improved specificity compared to HR-HPV testing and Pap cytology for detecting CIN 2+, making it an interesting tool for identifying relevant disease in patients referred for a LLETZ procedure. (C) 2018 Elsevier B.V. All rights reserved.