Detectable Post-operative Circulating Tumor Human Papillomavirus (HPV) DNA And Association with Recurrence in Patients with HPV-Associated Oropharyngeal Squamous Cell Carcinoma

Human Papillomavirus Testing in Head and Neck Carcinomas: Guideline Update

CONTEXT.—

In 2018, an evidence-based guideline was published by the College of American Pathologists to develop recommendations for the testing, application, interpretation, and reporting of high-risk human papillomavirus and surrogate marker tests in head and neck carcinomas. Substantial new evidence has prompted a review, including data on human papillomavirus (HPV) in nonoropharyngeal anatomic sites, HPV global rates, p16 immunohistochemistry, and HPV testing performance in cytology specimens, and performance of p16 immunohistochemistry as a surrogate marker.

OBJECTIVE.—

To assess research published since the release of the original 2018 guideline and to update evidence-based recommendations for HPV testing in head and neck carcinomas.

DESIGN.—

The College of American Pathologists convened a panel of experts to update the guideline following the standards established by the National Academy of Medicine for developing trustworthy clinical practice guidelines. The expert panel defined the key questions and performed a systematic review of the literature. Using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, recommendations were updated on the basis of available evidence, certainty of that evidence, and key judgments.

RESULTS.—

Seven strong recommendations, 4 conditional recommendations, and 5 good practice statements are offered in the guideline update.

CONCLUSIONS.—

The updated guideline statements provide direction on the nature of HPV testing in various head and neck specimens (including key updates based on new research on sinonasal squamous cell carcinoma) and expanded guidance on specific scenarios and practice settings. The goal is to improve and standardize, where possible, HPV testing across diverse pathology practice settings and different countries.

Emerging Proximal Liquid Biopsy Approaches for Detecting Residual Disease and Predicting Recurrence in Head and Neck Cancer: A Review and Proposal of Novel Liquid Staging

BACKGROUND

Head and neck squamous cell carcinoma remains challenging due to high recurrence rates and poor survival outcomes. Developing precise technologies for disease burden assessment, treatment response, and minimal residual disease (MRD) surveillance is crucial for improving prognosis.

METHODS

This review explores the potential of liquid biopsy for MRD and recurrence detection. A novel liquid TNM (LiTNM) staging system is introduced, integrating biomarkers from saliva, surgical drain lymphatic fluid (SLF), and peripheral blood.

RESULTS

Proximal liquid biopsies, particularly saliva and SLF, offer advantages due to their proximity to the tumor microenvironment. Saliva demonstrates high sensitivity in HPV-associated oropharyngeal cancers, while SLF holds potential in identifying early postoperative recurrence. Despite these advancements, standardization and validation remain challenges.

CONCLUSIONS

Liquid biopsy approaches show promise for postoperative disease monitoring, yet their clinical implementation remains in the early stages. The proposed LiTNM staging system could complement TNM staging by providing a molecular framework for risk stratification. However, rigorous prospective studies are necessary to validate its clinical utility and facilitate adoption.

Circulating Tumor HPV-DNA in the Management of HPV-Positive Oropharyngeal Carcinoma: A Systematic Review

PURPOSE

Blood-borne, cell-free DNA has been proposed as a means of individualizing the management of human papillomavirus (HPV)-positive oropharyngeal carcinoma.

METHODS AND MATERIALS

This study was designed based on the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) statement. A comprehensive literature search of peer-reviewed publications from January 2013 to January 2024 was undertaken to identify prospective studies pertaining to the use of circulating HPV-DNA for oropharyngeal carcinoma.

RESULTS

A total of 11 prospective studies were identified and differed in their clinical design, methods, and endpoints. Five included patients treated by chemoradiation; 3 by surgery; 2 by both; and 1 not specified. The timing and frequency of HPV-DNA draws was highly variable. The sample size ranged from 16 to 262 (mean, 99 patients).

CONCLUSIONS

While interest is growing with integrating circulating HPV-DNA into clinical practice, the supporting evidence is limited by the heterogeneity of the evidence.

ctDNA and Recurrence Risk for Adjuvant De-Escalation in HPV-Positive Oropharyngeal Carcinoma: A Secondary Analysis of the DART Phase 3 Randomized Clinical Trial

Importance

The De-escalated Adjuvant Radiation Therapy (DART) phase 3 randomized clinical trial (RCT) showed that in patients with human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma, postoperative minimal residual disease (MRD), detected through circulating tumor HPV DNA (ctHPVDNA), was associated with a higher risk of disease progression. When considered along with pathologic factors, postoperative ctHPVDNA assessment may improve patient selection for adjuvant treatment de-escalation; however, more data are needed to demonstrate how it may be used in personalizing treatment intensity.

Objective

To determine the association of postoperative MRD status with progression-free survival (PFS) after surgery for HPV-associated oropharyngeal squamous cell carcinoma.

Design, Setting, and Participants

This was a secondary analysis of the DART RCT, which was conducted from October 2016 to August 2020 in multiple sites in the US. Participants from the de-escalated adjuvant radiation therapy group and the standard of care group with available blood specimen data were included. Reports from 3-month posttreatment surveillance visits were used to assess associations and outcomes. Data analyses were performed from March 2023 to March of 2025.

Interventions

The DART group received 30 to 36 Gy of radiation therapy in 1.5 to 1.8 Gy twice daily, plus docetaxel, 15 mg/m2, on days 1 and 8. The standard of care group received 60 Gy with or without weekly cisplatin, 40 mg/m2.

Main Outcome and Measure

PFS.

Results

The analysis included 140 patients (mean [SD] age, 59.1 [8.4] years; 12 [8.6%] females and 128 [91.4%] males; 97 [69.3%] with no smoking history); characteristics were similar to the overall DART RCT population. Of these, 17 patients (12.1%) had postoperative MRD (13 of 96 [13.5%] receiving DART and 4 of 44 [9.1%] receiving standard of care). For all patients, postoperative MRD positivity was strongly associated with worsened PFS at 24 months (MRD positivity, 69.5%; MRD negativity, 95.9%; hazard ratio [HR], 0.19; 95% CI, 0.06-0.59). MRD positivity was associated with PFS when evaluating only those patients in the DART group, where 24-month PFS was 68.4% compared to 92.6% for MRD-negative patients (HR, 0.28; 95% CI, 0.08-0.93). Three months after completion of all treatment, 8 of 117 patients (6.8%) had detectable ctHPVDNA, whereas 109 of 117 (93.2%) did not, and detection was highly associated with PFS (HR, 20.48; 95% CI, 6.91-60.67).

Conclusions and Relevance

This secondary analysis of the DART RCT found that patients with detectable ctHPVDNA after surgery had a higher risk of disease progression. When added to the pathologic factors considered, ctHPVDNA assessment may improve selection of patients for treatment de-escalation. In addition, the 3-month posttreatment time point, early in surveillance, may identify a sizable portion of patients with progression and may guide intervention and surveillance after surgery for HPV-associated oropharyngeal squamous cell carcinoma.

Trial Registration

ClinicalTrials.gov Identifier: NCT02908477.

Postoperative ctHPVDNA Kinetics in Patients With HPV-Related Oropharyngeal Cancer

Importance

Circulating tumor human papillomavirus DNA (ctHPVDNA) is an important biomarker for the presence of HPV-associated oropharyngeal squamous cell carcinoma (OPSCC), but little is known about early postoperative kinetics of ctHPVDNA clearance.

Objective

To investigate early postoperative kinetics of ctHPVDNA in patients with HPV-associated OPSCC.

Design, Setting, and Participants

This prospective cohort study was conducted at a single tertiary care center from January 4, 2020, to January 26, 2023. Patients with newly diagnosed HPV-associated OPSCC undergoing surgical management were enrolled. HPV status was defined as positive if findings of p16 immunohistochemistry and/or HPV DNA in situ hybridization and/or E6/E7 RNA in situ hybridization were positive. Exclusion criteria included history of prior head and neck cancer and metastatic disease at presentation. Data were analyzed from September 1, 2024, to April 25, 2025.

Exposures

Transoral robotic surgery with concurrent neck dissection.

Main Outcomes and Measures

Blood was drawn prior to surgery (pretreatment), 1 to 2 days after surgery (postoperative days 1 to 2), and approximately 2 weeks after surgery (postoperative week 2; range, 8 to 20 days). ctHPVDNA was quantified by a tumor tissue-modified viral (TTMV) HPV DNA test. Correlations were tested between the pretreatment and postoperative day 1 to 2 TTMV HPV DNA levels using Gaussian regression. Concordance between detectability at postoperative day 1 to 2 and postoperative week 2 was explored using negative predictive value and positive predictive value.

