2018 ASCO Annual Meeting!
Session: Head and Neck Cancer
Type: Poster Session
Time: Saturday June 2, 1:15 PM to 4:45 PM
Location: Hall A
Session: Head and Neck Cancer
Type: Poster Discussion Session
Time: Saturday June 2, 4:45 PM to 6:00 PM
High-accuracy HPV testing versus p16 IHC using multiple clinically relevant outcomes: The University of Chicago Experience.
Head and Neck Cancer
2018 ASCO Annual Meeting
Poster Board Number:
Poster Discussion Session (Board #8)
J Clin Oncol 36, 2018 (suppl; abstr 6020)
Author(s): Sara Kochanny, Corey Christian Foster, Arun Khattri, Ryan J. Brisson, Allison Dekker, Elaine Klema, Rajesh Acharya, Jeremy Segal, Mark W. Lingen, Nicole Cipriani, Alexander T. Pearson, Vassiliki Saloura, Everett E. Vokes, Tanguy Y. Seiwert; Section of Hematology/Oncology, Department of Medicine, The University of Chicago Medicine, Chicago, IL; Department of Radiation & Cellular Oncology, The University of Chicago Medicine, Chicago, IL; Oakland University William Beaumont School of Medicine, Rochester, MI; University of Chicago, Chicago, IL; The University of Chicago Medicine and Biological Sciences, Chicago, IL; University of Michigan, Ann Arbor, MI
Background: The current most widely used standard for HPV status testing in head & neck cancer is p16 IHC. However, p16 IHC is a surrogate method which does not test directly for HPV genetic material and p16 expression is known to occur in HPV- tumors also. Furthermore, HPV strain identification can influence prognosis necessitating HPV typing. We have developed a dual testing method using both p16 IHC in combination with multiplex HPV PCR to accomplish the high sensitivity HPV testing with overall high specificity, sensitivity, and overall accuracy. Methods: As part of our clinical experience, we evaluated the HPV status of 317 patients with head & neck cancer suspicious for HPV involvement using a dual testing method with both p16 IHC and multiplex PCR. For discrepant cases where p16 and PCR do not agree, we confirmed status by performing genetic profiling (OncoPlus). The sensitivity and specificity of the method was tested with a combined validation cohort of 87 HPV negative (n = 48) and HPV positive (n = 39) tumor samples. Results: In our clinical experience with oropharyngeal HPV testing, including as part of de-escalation trials, we identified that 5% of oropharynx cases have false positive p16, where the PCR does not support HPV. 8% of PCR confirmed HPV positive cases were non-HPV16, which were associated with poorer prognosis. In the combined HPV- and HPV+ validation cohort, sensitivity was 97.4%, specificity 93.75%, PPV was 95%, NPV = 97.8%, with an overall accuracy of 95.4%. Conclusions: Dual testing by p16 and PCR is feasible, and increases accuracy. Using p16 alone results in a 5% false positive and 8% misclassification rate for HPV(-) and non-HPV16 cancers, respectively. In the era of de-escalation where treatment decisions are based on HPV status, it is critical to identify patients who are actually HPV(-) or non-HPV16. Such patients likely should not be treated on de-escalation trials unless appropriate safeguards are in place.
2. Discovery of a reliable and robust methylome classifier of HPV driven head and neck cancer with favorable response to chemoradiation: A multicenter study of the German Cancer Consortium Radiation Oncology Group (DKTK-ROG).