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

Detection of Occult Recurrence Using Circulating Tumor Tissue Modified Viral HPV DNA among Patients Treated for HPV-Driven Oropharyngeal Carcinoma

PURPOSE

Despite generally favorable outcomes, 15% to 25% of patients with human papillomavirus (HPV)-driven oropharyngeal squamous cell carcinoma (OPSCC) will have recurrence. Current posttreatment surveillance practices rely on physical examinations and imaging and are inconsistently applied. We assessed circulating tumor tissue modified viral (TTMV)-HPV DNA obtained during routine posttreatment surveillance among a large population of real-world patients.

EXPERIMENTAL DESIGN

This retrospective clinical case series included 1,076 consecutive patients across 108 U.S. sites who were ≥ 3 months posttreatment for HPV-driven OPSCC and who had one or more TTMV-HPV DNA tests (NavDx, Naveris Laboratories) obtained during surveillance between February 6, 2020, and June 29, 2021. Test results were compared with subsequent clinical evaluations.

RESULTS

Circulating TTMV-HPV DNA was positive in 80 of 1,076 (7.4%) patients, with follow-up available on all. At first positive surveillance testing, 21 of 80 (26%) patients had known recurrence while 59 of 80 (74%) patients were not known to have recurrent disease. Among these 59 patients, 55 (93%) subsequently had a confirmed recurrence, 2 patients had clinically suspicious lesions, and 2 had clinically "no evidence of disease" (NED) at last follow-up. To date, the overall positive predictive value of TTMV-HPV DNA testing for recurrent disease is 95% (N = 76/80). In addition, the point-in-time negative predictive value is 95% (N = 1,198/1,256).

CONCLUSIONS

These findings highlight the clinical potential for circulating TTMV-HPV DNA testing in routine practice. As a surveillance tool, TTMV-HPV DNA positivity was the first indication of recurrence in the majority of cases, pre-dating identification by routine clinical and imaging exams. These data may inform future clinical and guideline-endorsed strategies for HPV-driven malignancy surveillance. See related commentary by Colevas, p. 4171.

The Sinai Robotic Surgery Trial in HPV-related oropharyngeal squamous cell carcinoma (SIRS 2.0 trial) – study protocol for a phase II non-randomized non-inferiority trial

Background

Human papillomavirus associated oropharyngeal squamous cell carcinoma (HPVOPSCC) usually affects a younger patient population. As such, the risk for long term toxicity associated with therapy is an important consideration. Multiple trials focused on de-escalation of therapy to preserve survival outcomes while minimizing treatment toxicity are currently in progress, however the question of which patients are ideal candidates for de-escalation remains unanswered. Circulating tumor DNA (cfHPVDNA) has emerged as a means of monitoring disease in patients with HPVOPSCC. Undetectable postoperative cfHPVDNA levels portend a better prognosis and by extension, may identify ideal candidates for de-escalation therapy. We propose an overview and rationale for a new institutional clinical trial protocol focusing on the use of cfHPVDNA to risk stratify patients for adjuvant therapy. We hypothesize that many surgical patients currently receiving radiation therapy may be clinically observed without adjuvant therapy.

Methods

Patients with measurable cfHPVDNA and clinically resectable HPVOPSCC will undergo TORS resection of tumors and neck dissection. Patients with undetectable cfHPVDNA at 3 weeks post-op will be allocated to low or high-risk treatment protocol groups. The low risk group consists of patients with <4 positive lymph nodes, ≤2 mm extranodal extension (ENE), and perineural invasion (PNI) or lymphovascular invasion (LVI) alone. The high-risk group is made up of patients with ≥4 positive lymph nodes, gross ENE, positive margins, N2c disease and/or the combination of both PNI and LVI. The low-risk group will be allocated to an observation arm, while the high-risk group will receive 46 Gy of adjuvant radiotherapy and weekly cisplatin therapy. The primary outcome of interest is 2-year disease recurrence with secondary outcomes of 2-year disease free survival, locoregional control, overall survival, and quality of life measures. A sample of 126 patients in the low-risk group and 73 patients in the high-risk group will be required to evaluate non-inferiority to the standard of care.

Discussion

This study will provide much needed recurrence and survival data for patients that undergo primary TORS followed by observation or de-escalated adjuvant therapy. Additionally, it will help delineate the role of cfHPVDNA in the risk stratification of patients that undergo treatment de-intensification.

The Promise of Circulating Tumor DNA in Head and Neck Cancer

As the seventh most common cancer globally, head and neck cancers (HNC) exert considerable disease burden, with an estimated 277,597 deaths worldwide in 2020 alone. Traditional risk factors for HNC include tobacco, alcohol, and betel nut; more recently, human papillomavirus has emerged as a distinct driver of disease. Currently, limitations of cancer screening and surveillance methods often lead to identifying HNC in more advanced stages, with associated poor outcomes. Liquid biopsies, in particular circulating tumor DNA (ctDNA), offer the potential for enhancing screening, early diagnosis, and surveillance in HNC patients, with potential improvements in HNC patient outcomes. In this review, we examine current methodologies for detecting ctDNA and highlight current research illustrating viral and non-viral ctDNA biomarker utilities in HNC screening, diagnosis, treatment response, and prognosis. We also summarize current challenges and future directions for ctDNA testing in HNC patients.