Results

Of 57 included patients with detectable pretreatment TTMV HPV DNA, 51 (89%) were male, and the median (IQR) age was 59 (54-66) years. A total of 35 patients (61%) had blood draws at all 3 time points; 16 (28%) had detectable TTMV HPV DNA on postoperative day 1 to 2. Pretreatment and postoperative day 1 to 2 TTMV HPV DNA levels had a medium positive linear correlation (r = 0.31; 95% CI, 0.04-0.54). Undetectable TTMV HPV DNA on postoperative day 1 to 2 blood draw had a negative predictive value of 0.95 (95% CI, 0.74-1.00) for an undetectable level on postoperative week 2 blood draw, but a detectable level on postoperative day 1 to 2 blood draw only had a positive predictive value of 0.19 (95% CI, 0.04-0.46). Of the 16 patients with detectable TTMV HPV DNA pretreatment and at postoperative day 1 to 2, only 3 (19%) continued to have detectable TTMV HPV DNA at postoperative week 2. One patient had undetectable levels at postoperative day 1 to 2 and detectable levels at postoperative week 2.

Conclusions and Relevance

In this study, ctHPVDNA detectability early after surgery did not predict detectability at 2 weeks after surgery. ctHPVDNA clearance early after surgery could predict a negative test at 2 weeks. A negative blood draw finding on postoperative day 1 may be used to omit a postoperative blood draw at 2 weeks for minimal residual disease detection in future clinical trials.

Circulating tumor DNA in human papillomavirus-associated oropharyngeal cancer management: A systematic review

OBJECTIVE

Circulating tumor DNA (ctDNA) has emerged as a promising tool in the treatment of HPV-associated oropharyngeal squamous cell cancer (OPSCC). This systematic review sought to answer the question: what is the current role of ctDNA in the diagnosis, treatment, and surveillance of HPV-associated OPSCC?

DATA SOURCES

Medline (Ovid), Embase (Ovid), Scopus.

REVIEW METHODS

Original articles studying the role of ctDNA in the diagnosis or surveillance of HPV-associated OPSCC were eligible for inclusion. Two authors independently reviewed studies for inclusion and abstracted data, including study design, characterization of liquid biopsy technology, and diagnostic outcomes.

RESULTS

After a preliminary screening of 441 studies, 23 were selected for inclusion. Ten studies were conducted retrospectively, and 13 were conducted prospectively. In these studies, diagnostic testing included plasma-based droplet digital polymerase chain reaction (ddPCR, n = 13), quantitative PCR (qPCR, n = 4), digital PCR (dPCR, n = 3), next-generation sequencing (NGS) (n = 3), or a ctDNA detection kit (n = 1). Diagnostic outcomes were reported for pre-diagnosis (n = 1), pre-treatment (n = 17), during treatment (n = 6), and surveillance/recurrence (n = 11) timepoints. Test sensitivities ranged from 20.6 %-100 % pre-treatment and 72 %-100 % during surveillance, while test specificities ranged from 95 %-100 % pre-treatment and 87.2 %-100 % during surveillance.

CONCLUSION

The majority of studied ctDNA technologies allow for detection of HPV-associated OPSCC with high diagnostic accuracy. However, heterogeneity is introduced by test type and assay used. These findings highlight the utility, as well as limitations, of ctDNA in the diagnosis, treatment monitoring, and surveillance of HPV-associated OPSCC. Future studies and clinical consensus will need to address acceptable diagnostic accuracy thresholds for clinical use.

Circulating Tumour DNA as a Complementary Tool for Treatment Evaluation in HPV-Associated Head and Neck Squamous Cell Carcinoma: An Observational Cohort Study

OBJECTIVES

HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) and head and neck carcinoma of unknown primary (HNCUP) are increasing. Despite good prognosis, recurrence rates range from 10% to 25%. Surveillance with clinical controls and imaging is not always reliable. Circulating tumour human papillomavirus DNA (ctHPV-DNA) has emerged as a potential biomarker for treatment evaluation and detection of recurrence. We aimed to investigate the correlation between ctHPV-DNA in HPV+ OPSCC/HNCUP and radiologic tumour burden. Additionally, we sought to assess whether ctHPV-DNA could serve as a tool in treatment evaluation.

DESIGN

A prospective observational cohort study.

SETTING

This multicenter study involved three otolaryngology units located in central Sweden. We utilised HPV genotype-specific assays for droplet digital PCR (ddPCR) to detect ctHPV-DNA in plasma at diagnosis and follow-up. ctHPV-DNA levels were correlated to radiological tumour burden and radiological response using the Kendall Rank correlation coefficient and the Kruskal-Wallis test.

PARTICIPANTS

Patients with HPV+ OPSCC/HNCUP undergoing definitive (chemo)radiotherapy and enrolled in the CIRCOS study.

RESULTS

Out of 54 patients, 51 were eligible for analyses. At baseline, ctHPV-DNA was detectable in 88%. A majority of patients with a favourable radiological evaluation according to RECIST had a corresponding undetectable ctHPV-DNA at follow-up. The levels of ctHPV-DNA at baseline correlated with total tumour volume and nodal volume (rτ = 0.39, p < 0.01, respectively rτ = 0.26, p < 0.01).

CONCLUSION

ctHPV-DNA shows correlation with tumour burden. This study strengthens the role of ctHPV-DNA as a promising biomarker for treatment evaluation in HPV-related OPC/HNCUP. With further research on serial plasma sampling, ctHPV-DNA could complement radiological treatment evaluation in HPV+ OPSCC/HNCUP.

TRIAL REGISTRATION

NCT05904327 [ClinicalTrials.gov].

Association Between HPV Circulating Tumor DNA and Prognostic Inflammatory Indices in Oropharyngeal Squamous Cell Carcinoma: A Pilot Study

Circulating tumor DNA (ctDNA) has been developed as a marker of tumor burden in human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC). Inflammatory indices are also increasingly being used as prognostic surrogate markers in solid tumors, including head and neck cancers. The relationship between ctDNA levels and inflammatory indices has not been studied in HPV-associated OPSCC. We hypothesize that higher levels of inflammation are associated with higher ctDNA levels. Herein, we demonstrate an association between high pretreatment ctDNA levels and specific inflammatory indices, which may be lower-cost surrogate markers of high HPV ctDNA levels and may act as a surrogate marker for the body's immune response to HPV-positive OPSCC.

De-escalation of Adjuvant Therapy in Operatively Managed HPV Associated Oropharyngeal Carcinoma: Current Status and Future Directions

Human papillomavirus (HPV) associated oropharyngeal carcinoma is currently the most frequently diagnosed head and neck cancer in the United States. Due to the generally high cure rates with standard therapies, de-intensification strategies are being explored to reduce acute and long-term side effects. For patients treated with definitive chemoradiation, unselected de-escalation has shown worse progression-free survival compared to standard therapy. Concurrently, surgical management is becoming more prevalent, and adjuvant de-escalation appears promising. Further research is required to identify optimal candidacy for adjuvant de-escalation and to understand the relationship between dose and volume de-escalation. Biomarkers such as ctDNA may assist in candidate selection, but validation and alignment with pathological criteria are necessary.

Analytical Validation of NavDx+Gyn, a cfDNA-Based Fragmentomic Profiling Assay for HPV-Driven Gynecologic Cancers

Background/Objectives: The NavDx+Gyn blood test detects and quantifies fourteen HPV types in various sample types to provide a reliable means of detecting and monitoring HPV-driven gynecologic cancers. NavDx+Gyn is an extension of the NavDx assay, which identifies five high-risk HPV types. NavDx has been clinically validated in multiple independent studies for the surveillance of HPV-driven oropharyngeal cancer and has been integrated into clinical practice by over 1300 healthcare providers at over 500 medical sites in the US. The NavDx+Gyn assay incorporates an analysis of nine additional high-risk HPV types. Here, we report a detailed analytical validation of the NavDx+Gyn assay for use in cervical, vaginal, and vulvar cancer patients to detect fourteen high-risk HPV types related to HPV-driven gynecologic cancers. Methods: Parameters include specificity as measured by limits of blank (LoBs) and sensitivity illustrated via limits of detection and quantitation (LoDs and LoQs). Results: The LoBs were between 0 and 0.0926 copies/μL, LoDs were 0.1009 to 0.3147 copies/μL, and LoQs were 0.1009 to 0.3147 copies/μL, demonstrating the high analytic sensitivity and specificity provided by NavDx+Gyn. In-depth evaluations, including accuracy and intra- and inter-assay precision studies, were shown to be within acceptable ranges. Regression analysis revealed a high degree of correlation between expected and effective concentrations, demonstrating excellent linearity (R2 > 0.99) across a broad range of analyte concentrations. Conclusions: These results demonstrate that NavDx+Gyn accurately and reproducibly detects fourteen types of high-risk HPV, which aids in the diagnosis and surveillance of the vast majority of HPV-driven gynecologic cancers.

Redefining Candidates for Deintensification in Locoregionally Advanced P16+ Oropharyngeal Cancer Based on Relative Risk

PURPOSE

Randomized trials have found that patients with locoregionally advanced p16+ oropharyngeal squamous cell carcinoma (OPSCC) do not benefit from treatment deintensification, even among favorable risk groups. Although various methods have been used to identify candidates for treatment deintensification, the optimal approach is unknown.

