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FOR HEALTHCARE PROVIDERS TREATING HPV+ CANCER

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A Note to Providers.

The following guidance is informed by the consensus recommendations of the California Head and Neck Consortium (CHNC), published in the Journal of Clinical Oncology Oncology Practice (JCO OP) in December 2025. The panel comprised 33 experts across 15 institutions using a hybrid Delphi methodology. Consensus levels are noted where relevant.11

When to Begin NavDx® Testing.

A pre-treatment baseline TTMV Score is not required to begin NavDx testing during surveillance, but obtaining one is recommended when possible. A confirmed pre-treatment test supports more meaningful interpretation of post-treatment results and may help identify patients whose disease did not respond fully to treatment. (81.8% consensus, CHNC 2025) 11

Expert consensus supports beginning NavDx testing for surveillance monitoring at 3 months post-treatment (usually the first scheduled surveillance visit after completion of definitive therapy). (84.8% consensus, CHNC 2025) 11

Points to Remember:

NavDx testing can begin at any point in the patient’s care journey.

The absence of a baseline NavDx result does not preclude the clinical value of serial post-treatment testing or testing during treatment. The positive predictive value of the NavDx test in surveillance is independent of a baseline test value. Consistent negative results during surveillance after a positive test at any point in the journey, or consistently declining positive results during treatment, provide meaningful reassurance regardless of whether a baseline was established.

NavDx testing supplements, but does not replace, standard clinical surveillance.

Physical exam, nasopharyngeal endoscopy, and imaging remain part of appropriate HPV-driven OPSCC care. NavDx testing adds a layer of objective, molecular information that these tools cannot provide on their own, while the other tools provide insight into patient healing, function, and when needed, localization of disease recurrence indicated by a positive NavDx test.

The NavDx test can be ordered and performed any time prior to initial biopsy or resection or the initiation of CRT or immunotherapy.

Recommended Testing Cadence.

The CHNC recommendations aligning NavDx testing with routine surveillance visits (87.9% consensus).11 Medicare covers NavDx testing for OPSCC surveillance at the following intervals:

Interpreting Results and Clinical Decision Support.

The NavDx test report provides a TTMV-HPV DNA status (detected / not detected) and a quantitative TTMV Score. The following framework provides guidance for clinical decision-making based on test results.

When the Result Is Negative

(TTMV-HPV DNA Not Detected)

A negative TTMV Score is associated with an NPV of ≥98% in OPSCC surveillance populations.2 That means the vast majority of patients with a negative result have no detectable molecular evidence of disease at the time of testing. Consistently negative results over time are associated with significantly better recurrence-free and overall survival.

  • Continue routine surveillance at the recommended cadence
  • A negative result does not eliminate the need for regular surveillance visits, clinical exam, nasopharyngeal endoscopy, and imaging
When the Result Is Positive

(TTMV-HPV DNA Detected)

A positive TTMV Score has a PPV of ≥95% in OPSCC surveillance populations.2,3 That means a positive result is strongly associated with recurrent disease. In many cases, NavDx testing may detect recurrence before it is visible on imaging or produces symptoms. The CHNC has established a clear workflow for managing a positive result in the absence of clinical evidence of disease:

  1. Accelerate clinical exam and imaging. Do not wait for the next scheduled surveillance visit. Order appropriate imaging (CT or PET/CT depending on clinical context). (81.8% consensus, CHNC 2025)11
  2. If imaging is negative, retest in 1 month. A single positive result necessitates close follow-up. If no clinical evidence of disease is found, the expert-endorsed next step is a repeat NavDx test in 1 month. (90.9% agreement).11
  3. If the NavDx test is positive again at 1 month and there is still no clinical evidence of disease, intensify imaging surveillance and expand the field of view. Persistent TTMV positivity is clinically meaningful. More aggressive imaging (e.g., PET/CT, if CT was first-line) is appropriate and expert-endorsed. (93.9% consensus). 11
When the Result Is Indeterminate

(TTMV-HPV DNA Status Unconfirmed)

Indeterminate NavDx results occur in fewer than 1.5% of tests in real-world daily practice.10 An indeterminate result should not be interpreted as positive or negative. However, it should be taken seriously: Indeterminate findings have been associated with a high rate of conversion. Approximately 50% convert to positive on the subsequent test, often accompanied by clinical evidence of active disease.10

  • Repeat testing in 4–6 weeks
  • Continue routine clinical surveillance in the interim

Managing Patient Expectations Around a Positive Result.

The CHNC consensus notes that a positive ctHPVDNA result without clinical or radiographic evidence of disease can increase patient distress (81.8% consensus). Proactive communication about what a positive result means and what the next steps are can help patients manage anxiety while appropriate follow-up is completed. See Implementing NavDx in the Clinic for patient communication guidance.

NavDx at Each Stage of Care.

NavDx testing can be used across the full care continuum. Select a use case below for detailed clinical guidance.

Pre-Treatment

  • Confirm HPV+ etiology
  • Identify the tumor HPV genotype
View Pre-Treatment Guidance

During Treatment

  • TTMV-HPV DNA clearance kinetics during CRT
  • Identify molecular residual disease
View During Treatment Guidance

Surveillance

The most common use of NavDx testing

  • Detect recurrence earlier with high-confidence positive results
  • Provide reassurance with high-confidence negative results
View Surveillance Guidance

A pre-treatment test is not required to use the NavDx test at other points in the care journey. Monitoring with the NavDx test can be started at any time.

