RESUMO
BACKGROUND: Human papillomavirus (HPV) is causally linked to oropharyngeal squamous cell carcinoma (OPSCC). Testing for plasma tumor tissue modified viral (TTMV)-HPV DNA has emerged as a biomarker strategy for post-treatment surveillance to identify recurrent disease. We aimed to understand the prognostic and predictive potential of TTMV-HPV DNA when monitoring patients who had developed recurrent or metastatic (R/M) HPV+OPSCC. METHODS: This retrospective observational cohort study included 80 patients from 4 academic centers with R/M HPV+OPSCC if they had ≥ 1 plasma TTMV-HPV DNA test obtained at any point during their R/M disease course. Physician-reported clinical data and treatment history were captured in a centralized database, along with investigator-assessed response to therapy and survival. Descriptive statistics and non-parametric tests of association were employed along with survival analyses (Kaplan-Meier method). RESULTS: Sixteen (20 %) patients had ≥ 5 test results over time. Consecutive TTMV-HPV DNA tests were performed a median of 73 days apart. Median TTMV-HPV DNA scores were higher with an increasing per-patient number of metastatic sites (<2 vs. 2+; p < 0.01). Score changes over time were influenced by R/M treatment modality and became undetectable in 67 % (12/18) of patients who achieved a complete response to R/M therapy. Patients with detectable scores at last follow-up had significantly worse survival compared with those who were undetectable (log-rank test, p < 0.01). CONCLUSIONS: TTMV-HPV DNA appears useful as a prognostic tool for monitoring response to therapy in the R/M setting. In the future, TTMV-HPV DNA could be explored as an exploratory clinical trial endpoint in the metastatic setting.
RESUMO
PURPOSE: Human papillomavirus (HPV) is causally linked to oropharyngeal squamous cell carcinoma (OPSCC). Consensus guidelines recommend clinical exams and imaging in decreasing frequency as part of posttreatment surveillance for recurrence. Plasma tumor tissue modified viral (TTMV)-HPV DNA testing has emerged as a biomarker which can inform disease status during surveillance. EXPERIMENTAL DESIGN: This retrospective observational cohort study involved 543 patients who completed curative-intent therapy for HPV-associated OPSCC between February 2020 and January 2022 at eight U.S. cancer care institutions. We determined the negative predictive value (NPV) of TTMV-HPV DNA for recurrence when matched to physician-reported clinical outcome data (median follow-up time: 27.9 months; range: 4.5-154). RESULTS: The cohort included mostly men with a median age of 61 who had locoregionally advanced disease. HPV status was determined by p16 positivity in 87% of patients, with a positive HPV PCR/ISH among 55%; while pretreatment TTMV-HPV DNA status was unknown for most (79%) patients. Patients had a mean of 2.6 tests and almost half had three or more TTMV-HPV DNA results during surveillance. The per-test and per-patient sensitivity of the assay was 92.5% [95% confidence interval (CI): 87.5-97.5] and 87.3% (95% CI: 79.1-95.5), respectively. The NPV for the assay was 99.4% (95% CI: 98.9-99.8) and 98.4% (95% CI: 97.3-99.5), respectively. CONCLUSIONS: TTMV-HPV DNA surveillance testing yields few false negative results and few missed recurrences. These data could inform decisions on when to pursue reimaging following first disease restaging and could inform future surveillance practice. Additional study of how pretreatment TTMV-HPV DNA status impacts sensitivity for recurrence is needed.