METHODS AND MATERIALS

We conducted a multi-institutional cohort study of 444 patients with previously untreated p16+ OPSCC undergoing definitive radiation therapy with or without systemic therapy between 2009 and 2022. We compared the following 2 approaches for identifying candidates for deintensification: (1) favorable versus unfavorable risk, using NRG-HN005 eligibility criteria, and (2) low versus high relative risk of cancer events, using the Head and Neck Cancer Intergroup predictive classifier ("omega score"). We tested differences in outcomes and systemic therapy allocation by risk group using multivariable Cox models, competing event models, and logistic regression, and compared characteristics of hypothetical deintensification trials using the 2 approaches. Progression-free survival events were defined as cancer recurrence (locoregional or distant) or death from any cause.

RESULTS

Median follow-up time was 52 months; 120 patients (27.0%) were favorable risk; a different 120 patients had low omega score; 28 patients (6.3%) met both criteria; 184 patients (41.4%) had discordant classification. On ordinal logistic regression, decreasing omega score was associated with a statistically significantly lower odds of receiving intensive therapy (normalized odds ratio, 0.37 per SD; 95% CI, 0.24-0.57), with a greater magnitude than favorable risk group (odds ratio, 0.66; 95% CI, 0.44-0.99). Among patients receiving cisplatin and/or platinum-based induction (n = 374), favorable risk was associated with significantly improved progression-free survival (hazard ratio, 0.59; 95% CI, 0.36-0.99), whereas lower omega score was associated with a significantly decreased relative hazard for cancer events (relative hazard ratio, 0.18; 95% CI, 0.070-0.46). In simulations, selecting patients with low omega scores increased the efficiency of hypothetical noninferiority trials.

CONCLUSIONS

Considering patients' relative risk of cancer events can help define optimal populations for treatment deintensification in p16+ OPSCC.

Methodology of cfHPV-DNA Detection in Head and Neck Cancer: A Systematic Review and Meta-analysis

OBJECTIVE

We aim to compare the diagnostic accuracy of the different methodologies used in the detection of cell-free human papillomavirus (HPV) DNA in HPV-associated head and neck squamous cell carcinoma detection using bivariate analysis methods.

DATA SOURCES

Pubmed, Embase, and Scopus were queried using a broad search strategy to search for relevant studies.

REVIEW METHODS

Test characteristics were extracted from 33 studies following literature screening, and underwent analyses utilizing a bivariate approach. Summary statistics were identified for each type of methodology, and forest plots and summary receiver operating characteristic curves were constructed. Bias was estimated using Deek's Funnel Plot and the QUADAS-2 tool.

RESULTS

In terms of diagnostic accuracy, digital droplet polymerase chain reaction (ddPCR) based testing exhibited the highest diagnostics odds ratio at 138 (59.5, 318), followed closely by next-generation sequencing (NGS) at 120 (39.7, 362), then by polymerase chain reaction (PCR) at 31.4 (14.4, 68.6), and quantitative PCR at 8.74 (4.63, 16.5).

CONCLUSION

NGS and ddPCR are comparable in overall diagnostic accuracy, bringing into question their relative roles in diagnosis and screening. Cost-effective ddPCR assays may serve as useful diagnostic and screening tests in the clinic with their low false positive rates and high sensitivity. However, NGS assays also offer high sensitivity and companion metrics, suggesting they may have a more precise role in disease monitoring. Importantly, assay development and benchmarking need further standardization to improve comparison between assays. Finally, saliva-based testing needs to be further investigated using NGS and ddPCR to further understand its limitations in disease detection and monitoring.

Development and Validation of an Assay to Quantify Plasma Circulating Tumor Human Papillomavirus DNA for 13 High-Risk Types that Cause 98% of HPV-Positive Cancers

PURPOSE

Plasma circulating tumor HPV DNA (ctHPVDNA) persistence after curative-intent treatment may identify patients with HPV-positive cancers at risk for recurrence. Technical validation is required for use as an integral biomarker in a prospective clinical trial.

METHODS

Development and analytical validation of a digital droplet PCR assay for detection and quantification of 13 high-risk HPV types (i.e., Cell-Free 13) was performed with oligonucleotides/plasmids encoding type-specific E6/E7 coding regions. Clinical performance, determinants of detection/quantification, and associations of pre-treatment ctHPVDNA with progression-free survival (PFS) were also evaluated in a prospective cohort of 272 head and neck cancer patients.

RESULTS

Limit of detection, limit of quantification, and linear range of quantification were 5, 16 and 16-200,000 virus copies for all 13 high-risk HPV types. No cross-reactivity was detected across all 13 HPV types. At 10,000 copies, inter-assay coefficients of variation ranged from 0.3 to 4.6%. Multiplexing, DNA purification method, input plasma volume, total input cell-free (< 1800 ng) or genomic (< 700 ng) DNA did not affect HPV detection or quantification. The assay had a sensitivity of 91.7% (95%CI 87.3-94.9%) and specificity of 97.7% (95%CI 87.7-99.9%) for ctHPVDNA detection in the setting of newly diagnosed HPV-positive oropharyngeal cancer. Tumor and nodal stage categories, tumor viral load (ρ = 0.41, p < 0.05), and HPV integration status were associated with ctHPVDNA quantitative level. Pre-treatment ctHPVDNA greater than the median (231 copies/ml) was associated with worse PFS (HR = 2.14, 95%CI 1.16-3.97, p = 0.0156) in univariate analysis. However, this was no longer significant after adjustment for clinical covariates (HRadj = 1.81, 95%CI 0.97-3.37, p = 0.0635).

CONCLUSION

Cell-Free 13 demonstrated excellent analytical performance and clinical sensitivity/specificity in HPV-positive oropharyngeal cancer. Pre-treatment ctHPVDNA may be associated with oncologic outcomes.

Circulating tumor DNA determines induction chemotherapy response in HPV associated oropharyngeal squamous cell carcinoma: A pilot study

BACKGROUND

Induction chemotherapy (IC) followed by chemoradiation (CRT) is one treatment approach for patients with locoregionally advanced oropharyngeal squamous cell carcinoma (OPSCC) associated with human papillomavirus (HPV). This pilot study aimed to assess whether a circulating tumor (ct) DNA assay outperforms PET-CT in assessing treatment response in patients with HPV + OPSCC treated with induction chemotherapy (IC) followed by chemoradiation (CRT).

MATERIALS AND METHODS

Patients treated with IC and definitive CRT for HPV + OPSCC were included. HPV ctDNA and PET-CT were performed pre-treatment, 2-3 weeks after IC and 3 months after CRT. CtDNA levels were correlated with tumor volumes. Post-IC and post- CRT ctDNA levels were correlated post-induction and post-treatment imaging responses.

RESULTS

Seventeen patients were included. Baseline ctDNA levels correlated with volume of primary tumor (R2 = 0.33, p = 0.02), but did not correlate with nodal volumes (R2 = 0.01, p = 0.7) or total disease burden (R2 = 0.02, p = 0.6). After IC, 5.9 % (1/17) of patients had complete response by PET- CT, whereas 52.9 % (9/17) had complete molecular response by ctDNA testing. After completion of CRT, 76.5 % (13/17) patients had complete clinical response to treatment. Of patients who had ctDNA clearance after IC, 88.9 % (8/9) remained disease free after definitive CRT, whereas one had progressive disease diagnosed by both imaging and ctDNA. HPV ctDNA clearance after IC predicted disease control after CRT more strongly than PET-CT IC response (61.5 % (8/13) vs 7.7 % (1/13), p = 0.01).

CONCLUSIONS

HPV ctDNA clearance following IC outperforms standard imaging in assessing response and may help identify patients with favorable prognosis.

Highly-multiplex detection of plasma cell-free human papillomavirus-16 DNA in oropharyngeal carcinoma

BACKGROUND

Plasma cell-free Human Papillomavirus DNA (cfHPVDNA) is a biomarker for oropharyngeal carcinoma. Existing diagnostics may be limited by inadequate sensitivity or high cost/complexity for longitudinal monitoring.

OBJECTIVES

We hypothesized that sensitive and specific plasma cfHPVDNA detection may be achieved via a highly-multiplex qPCR method.

STUDY DESIGN

We designed and validated a single-tube one-step genotype-specific qPCR assay for detection of cfHPV16DNA in human plasma using >8,000 genomes spanning 18 genotypes. Amplicons were optimized for cfHPVDNA fragment size.

RESULTS

The cfHPV16DNA qPCR amplicons spanned 16 % of the HPV16 genome. Amplicons were conserved in a median of 99.0 % of 3,944 genomes in silico. The 95 % lower limit of detection was 0.35 genome copies/reaction and the limit of blank was 0. Multiplexing achieved a tenfold improvement in sensitivity compared with single amplicons using in silico simulations of cfHPVDNA fragmentation, which was in close agreement with experimental observations. An assay was replicated for HPV18 with similar observations. Among 36 patients with head/neck mucosal carcinomas (26 HPV-positive, 12 HPV-negative), there was 100 % concordance with tissue HPV status and with NavDx digital PCR. Pre-treatment specimens with sub-genomic cfHPVDNA concentration were detected. False negatives were observed with single amplicons but not with this multiplexed method. Among 17 patients with post-treatment landmark specimens, there was 100 % PPV and 100 % NPV for recurrence.

