2844 - The Impact of Adverse Factors in Post-Operative HPV-Associated Oropharyngeal Cancers: An Analysis Using NCDB
Presenter(s)
A. Singh1,2, H. Rahman3, W. J. Talcott1, D. Frank4, B. A. Miles4, G. Har-El1, and B. Parashar1; 1Department of Radiation Medicine, Northwell Health, New Hyde Park, NY, 2Department of Chemistry and Biochemistry, University of California–Los Angeles, Los Angeles, CA, 3Office of Academic Affairs, Northwell Health, New York, NY, 4Department of Otolaryngology, Northwell Health, New York, NY
Purpose/Objective(s): Human Papilloma Virus (HPV) has been shown to be independently associated with improved oropharynx cancer (OPC) outcomes. This study aimed to assess if the presence of adverse factors modulated survival in a post-operative setting using the National Cancer Database (NCDB). We hypothesized that presence of adverse factors would not significantly dampen the apparent favorability of HPV-associated disease.
Materials/Methods: Oropharynx squamous cell carcinoma (ICD-O-3 8070/3) data from 2010-2017 was obtained. Cases with unknown HPV status, neoadjuvant therapy, no surgery, palliative endpoints, pediatric age, AJCC 8th ed staging, and metastasis (M1) were excluded. Stages I and II were grouped into “early stage” and stages III and IV were grouped into “advanced stage” as per the AJCC 7th ed. An “Adverse factor” included the presence of lymphovascular invasion or positive margin. Treatment groups were radiation only (RT), chemoradiation only (CRT), or no radiation nor chemo (No RT/CT). Data were stratified by HPV status and comparisons made across the presence/absence of adverse factors and treatment types. Kaplan-Meier estimates and Cox’s proportional hazard model for adjusted estimates are presented for survival data. Significance was set at p<.05.
Results: A total of 477 eligible patients had at least one adverse factor; among them, 279 were HPV-positive and 198 HPV-negative. Median survival (MS) of patients with adverse factors was 84.2 months (m) versus 146.6 m for those without adverse factors (p<0.0001). MS of HPV-negative patients with adverse factor was 39.3 m versus 145.6 m for similar HPV-positive cases (p<0.0001). In HPV-negative early-stage cases with adverse factors, five-year overall survival (5YS) was 29.9% with no RT versus 64.3% with RT (p=0.137). In HPV-positive, early-stage cases with adverse factors, 5YS was 60.3% with no RT, versus 69.3% with RT (p=0.282). In HPV-negative advanced cases with adverse factors, 5YS was 39.7% with CRT, versus 18.7% without CRT (p=<0.0001). In similar HPV-positive cases, 5YS was 74.6% with CRT versus 59.1% without CRT (p<0.001). A hazard of death ratio of 2.27 was observed for the presence of adverse factors versus none, when adjusted for HPV status, stage, treatment type, and age (95% CI:1.83-2.82, p<0.0001).
Conclusion: HPV-positivity improved survival overall compared to HPV-negative patients; however, the presence of adverse factors dampened survival in OPC patients regardless of HPV status. The hazard of death increases 2.27 times for patients with adverse factors when adjusted for HPV status, stage, treatment, and age. Adding CRT improved advanced-stage OS in both HPV-negative and HPV-positive patients. Limitations include retrospective bias and that NCDB is registry-based. Adverse factors should be independently investigated. Prospective evaluation is needed to assess treatment escalation/de-escalation in HPV-positive OPC in the presence of adverse factors.