Nodal Burden Drives ctHPVDNA in HPV-Positive Oropharynx Cancer

In an interview with Targeted Oncology, Catherine T. Haring, MD, assistant professor in the Department of Otolaryngology at The Ohio State University - The James, discusses findings from a study examining clinicopathologic variables associated with circulating tumor HPV DNA (ctHPVDNA) in patients with HPV-positive oropharynx cancer.

The study enrolled 104 patients who underwent upfront surgery followed by adjuvant treatment guided by their final pathology report. Circulating tumor DNA (ctDNA) was measured in all 104 patients prior to surgery and in the majority of patients following surgery, allowing for analysis of both preoperative and postoperative values.

Dr Haring explains that the study evaluated a range of patient characteristics and pathologic features to identify predictors of ctHPVDNA values at both timepoints. Among the preoperative findings, nodal tumor burden emerged as the strongest predictor, with patients carrying greater volumes of nodal disease demonstrating correspondingly higher preoperative ctHPVDNA values. However, the study also uncovered findings that Dr Haring describes as somewhat counterintuitive: patients whose tumors displayed more aggressive pathologic features, specifically extranodal extension or perineural invasion, actually tended to have lower preoperative ctHPVDNA values.

Rather than contradicting existing science, Dr Haring notes that this finding is consistent with current data and is likely explained by the relationship between ctHPVDNA levels and HPV tumor integration status. When the HPV virus becomes more highly integrated into a patient's genomic DNA, lower ctHPVDNA values are observed. As a result, ctHPVDNA may serve as an indirect measure of tumor biology, reflecting the degree of viral integration rather than simply the overall aggressiveness of the disease. These findings have potential implications for how clinicians interpret ctHPVDNA values in the preoperative setting and underscore the biological complexity underlying this biomarker.