CONCLUSIONS

This assay is specific for plasma cfHPVDNA detection and prognostic for recurrence. Sub-genomic sensitivity was in close agreement with in silico simulations. The format might be more accessible than dPCR or NGS for longitudinal testing.

The clinical utility of circulating human papillomavirus across squamous cell carcinomas

BACKGROUND AND PURPOSE

The similarities in biology, treatment regimens and outcome between the different human papillomavirus (HPV) associated squamous cell carcinomas (SCCs) allow for extrapolation of results generated from one SC tumor type to another. In HPV associated cancers, HPV is integrated into the tumor genome and can consequently be detected in the circulating fragments of the tumor DNA. Thus, measurement of HPV in the plasma is a surrogate for circulating tumor DNA (ctDNA) and holds promise as a clinically relevant biomarker in HPV associated cancers. With the present overview we aim to present the status of circulating HPV studies in SCCs, the clinical potential and the gaps of knowledge, with the overall aim to facilitate the next steps into clinically relevant prospective trials.

MATERIAL AND METHODS

We reviewed the literature and presented the data for each tumor type as well as analyses of the clinical utility across the SCC.

RESULTS AND INTERPRETATION

A total of 41 studies were identified in cervical, head and neck and anal SCC and we discuss the common signals from the results across the different tumor sites. Our results not only confirm the strong clinical potential but also emphasize an urgent need to coordinate studies to allow for relevant sample sizes and statistical validations.

The effect of circulating tumor DNA on the prognosis of patients with head and neck squamous cell carcinoma: a systematic review and meta-analysis

BACKGROUND

Circulating tumour DNA (ctDNA) has emerged as a valuable liquid biopsy biomarker in the field of oncology, including head and neck squamous cell carcinomas (HNSCCs), offering potential insights into cancer diagnosis, progression, and prognosis. This review aims to comprehensively evaluate the utility of ctDNA as a prognostic biomarker in HNSCC.

METHODS

PubMed and Ovid were searched as part of our review. Studies that investigated the relationship between ctDNA and prognosis in HNSCC patients were included. Outcomes extracted included basic characteristics, ctDNA details and survival data. Meta-analysis was performed on eligible studies to determine pooled progression-free/recurrence-free survival (RFS/PFS) and overall survival (OS).

RESULTS

Twenty-two studies were included, involving 5062 HNSCC patients from 11 countries. The meta-analysis demonstrated that the positive ctDNA/methylation detection was associated with worse OS (HR = 2.00, 95% CI 1.35-2.96) and worse PFS/RFS (HR = 3.54, 95% CI 1.05-11.85). Positive ctEBV DNA was associated with poorer OS (HR = 2.86, 95% CI 1.84-4.45) and poorer PFS/RFS (HR = 1.93, 95% CI 1.74-2.13). Positive ctHPV DNA was associated with poorer OS (HR = 1.38, 95% CI 1.07-1.38) but not PFS/PFS (HR = 1.33, 95% CI 0.96-1.85).

CONCLUSION

Meta-analysis indicates that the status of ctDNA is significantly associated with the prognosis of HNSCC patients, with ctDNA/methylation-negative patients demonstrating better PFS/RFS and OS.

Circulating tumor tissue modified viral (TTMV)-HPV DNA in Recurrent, metastatic HPV-driven oropharyngeal cancer

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.

Sensitive and Specific Droplet Digital PCR Assays for Circulating Tumor HPV DNA: Development, Validation, and Clinical Application in HPV-Associated Cancers

BACKGROUND

Human papillomavirus (HPV) has emerged as a significant contributor to cancer incidence globally, particularly in the context of oropharyngeal squamous cell carcinoma (OPSCC) and cancer of unknown primary (HNCUP). This study aimed to develop and validate droplet digital PCR (ddPCR) assays for the detection of circulating tumor HPV DNA (ctHPV-DNA) in plasma, focusing on high-risk HPV genotypes associated with these cancers.

METHODS

ddPCR assays for HPV16, 18, 33, 35, 56, and 59 were developed and tested using gBlocks, HPV cell-free DNA, fragmented tumor HPV+ DNA, and plasma samples from patients with HPV+ OPSCC (n = 110) and HNCUP (n = 9).

RESULTS

Assays demonstrated robust technical sensitivity across all tested HPV genotypes. Clinical application of the assays on a cohort of patients with HPV+ OPSCC and HNCUP revealed high sensitivity (91.6%) and wide variability in ctHPV-DNA levels. Analyses revealed correlations between ctHPV-DNA levels and TNM stage and tumor viral load. The association between ctHPV-DNA and tumor viral load persisted even after adjusting for TNM stage. At posttreatment, 72.5% of samples had reached undetectable ctHPV-DNA levels. Having detectable ctHPV-DNA posttreatment was associated with a higher ctHPV-DNA level at diagnosis and higher viral load at diagnosis.

CONCLUSION

The findings underscore the potential of ctHPV-DNA as a biomarker for monitoring HPV+ cancers and offer insights into tumor dynamics. Implementation of these assays in clinical practice could enhance no-invasive treatment monitoring and recurrence detection in HPV-associated cancers.

CLINICAL TRIALS

NCT05904327.

Radiotherapy and Systemic Treatment for Leptomeningeal Disease

Leptomeningeal disease (LMD) is a devastating sequelae of metastatic spread that affects approximately 5% of cancer patients. The incidence of LMD is increasing due to advancements in systemic therapy and enhanced detection methods. The purpose of this review is to provide a detailed overview of the evidence in the detection, prognostication, and treatment of LMD. A comprehensive literature search of PUBMED was conducted to identify articles reporting on LMD including existing data and ongoing clinical trials. We found a wide array of treatment options available for LMD including chemotherapy, targeted agents, and immunotherapy as well as several choices for radiotherapy including whole brain radiotherapy (WBRT), stereotactic radiosurgery (SRS), and craniospinal irradiation (CSI). Despite treatment, the prognosis for patients with LMD is dismal, typically 2-4 months on average. Novel therapies and combination approaches are actively under investigation with the aim of improving outcomes and quality of life for patients with LMD. Recent prospective data on the use of proton CSI for patients with LMD have demonstrated its potential survival benefit with follow-up investigations underway. There is a need for validated metrics to predict prognosis and improve patient selection for patients with LMD in order to optimize treatment approaches.

The Next Chapter in Cancer Diagnostics: Advances in HPV-Positive Head and Neck Cancer

Human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC), particularly oropharyngeal squamous cell carcinoma (OPSCC), is an increasingly prevalent pathology worldwide, especially in developed countries. For diagnosing HPV in HNSCC, the combination of p16 immunohistochemistry (IHC) and polymerase chain reaction (PCR) offers high sensitivity and specificity, with p16 IHC being a reliable initial screen and PCR confirming HPV presence. Advanced techniques like next-generation sequencing (NGS) and RNA-based assays provide detailed insights but are primarily used in research settings. Regardless of HPV status, standard oncological treatments currently include surgery, radiation, and/or chemotherapy. This conventional approach does not account for the typically better prognosis of HPV-positive HNSCC patients, leading to increased chemo/radiation-induced secondary morbidities and reduced quality of life. Therefore, it is crucial to identify and detect HPV positivity and other molecular characteristics of HNSCC to personalize treatment strategies. This comprehensive review aims to summarize current knowledge on various HPV detection techniques and evaluate their advantages and disadvantages, with a focus on developing methodologies to identify new biomarkers in HPV-positive HNSCC. The review discusses direct and indirect HPV examination in tumor tissue, DNA- and RNA-based detection techniques, protein-based markers, liquid biopsy potentials, immune-related markers, epigenetic markers, novel biomarkers, and emerging technologies, providing an overall insight into the current state of knowledge.

The molecular characteristics of recurrent/metastatic HPV-positive head and neck squamous cell carcinoma: A systematic review of the literature

OBJECTIVES

About 17% of patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC), which is mainly comprised of oropharyngeal SCC (OPSCC), will experience disease recurrence, which is often considered incurable when manifested at a metastatic and/or recurrent stage. We conducted a critical qualitative systematic review. Our objectives were to provide an overview of the molecular landscape of recurrent/metastatic HPV-positive HNSCC as well as novel molecular biomarkers.