A Note to Providers.

Formal expert consensus guidelines for NavDx® use in ASCC surveillance have not yet been published. The guidance below reflects Medicare coverage policy, published clinical evidence, and best practices from the treating community. As the ASCC evidence base continues to grow, this guidance will be updated to reflect emerging recommendations.

When to Begin NavDx Testing.

A pre-treatment baseline TTMV Score is not required to begin testing during treatment or during surveillance, but obtaining one is recommended when feasible. In the foundational ASCC validation study, NavDx detected TTMV-HPV DNA in 85% of patients at their pre-treatment draw, confirming that a reliable baseline is achievable for most ASCC patients.4

Critically for ASCC, post-chemoradiotherapy (CRT) imaging is typically delayed until approximately 26 weeks post-treatment due to treatment-related inflammation, fibrosis, and tissue changes that make earlier imaging unreliable. NavDx testing can provide molecular surveillance during this window, offering the only objective disease-status information available in the months immediately following treatment completion. Serial testing can provide insight into whether the tumor is regressing, stable, or progressing during this 6-month window.

Points to Remember:

NavDx testing can begin at any point in the patient’s care journey.

The absence of a baseline NavDx result does not preclude the clinical value of serial post-treatment testing or testing during treatment. The positive predictive value of the NavDx test in surveillance is independent of a baseline test value. Consistent negative results during surveillance after a positive test at any point in the journey, or consistently declining positive results during treatment, provide meaningful reassurance regardless of whether a baseline was established.

NavDx testing supplements, but does not replace, standard clinical surveillance.

Digital anorectal exam (DARE), anoscopy, and imaging remain part of appropriate HPV-driven ASCC care. NavDx testing adds a layer of objective, molecular information that these tools cannot provide on their own.

If you choose to order the NavDx test pre-treatment, it can be done anytime prior to the initiation of treatment.

Because anal cancer primaries may be small, the NavDx test is best performed before biopsy, as the lesion may be removed by biopsy, potentially causing a false negative result. For patients with larger lesions, NavDx testing 2-3 days after biopsy procedure will provide the most accurate pre-treatment ctHPVDNA level, allowing for clearance of procedure-related ctHPVDNA.

Recommended Testing Cadence.

In the absence of published consensus guidelines for ASCC, the Medicare coverage cadence provides the practical clinical benchmark for NavDx testing frequency in ASCC surveillance:

Interpreting Results and Clinical Decision Support.

The NavDx test report provides a TTMV-HPV DNA status (detected / not detected) and a quantitative TTMV Score. The following framework provides guidance for clinical decision-making based on test results.

When the Result Is Negative

(TTMV-HPV DNA Not Detected)

In the ASCC validation study, NavDx testing had a per-patient NPV of 92.5%.4 Patients with consistently negative post-treatment NavDx results had significantly better recurrence-free survival than those who tested positive at any point.4

  • Continue routine surveillance at the recommended cadence
  • A negative result does not eliminate the need for clinical exam, DARE, or imaging per NCCN guidelines
When the Result Is Positive

(TTMV-HPV DNA Detected)

The per-patient PPV of NavDx testing in ASCC surveillance populations is 96.0%.4 A positive result in an asymptomatic patient warrants prompt follow-up.

  • Accelerate clinical exam and imaging; retest in 1 month if imaging shows no evidence of disease
  • If follow-up NavDx testing is positive, consider escalating imaging (e.g., PET/CT if initial imaging used CT only). Coordinate with your multidisciplinary team as appropriate.
When the Result Is Indeterminate

(TTMV-HPV DNA Status Unconfirmed)

The NavDx indeterminate rate in ASCC post-treatment testing is approximately 1.9% in published research4 and fewer than 1.5% in real-world daily practice.10 An indeterminate result should not be interpreted as positive or negative. However, it should be taken seriously: Across both OPSCC and ASCC, NavDx indeterminate findings have been associated with a high rate of conversion. Approximately 50% convert to positive on the subsequent test, often accompanied by clinical evidence of active disease.10

  • Repeat testing in 4–6 weeks
  • Continue routine clinical surveillance in the interim.

Managing Patient Expectations Around a Positive Result.

A positive NavDx result without clinical or radiographic evidence of disease can increase patient anxiety. Proactive communication about what a positive result means and what the next steps are can help patients manage anxiety while appropriate follow-up is completed. See Implementing NavDx in the Clinic for patient communication guidance.

NavDx at Each Stage of Care.

NavDx testing can be used across the full care continuum in ASCC. Select a use case below for detailed clinical guidance.

Pre-Treatment

  • Confirm HPV+ etiology
  • Identify the tumor HPV genotype
View Pre-Treatment Guidance

During Treatment

  • TTMV-HPV DNA clearance kinetics during CRT
  • Identify molecular residual disease
View During Treatment Guidance

Surveillance

The most common use of NavDx testing

  • Detect recurrence earlier with high-confidence positive results
  • Provide reassurance with high-confidence negative results
View Surveillance Guidance

A pre-treatment test is not required to use the NavDx test at other points in the care journey. Monitoring with the NavDx test can be started at any time.

References

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  10. Naveris data on file.  
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