Efficacy of TTMV HPV DNA testing for surveillance in HPV + head and neck cancer.

Abstract

e18056 Background: This is a retrospective study of tumor-modified HPV DNA (TTMV) as a tool for post-treatment surveillance in patients with HPV+ head and neck squamous cancer (HPV+HNC). HPV+HNC, has a better prognosis and lower recurrence rates than smoking and alcohol-related cancers. Approximately 80% of recurrences occur within the first 2 years post-treatment. Early identification of recurrence is likely to improve the outcomes of salvage therapies in this disease. TTMV is a sensitive and specific biomarker for HPV+HNC. This study aims to inform best practices for TTMV use in surveillance to enhance early recurrence detection and timely intervention. Methods: The study analyzed 54 HPV+HNC patients treated for cure with induction chemotherapy or chemoimmunotherapy (IC) followed by chemoradiotherapy (CRT) (30 patients) or CRT alone (24 patients). All patients were confirmed HPV+ by molecular pathology and had a +TTMV prior to treatment. TTMV was performed during and after treatment; routine follow-up assessments were done using physical exam (PE), imaging (PET), and biopsy (bx). TTMV results were compared to traditional surveillance methods for prediction of recurrence. Results: Post-treatment TTMV status: 53 out of 54 patients had an initial -TTMV post-treatment. Recurrence detection: With a mean follow-up of 25 months (3.5–51 mo). 12 out of 54 patients showed signs of recurrence or persistent disease, identified by +TTMV, imaging, symptoms, and/or PE. Specifically: Group 1: 4/12 patients had positive imaging, symptoms and/or PE and -TTMV. All 4 patients remain disease-free (NED) after further investigation, a median of 23.5 months (4-34 mo) post findings. Group 2: 7/12 patients had a + post treatment TTMV with a median of 3 months (1-9 mo) from treatment end. 6 /7 (87.5%) had confirmed HPV+ disease via biopsy . 3/7 (43%) patients with + post-treatment TTMV had initial positive imaging. 4/7 (57%) with +TTMV and negative initial imaging developed positive imaging with amedian time of 3 months (2-11 mo) after +TTMV. One patient with a positive PET scan 11 months after the first +TTMV has a biopsy pending. Group 3: 1/12 (8.33%) patient with a -TTMV developed HPV+ metastases by + PET and + bx 9 months post therapy. Conclusions: A positive TTMV post-treatment was 100% predictive of recurrence, demonstrating its strong utility in early detection. TTMV can guide the timing of imaging as TTMV + recurrence may not be immediately detectable on scans. TTMV kinetics can be used alongside PE and imaging to improve surveillance accuracy. While TTMV cannot replace imaging, due to its inability to confirm disease location or burden, it can help guide decision-making which is especially useful when interpreting complex post-treatment changes in the head and neck region.TTMV could be efficiently incorporated into surveillance guidelines for HPV+ HNC, as a complementary tool for detecting recurrence and justifying imaging in resource-limited settings.