DESIGN

A literature review was conducted to identify studies reporting on the molecular characteristics of recurrent/metastatic HPV-positive HNSCC, novel molecular biomarkers and treatment options. The reviews of abstracts, full articles, and revision of the included studies, followed by data extraction and quality assessment were performed by three independent assessors. All primary literature, such as retrospective, prospective, and clinical trials as well as basic research studies were considered, and the final search was conducted at the end of February 2023. The level of evidence was rated using the guidelines published by the Oxford Centre for Evidence-based Medicine and quality was assessed using the Newcastle-Ottawa Scale criteria.

RESULTS AND CONCLUSIONS

The literature search resulted in the identification of 1991 articles. A total of 181 full articles were screened, and 66 articles were included in this analysis. Several studies reported that recurrent/metastatic HPV-positive HNSCC had higher rates of TP53 mutation and were genomically similar to HPV-negative HNSCC. The detection of circulating tumour tissue-modified HPV DNA (ctHPVDNA) as a specific biomarker has shown promising results for monitoring treatment response and recurrence in the subset of HPV-positive HNSCC. In addition, evidence for targeted therapy in recurrent/metastatic HPV-positive HNSCC has emerged, including agents that inhibit overexpressed EGFR. Studies of combination immunotherapy are also underway. Our review outlines the latest evidence on the distinct molecular profiles of recurrent/metastatic HPV-positive HNSCC as well as the clinical potential of ctHPVDNA testing in routine practice. More controlled and longitudinal studies are needed to identify additional molecular targets and to assess the performance and benefits of novel molecular biomarkers in clinical practice.

Addressing positive multi-cancer early detection tests in head and neck Surgery: Experience with head and neck work up for high-risk referrals

OBJECTIVES

Blood-based multi-cancer early detection (MCED) tests are now commercially available. However, there are currently no consensus guidelines available for head and neck cancer (HNC) providers to direct work up or surveillance for patients with a positive MCED test. We seek to describe cases of patients with positive MCED tests suggesting HNC and provide insights for their evaluation.

METHODS

Retrospective chart review of patients referred to Otolaryngology with an MCED result suggesting HNC. Patients enrolled in prospective MCED clinical trials were excluded. Cancer diagnoses were confirmed via frozen-section pathology.

RESULTS

Five patients were included (mean age: 69.2 years, range 50-87; 4 male) with MCED-identified-high-risk for HNC or lymphoma. Only patient was symptomatic. After physical exam and follow-up head and neck imaging, circulating tumor HPV DNA testing, two patients were diagnosed with p16 + oropharyngeal squamous cell carcinomas and underwent appropriate therapy. A third patient had no evidence of head and neck cancer but was diagnosed with sarcoma of the thigh. The remaining two patients had no evidence of malignancy after in-depth workup.

CONCLUSIONS

In this retrospective study, 2 of 5 patients referred to Otolaryngology with a positive MCED result were diagnosed with HPV + oropharyngeal squamous cell carcinoma. We recommend that positive HNC MCED work up include thorough head and neck examination with flexible laryngoscopy and focused CT or MRI imaging. Given the potential for inaccurate MCED tissue of origin classification, PET/CT may be useful in specific situations. For a patient with no cancer identified, development of clear guidelines is warranted.

Reappraisal of p16 for Determining HPV Status of Head and Neck Carcinomas Arising in HPV Hotspots

In an era of head and neck oncology where HPV status will soon dictate patient management, reliable HPV detection is critical. P16 immunohistochemistry (IHC) is currently recommended as the test of choice for oropharyngeal squamous cell carcinomas (OPSCCs). The purpose of this study was to determine the performance characteristics of p16 IHC based on a large clinical experience of squamous cell carcinomas (SCC) arising from HPV hot-spot regions of the head and neck. Consecutive OPSCCs, sinonasal SCCs, and metastatic SCCs of unknown primary sites were evaluated for the presence of HPV by p16 IHC and PCR-based HPV DNA testing as part of clinical care. For discrepant cases, high-risk HPV E6/E7 mRNA in situ hybridization (ISH) and, when possible, matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MassArray) genotyping were performed. 746 cancers underwent HPV testing by p16 IHC and DNA PCR genotyping. There was a 95.6% concordance between the 2 assays. Of the 33 discrepant cases, 32 cases (4.3%) were p16 positive but HPV DNA negative. In these cases, 68% were positive for mRNA ISH, invariably related to a non-16 HPV genotype. P16 IHC had an overall accuracy of 98.8%, a sensitivity of 99.8%, and a specificity of 92.1%. P16 IHC is a sensitive and specific assay for determining HPV status. HPV DNA PCR appears vulnerable to HPV genotype diversity and is prone to missing rare non-16 genotypes. HPV mRNA ISH is a practical and reliable direct measure of HPV that may help eliminate the small number of false-positive p16 cases and avoid potential patient harm related to erroneous HPV classification.

Human papillomavirus circulating tumor DNA: a diagnostic tool in squamous cell carcinoma of unknown primary-a pilot study

Introduction

Neck mass is the most common presentation of human papillomavirus-related (HPV-related) oropharyngeal squamous cell carcinoma (OPSCC). Recently, circulating tumor HPV-DNA (ctHPVDNA) assays have been developed to detect active OPSCC. This pilot study investigates the diagnostic accuracy of ctHPVDNA in establishing HPV status for known vs. unknown OPSCC presenting as a neck mass.

Methods

A single-institution pilot study was conducted on all patients with OPSCC presenting as a neck mass between 2021 and 2022. The diagnostic accuracy of ctHPVDNA was compared to that of standard diagnostic procedures used to obtain HPV status according to the American Society of Clinical Oncology (ASCO) guideline for squamous cell carcinoma of unknown primary (SCCUP). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ctHPVDNA were calculated.

Results

A total of 27 patients were included; 70.4% were current or former smokers, 48.1% (N = 13) had identifiable primaries, and 51.9% (N = 14) had SCCUP. Four patients with known primaries required operative direct laryngoscopy with biopsy (DLB) to establish HPV status. Two patients with SCCUP underwent diagnostic transoral robotic surgery (TORS) to establish HPV status and localize the primary. Twelve patients underwent therapeutic TORS and neck dissection. The gold standard for HPV status was based on final histopathologic p16 or HPV in situ hybridization (ISH) staining during workup/treatment. ctHPVDNA had 95.8% sensitivity, 100% specificity, 100% PPV, and 75% NPV in predicting HPV-positive OPSCC in the whole sample. Binary logistic regression model using ctHPVDNA results to predict HPV-positive OPSCC was significant (-2 log likelihood = 5.55, χ2 = 8.70, p <.01, Nagelkerke's R squared = .67). Among patients with identifiable primaries, all patients had HPV-positive tumors on final pathology, and ctHPVDNA was positive in 100%. In the unknown primary patients, ctHPVDNA had 90.9% sensitivity, 100% specificity, 100% PPV, and 75% NPV.

Discussion

ctHPVDNA demonstrated good diagnostic accuracy for both known and unknown primaries. Incorporation of ctHPVDNA into the diagnostic algorithm for SCCUP may reduce the need for multiple procedures to establish HPV status.

Sensitive MRD Detection from Lymphatic Fluid after Surgery in HPV-Associated Oropharyngeal Cancer

PURPOSE

Our goal was to demonstrate that lymphatic drainage fluid (lymph) has improved sensitivity in quantifying postoperative minimal residual disease (MRD) in locally advanced human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) compared with plasma, and leverage this novel biofluid for patient risk stratification.

EXPERIMENTAL DESIGN

We prospectively collected lymph samples from neck drains of 106 patients with HPV (+) OPSCC, along with 67 matched plasma samples, 24 hours after surgery. PCR and next-generation sequencing were used to quantify cancer-associated cell-free HPV (cf-HPV) and tumor-informed variants in lymph and plasma. Next, lymph cf-HPV and variants were compared with TNM stage, extranodal extension (ENE), and composite definitions of high-risk pathology. We then created a machine learning model, informed by lymph MRD and clinicopathologic features, to compare with progression-free survival (PFS).

RESULTS

Postoperative lymph was enriched with cf-HPV compared with plasma (P < 0.0001) and correlated with pN2 stage (P = 0.003), ENE (P < 0.0001), and trial-defined pathologic risk criteria (mean AUC = 0.78). In addition, the lymph mutation number and variant allele frequency were higher in pN2 ENE (+) necks than in pN1 ENE (+) (P = 0.03, P = 0.02) or pN0-N1 ENE (-) (P = 0.04, P = 0.03, respectively). The lymph MRD-informed risk model demonstrated inferior PFS in high-risk patients (AUC = 0.96, P < 0.0001).

CONCLUSIONS

Variant and cf-HPV quantification, performed in 24-hour postoperative lymph samples, reflects single- and multifeature high-risk pathologic criteria. Incorporating lymphatic MRD and clinicopathologic feature analysis can stratify PFS early after surgery in patients with HPV (+) head and neck cancer. See related commentary by Shannon and Iyer, p. 1223.

Unveiling Liquid Gold: Lymph as an HPV Marker in OPSCC to Guide Treatment Decisions

Distinguishing low- versus high-risk HPV-associated oropharyngeal squamous cell carcinoma (OPSCC) is pivotal for tailoring treatment. Liquid biopsy, measuring cell-free HPV-DNA in serum and saliva, assesses treatment response and early-recurrence risk. Postoperative lymphatic fluid may better guide future adjuvant therapy decisions due to its proximity to primary lesions and lymph nodes. See related article by Earland et al., p. 1409.

Circulating tumor HPV DNA assessments after surgery for human papilloma virus-associated oropharynx carcinoma

PURPOSE

To understand the utility of circulating tumor human papillomavirus DNA (ctHPVDNA) blood testing for HPV-associated oropharynx squamous cell carcinoma (HPV + OPSCC) after definitive surgery.

MATERIALS AND METHODS

Prospective cohort study of HPV(+)OPSCC patients with ctHPVDNA test data to assess its accuracy in detecting biopsy-confirmed disease at various post-treatment time points. Eligible patients had p16(+)/HPV(+) OPSCC and ctHPVDNA testing performed at any time pre-operatively and/or postoperatively. In cases of recurrence, patients were excluded from analysis if ctHPVDNA testing was not performed within 6 months of biopsy.

RESULTS

196 all-treatment-type patients had at least one PT ctHPVDNA test. The initial post-treatment (PT) ctHPVDNA sensitivity, specificity, PPV, and NPV were 69.2 % (9/13), 96.7 % (177/183), 60.0 % (9/15), and 97.8 % (177/181). 61 surgery alone (SA) patients underwent 128 PT tests. The initial PT SA ctHPVDNA sensitivity, specificity, PPV, and NPV were 100 % (2/2), 96.0 % (48/50), 50 % (2/4), and 100 % (48/48). 35 of 61 (57.4 %) SA patients had NCCN-based histopathologic indications for adjuvant (chemo)radiation but declined. 3 of 35 (8.57 %) had a positive PT ctHPVDNA test of which 1 of 3 (33 %) had biopsy-proven recurrence. Prospectively, ten patients had a PreT positive ctHPVDNA, underwent SA, refused adjuvant treatment, had an undetectable ctHPVDNA within 2 weeks of SA, and remained free of disease (mean 10.3 months).

CONCLUSION

The high specificity and NPV of ctHPVDNA after SA suggest ctHPVDNA may have a role in determining the omission of PT adjuvant (chemo)radiation in select patients.

Current and Emerging Diagnostic, Prognostic, and Predictive Biomarkers in Head and Neck Cancer

Head and neck cancers (HNC) are a biologically diverse set of cancers that are responsible for over 660,000 new diagnoses each year. Current therapies for HNC require a comprehensive, multimodal approach encompassing resection, radiation therapy, and systemic therapy. With an increased understanding of the mechanisms behind HNC, there has been growing interest in more accurate prognostic indicators of disease, effective post-treatment surveillance, and individualized treatments. This chapter will highlight the commonly used and studied biomarkers in head and neck squamous cell carcinoma.

Circulating Tumor HPV DNA for Surveillance of HPV-Positive Oropharyngeal Squamous Cell Carcinoma: A Narrative Review

Importance

Human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma has an overall favorable prognosis, yet a subset of patients will experience devastating disease recurrence. Current surveillance standards for detection of recurrent disease are imperfect. There is growing interest in improving detection of recurrent disease through the use of plasma-based assays able to detect circulating tumor HPV DNA.

Observations

Although most circulating tumor HPV DNA assays remain in the research domain, the circulating tumor tissue-modified viral HPV DNA assay became commercially available in the United States in early 2020 and has been increasingly used in the clinical setting. With the rapidly increasing incidence of HPV-positive oropharyngeal squamous cell carcinoma and concomitant expansion of biomarker capabilities for this disease, it is critical to reexamine current posttreatment surveillance practices and to determine whether emerging technologies may be used to improve outcomes for a growing survivor population. However, caution is advised; it is not yet known whether biomarker-based surveillance is truly beneficial, and as is true with any intervention, it has the capacity to cause harm.

Conclusions and Relevance

Using Margaret Pepe's classic 5 phases of biomarker development for early detection of cancer as a framework, this article reviews the current state of knowledge, highlights existing knowledge gaps, and suggests research that should be prioritized to understand the association between biomarker-based surveillance and patient outcomes. Specific attention is paid to the commercially available tumor tissue-modified viral HPV DNA assay, given its increasing clinical use. This review may serve as a road map for future research and a guide for clinicians considering its adoption in practice. Enrollment of patients into clinical trials incorporating biomarker-based surveillance should be prioritized.

Assessing the capacity of methylated DNA markers of cervical squamous cell carcinoma to discriminate oropharyngeal squamous cell carcinoma in human papillomavirus mediated disease

OBJECTIVE

Early identification of human papillomavirus associated oropharyngeal squamous cell carcinoma (HPV(+)OPSCC) is challenging and novel biomarkers are needed. We hypothesized that a panel of methylated DNA markers (MDMs) found in HPV(+) cervical squamous cell carcinoma (CSCC) will have similar discrimination in HPV(+)OPSCC tissues.

MATERIALS AND METHODS

Formalin-fixed, paraffin-embedded tissues were obtained from patients with primary HPV(+)OPSCC or HPV(+)CSCC; control tissues included normal oropharynx palatine tonsil (NOP) and cervix (NCS). Using a methylation-specific polymerase chain reaction, 21 previously validated cervical MDMs were evaluated on tissue-extracted DNA. Discrimination between case and control cervical and oropharynx tissue was assessed using area under the curve (AUC).

RESULTS

34 HPV(+)OPSCC, 36 HPV(+)CSCC, 26 NOP, and 24 NCS patients met inclusion criteria. Within HPV(+)CSCC, 18/21 (86%) of MDMs achieved an AUC ≥ 0.9 and all MDMs exhibited better than chance classifications relative to control cervical tissue (all p < 0.001). In contrast, within HPV(+)OPSCC only 5/21 (24%) MDMs achieved an AUC ≥ 0.90 but 19/21 (90%) exhibited better than chance classifications relative to control tonsil tissue (all p < 0.001). Overall, 13/21 MDMs had statistically significant lower AUCs in the oropharyngeal cohort compared to the cervical cohort, and only 1 MDM exhibited a statistically significant increase in AUC.

CONCLUSIONS

Previously validated MDMs exhibited robust performance in independent HPV(+)CSCC patients. However, most of these MDMs exhibited higher discrimination for HPV(+)CSCC than for HPV(+)OPSCC. This suggests that each SCC subtype requires a unique set of MDMs for optimal discrimination. Future studies are necessary to establish an MDM panel for HPV(+)OPSCC.

It is time to improve the diagnostic workup of oropharyngeal cancer with circulating tumor HPV DNA: Systematic review and meta-analysis

The possibility of detecting circulating tumor HPV DNA (ctHPVDNA) in plasma in patients with oropharyngeal cancer has been demonstrated in several reports. However, these data are from small cohorts and available tests for detection of ctHPVDNA are not fully validated. The aim is to evaluate sensitivity, specificity, and accuracy of ctHPVDNA by ddPCR to define its efficacy in the clinical setting for the diagnosis of HPV + OPSCC. A comprehensive search of three different databases: MEDLINE, Embase, and Cochrane Library databases. A total of 998 patients were evaluated from the 13 studies. OPSSC p16+ were 729, while controls p16- were 269. The meta-analytic study estimated the diagnostic performance of ctHPVDNA as follows: pooled sensitivity and specificity of 0.90 (95% CI: 0.82-0.94) and 0.94 (95% CI: 0.85-0.98), respectively; positive and negative likelihood ratios of 12.6 (95% CI: 4.9-32.1) and 0.05 (95% CI: 0.02-0.13), respectively. ddPCR for ctHPVDNA has good accuracy, sensitivity, and specificity for diagnosis of HPV + OPSCC. ctHPVDNA kinetic represents a great reliable opportunity to improve diagnostic and therapeutic management of cancer patients and could open new perspectives for understanding tumor biology.

Negative Predictive Value of Circulating Tumor Tissue Modified Viral (TTMV)-HPV DNA for HPV-driven Oropharyngeal Cancer Surveillance

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.

[ctHPV-DNA based precision oncology for patients with oropharyngeal cancer - Where are we?]

Human papillomavirus (HPV) is an established etiologic factor for cancers in the head and neck region, specifically for Oropharyngeal Squamous Cell Carcinoma (OPSCC). The comparatively good overall survival justifies the current discussion regarding therapy de-escalation for patients with a low-risk profile. In addition to the immunohistochemistry-based biomarker p16INK4a, there is still a need for diagnostic and prognostic biomarkers that allow risk stratification and monitoring during therapy and follow-up of these patients. In recent years, liquid biopsy, especially in the form of plasma samples, has gained importance and is already used to monitor viral DNA in patients with Epstein-Barr virus-associated nasopharyngeal carcinoma. Circulating DNA (ctDNA) released by the tumor into the bloodstream is particularly suitable for a high specificity in detecting virus-associated tumors. Detection of viral E6 and E7 oncogenes in HPV-positive OPSCC is predominantly performed by droplet digital/quantitative PCR as well as next generation sequencing. Detection of circulating HPV-DNA derived from tumor cells (ctHPV-DNA) at diagnosis is associated with advanced tumor stage, locoregional and distant metastases. Longitudinal studies have further demonstrated that detectable and/or increasing ctHPV-DNA levels are associated with treatment failure and disease relapse. However, a standardization of the diagnostic procedure is necessary before introducing liquid biopsy into the clinical routine. In the future, this might allow a valid reflection of disease progression in HPV-positive OPSCC.

High Specificity of HPV Cell-Free DNA Tests in Persons With HIV for the Detection of HPV-Related Cancer

INTRODUCTION

Persons with HIV (PWH) experience high rates of human papillomavirus (HPV)-associated cancers compared with the general population. Plasma HPV cell-free DNA (cfDNA) tests are sensitive in patients with known HPV-associated cancers. It is not known whether these tests can screen for invasive cancers in populations with high burdens of nonmalignant HPV disease such as PWH. It was not known whether HPV infection and/or noninvasive anal high-grade squamous intraepithelial lesions (HSIL) alone in this population would result in detectable HPV cfDNA, which would result in a high number of false positives if HPV cfDNA is used to screen for invasive cancers.

METHODS

We conducted a prospective study of PWH in 2 cohorts: 20 without anal HSIL and 20 with anal HSIL. We tested anal and vaginal swabs for HPV infection, and HPV genotyped the biopsies of anal HSIL. Finally, we performed HPV cfDNA droplet digital polymerase chain reaction to test for HPV16/18/33 from plasma samples.

RESULTS

In the combined cohorts, the median age was 56 years, 12.5% were cisgender women, and none had detectable HIV. In total, 84.6% had prevalent anovaginal HPV infection, including 10 participants with HPV16, 13 with HPV18, and 2 with HPV33 infections. Five and 2 participants had HPV16 and HPV33 detected in anal HSIL, respectively. Despite the high prevalence of HPV infection and anal HSIL, no participant had HPV16/18/33 detectable cfDNA by droplet digital polymerase chain reaction.

CONCLUSIONS

These results provide a strong rationale for investigating the use of HPV cfDNA in a screening setting for suspected HPV-related invasive cancers in PWH.

Predictive impact of human papillomavirus circulating tumor DNA in treatment response monitoring of HPV-associated cancers; a meta-analysis on recurrent event endpoints

BACKGROUND

HPV infection can cause cancer, and standard treatments often result in recurrence. The extent to which liquid biopsy using HPV circulating tumor DNA (HPV ctDNA) can be used as a promising marker for predicting recurrence in HPV-related cancers remains to be validated. Here we conducted a systematic review and meta-analysis to assess its effectiveness in predicting treatment response.

METHODS

We conducted a systematic literature search of online databases, including PubMed, Embase, Scopus, and the Cochrane Library, up to December 2022. The goal was to identify survival studies that evaluated the potential of plasma HPV ctDNA at baseline and end-of-treatment (EoT) in predicting recurrence of related cancers. Hazard ratios were estimated directly from models or extracted from Kaplan-Meier plots.

RESULTS

The pooled effect of HPV ctDNA presence on disease recurrence was estimated to be HR = 7.97 (95% CI: [3.74, 17.01]). Subgroup analysis showed that the risk of recurrence was HR = 2.17 (95% CI: [1.07, 4.41]) for baseline-positive cases and HR = 13.21 (95% CI: [6.62, 26.36]) for EoT-positive cases. Significant associations were also observed between recurrence of oropharyngeal squamous cell carcinoma (HR = 12.25 (95% CI: [2.62, 57.36])) and cervical cancer (HR = 4.60 (95% CI: [2.08, 10.17])) in plasma HPV ctDNA-positive patients.

CONCLUSIONS

The study found that HPV ctDNA detection can predict the rate of relapse or recurrence after treatment, with post-treatment measurement being more effective than baseline assessment. HPV ctDNA could be used as a surrogate or incorporated with other methods for detecting residual disease.

Peripheral surrogates of tumor burden to guide chemotherapeutic and immunotherapeutic strategies for HPV-associated malignancies

With the rapid adoption of immunotherapy into clinical practice for HPV-associated malignancies, assessing tumor burden using "liquid biopsies" would further our understanding of clinical outcomes mediated by immunotherapy and allow for tailoring of treatment based on real-time tumor dynamics. In this review, we examine translational studies on peripheral surrogates of tumor burden derived from peripheral blood in HPV-associated malignancies, including levels and methylation of circulating tumor DNA (ctDNA), miRNA derived from extracellular vesicles, circulating tumor cells (CTCs), and HPV-specific antibodies and T cell responses. We review their utility as prognostic and predictive biomarkers of response to chemotherapy and radiation, with a focus on how they may inform and guide immunotherapies to treat locally advanced and metastatic HPV-associated malignancies. We also highlight unanswered questions that must be addressed to translate and integrate these peripheral tumor biomarkers into the clinic.

The Clinical Utility of Circulating HPV DNA Biomarker in Oropharyngeal, Cervical, Anal, and Skin HPV-Related Cancers: A Review

Human papillomavirus (HPV) is recognized as being related to a wide variety of known cancers: cervical, oropharyngeal, anal, vaginal, penile, and skin. For some of these cancers, rigorous algorithms for screening, therapeutical interventions, and follow-up procedures have been established. Vaccination using the nonvalent anti-HPV vaccine, which prevents infection regarding the most frequently involved high-risk HPV types (16, 18, 31, 33, 45, 52, and 58) and low-risk HPV types (6 and 11), has also extensively prevented, controlled, and even eradicated HPV infections. Still, even with all of these multidisciplinary interventions, the burden of HPV cancers is still high worldwide. The circulating DNA of HPV-induced cancers is thought to be an adequate biomarker for optimizing the control of these virus-related cancers. We analyzed the literature published in the last 5 years regarding ctDNA and four of the above-mentioned cancers. The most frequently used assay for ctDNA detection was the droplet digital PCR assay, used for the management of therapy in the late stages of cancer. ctDNA could not be used for early detection in any of the studied cancers. The OPSCCs were the most frequent cancers analyzed via ctDNA assays. Larger, properly designed cohort studies might establish the clinical utility of this biomarker.

Circulating Tumor DNA in Human Papillomavirus-Mediated Oropharynx Cancer: Leveraging Early Data to Inform Future Directions

ABSTRACT

Circulating tumor DNA (ctDNA) has become an area of intense study in many solid malignancies including head and neck cancer. This is of particular interest for human papillomavirus-mediated oropharyngeal squamous cell carcinoma as this cohort of patients has excellent survival and is undergoing current clinical trials aimed at treatment de-escalation. Recent studies have demonstrated the prognostic implications of pretreatment ctDNA and the utility of monitoring ctDNA during and posttreatment; however, there is a need for a more critical understanding of ctDNA as it is beginning to be incorporated into clinical trials. This review discusses the current state of ctDNA in oropharynx cancer focusing on ctDNA kinetics and minimal residual disease detection and ends with a discussion of future applications.

Emerging Roles of Circulating Tumor DNA for Increased Precision and Personalization in Radiation Oncology

Recent breakthroughs in circulating tumor DNA (ctDNA) technologies present a compelling opportunity to combine this emerging liquid biopsy approach with the field of radiogenomics, the study of how tumor genomics correlate with radiotherapy response and radiotoxicity. Canonically, ctDNA levels reflect metastatic tumor burden, although newer ultrasensitive technologies can be used after curative-intent radiotherapy of localized disease to assess ctDNA for minimal residual disease (MRD) detection or for post-treatment surveillance. Furthermore, several studies have demonstrated the potential utility of ctDNA analysis across various cancer types managed with radiotherapy or chemoradiotherapy, including sarcoma and cancers of the head and neck, lung, colon, rectum, bladder, and prostate . Additionally, because peripheral blood mononuclear cells are routinely collected alongside ctDNA to filter out mutations associated with clonal hematopoiesis, these cells are also available for single nucleotide polymorphism analysis and could potentially be used to detect patients at high risk for radiotoxicity. Lastly, future ctDNA assays will be utilized to better assess locoregional MRD in order to more precisely guide adjuvant radiotherapy after surgery in cases of localized disease, and guide ablative radiotherapy in cases of oligometastatic disease.

Tumor-Derived Exosomes and the Role of Liquid Biopsy in Human Papillomavirus Oropharyngeal Squamous Cell Carcinoma

ABSTRACT

The global incidence of human papillomavirus-positive (HPV+) head and neck squamous cell carcinoma (HNSCC) has surged in recent decades, with HPV+ HNSCC accounting for >70% of oropharynx cancers in the United States. Its incidence in men has surpassed that of HPV+ cervical cancer in women, and reliable assays are needed for early detection and to monitor response to therapy. Human papillomavirus-positive OPSCC has a more favorable response to therapy and prognosis than HPV-negative (HPV-) HNSCC, motivating regimens to deintensify curative surgery or chemoradiotherapy protocols. A barrier to deintensifying and personalizing therapy is lack of reliable predictive biomarkers. Furthermore, HPV- HNSCC survival rates are static without reliable surveillance biomarkers available. The emergence of circulating plasma-based biomarkers reflecting the tumor-immune microenvironment heralds a new era in HNSCC diagnosis and therapy. We review evidence on tumor-derived extracellular vesicles (exosomes) as biomarkers for diagnosis, prognostication, and treatment in HPV+ and HPV- HNSCC.

The Current Role of Human Papillomavirus Circulating Tumor DNA in Oropharynx Cancer

ABSTRACT

Human papillomavirus infection is currently implicated in the majority of oropharyngeal squamous cell carcinoma cases diagnosed in the United States. Circulating tumor DNA (ctDNA) has emerged as a potential biomarker for human papillomavirus-related oropharyngeal squamous cell carcinoma and has the opportunity to improve the diagnosis, treatment, and surveillance of patients with this disease. Changes in ctDNA levels during and after primary therapy may be related to disease response, which can possibly have implications for treatment intensification or de-escalation strategies. Further, ctDNA seems to be sensitive and specific for disease recurrence and may improve upon current methods for assessing both treatment response and failure. In this review, we examine the relevant literature on the use of ctDNA for oropharyngeal cancer treatment and surveillance and discuss current limitations and future directions for this promising biomarker.

Liquid biopsy in head neck cancer: ready for clinical routine diagnostics?

PURPOSE OF REVIEW

The bodily fluids of patients with solid cancers representing a minimally-invasive source of clinically exploitable biomarkers have attracted an increasing amount of attention in recent years. In patients with head and neck squamous cell carcinoma (HNSCC), cell-free tumour DNA (ctDNA) belongs to the most promising liquid biomarkers for monitoring disease burden and identifying patients at high risk of recurrence. In this review, we highlight recent studies, evaluating the analytical validity and clinical utility of ctDNA as a dynamic biomarker in HNSCC, especially as it relates to risk stratification and contrasting human papilloma virus (HPV+ and HPV-) and carcinomas.

RECENT FINDINGS

The clinical potential of minimal residual disease monitoring through viral ctDNA in identifying HPV+ oropharyngeal carcinoma patients at higher risk of recurrence has recently been demonstrated. Furthermore, accumulating evidence supports a potential diagnostic value of ctDNA dynamics in HPV-negative HNSCC. Altogether, recent data suggest that ctDNA analysis may be a valuable tool in guiding (de)escalation of surgical interventions as well as adaptation in radiotherapy dosage, both in the definitive and adjuvant settings.

SUMMARY

Rigorous clinical trials with patient-relevant endpoints are critical in order to demonstrate that treatment decisions based on ctDNA dynamics result in better outcomes in HNSCC.

Circulating HPV DNA in HPV-associated cancers

Human papillomavirus (HPV) infections are the primary cause of almost all cervical cancers, anal cancers, and a variable proportion of other anogenital tumors, as well as head and neck cancers. Circulating HPV DNA (cHPV-DNA) is emerging as a biomarker with extensive potential in the management of HPV-driven malignancies. There has been a rapid advancement in the development of techniques for analyzing cHPV-DNA for the detection, characterization, and monitoring of HPV-associated cancers. As clinical evidence accumulates, it is becoming evident that cHPV-DNA can be used as a diagnostic tool. By conducting clinical trials assessing the clinical utility of cHPV-DNA, the full potential of cHPV-DNA for the screening, diagnosis, and treatment of HPV-related malignancies can be corroborated. In this review, we examine the current landscape of applications for cHPV-DNA liquid biopsies throughout the cancer care continuum, highlighting future opportunities for research and integration into clinical practice.

Analytical Validation of NavDx, a cfDNA-Based Fragmentomic Profiling Assay for HPV-Driven Cancers

The NavDx^® blood test analyzes tumor tissue modified viral (TTMV)-HPV DNA to provide a reliable means of detecting and monitoring HPV-driven cancers. The test has been clinically validated in a large number of independent studies and has been integrated into clinical practice by over 1000 healthcare providers at over 400 medical sites in the US. This Clinical Laboratory Improvement Amendments (CLIA), high complexity laboratory developed test, has also been accredited by the College of American Pathologists (CAP) and the New York State Department of Health. Here, we report a detailed analytical validation of the NavDx assay, including sample stability, specificity as measured by limits of blank (LOBs), and sensitivity illustrated via limits of detection and quantitation (LODs and LOQs). LOBs were 0-0.32 copies/μL, LODs were 0-1.10 copies/μL, and LOQs were <1.20-4.11 copies/μL, demonstrating the high sensitivity and specificity of data provided by NavDx. In-depth evaluations including accuracy and intra- and inter-assay precision studies were shown to be well within acceptable ranges. Regression analysis revealed a high degree of correlation between expected and effective concentrations, demonstrating excellent linearity (R² = 1) across a broad range of analyte concentrations. These results demonstrate that NavDx accurately and reproducibly detects circulating TTMV-HPV DNA, which has been shown to aid in the diagnosis and surveillance of HPV-driven cancers.

Association of Pretreatment Circulating Tumor Tissue-Modified Viral HPV DNA With Clinicopathologic Factors in HPV-Positive Oropharyngeal Cancer

Importance

Circulating tumor tissue-modified viral (TTMV) human papillomavirus (HPV) DNA is a dynamic, clinically relevant biomarker for HPV-positive oropharyngeal squamous cell carcinoma. Reasons for its wide pretreatment interpatient variability are not well understood.

Objective

To characterize clinicopathologic factors associated with TTMV HPV DNA.

Design, Setting, and Participants

This cross-sectional study included patients evaluated for HPV-positive oropharyngeal squamous cell carcinoma at Dana-Farber Cancer Institute in Boston, Massachusetts, between December 2019 and January 2022 and who were undergoing curative-intent treatment.

Exposures

Clinicopathologic characteristics including demographic variables, tumor and nodal staging, HPV genotype, and imaging findings.

Main Outcomes and Measures

Pretreatment circulating TTMV HPV DNA from 5 genotypes (16, 18, 31, 33, and 35) assessed using a commercially available digital droplet polymerase chain reaction-based assay, considered as either detectable/undetectable or a continuous score (fragments/mL).

Results

Among 110 included patients, 96 were men (87%) and 104 were White (95%), with a mean (SD) age of 62.2 (9.4) years. Circulating TTMV HPV DNA was detected in 98 patients (89%), with a median (IQR) score of 315 (47-2686) fragments/mL (range, 0-60 061 fragments/mL). Most detectable TTMV HPV DNA was genotype 16 (n = 86 [88%]), while 12 patients (12%) harbored other genotypes. Circulating TTMV HPV DNA detection was most strongly associated with clinical N stage. Although few patients had clinical stage N0 disease, only 4 of these 11 patients (36%) had detectable DNA compared with 94 of 99 patients (95%) with clinical stage N1 to N3 disease (proportion difference, 59%; 95% CI, 30%-87%). Among patients with undetectable TTMV HPV DNA, more than half (7 of 12 [58%]) had clinical stage N0 disease. The TTMV HPV DNA prevalence and score increased with progressively higher clinical nodal stage, diameter of largest lymph node, and higher nodal maximum standardized uptake value on positron emission tomography/computed tomography. In multivariable analysis, clinical nodal stage and nodal maximum standardized uptake value were each strongly associated with TTMV HPV DNA score. Among 27 surgically treated patients, more patients with than without lymphovascular invasion had detectable TTMV HPV DNA (12 of 12 [100%] vs 9 of 15 [60%]).

Conclusions and Relevance

In this cross-sectional study, circulating TTMV HPV DNA was statistically significantly associated with nodal disease at HPV-positive OPSCC diagnosis. The few patients with undetectable levels had predominantly clinical stage N0 disease, suggesting assay sensitivity for diagnostic purposes may be lower among patients without cervical lymphadenopathy. Mechanisms underlying this association, and the use of this biomarker for surveillance of patients with undetectable baseline values, warrant further investigation.

Circulating Human Papillomavirus DNA in Head and Neck Squamous Cell Carcinoma: Possible Applications and Future Directions

There has been a rising trend in HPV-induced head and neck cancers in the last several decades. This subgroup of squamous cell carcinoma is mostly located in the oropharynx and comprises a subset of patients who are typically younger and without the usual risk factors of smoking and alcohol use. As the prognosis of HPV-induced OPC is more favorable, there is a desire to properly select these patients for de-intensification protocols while identifying individuals who may suffer treatment failure. Here, we describe recent developments in circulating tumor HPV DNA as a marker of HPV-positive oropharyngeal cancer that can potentially be used as a diagnostic tool to stratify patients for de-escalation strategies and to survey for recurrence.