Temporal Trends in Oropharyngeal Cancer Incidence, Survival, and Cancer-Directed Surgery Among Elderly Americans

Abstract

<h3>Purpose/Objective(s)</h3> Elderly cancer patients are a growing demographic group that is unique in a myriad of ways which may impact cancer diagnosis, treatment, and survival. This study aims to compare HPV-associated oropharyngeal sites to other mucosal head and neck cancer (HNC) sites on incidence, cancer-specific mortality, and cancer-directed surgery trends in elderly Americans (age ≥85). <h3>Materials/Methods</h3> Using data from the Surveillance, Epidemiology, and End Results (SEER) database, incidence and two-year HNC specific mortality trends from 2000-2018 in Americans ≥85 years were assessed using joint-point analysis and compared between the oropharynx and other HNC sites. Trends were quantified as annual percentage change (APC) for incidence and surgical treatment, and biannually (BPC) for 2-year HNC-specific mortality. Precision was reported with 95% confidence intervals (CI). <h3>Results</h3> Among those age ≥85 years, oropharyngeal cancer (OPC) incidence increased (APC 1.48%, [95% CI: 0.59 - 2.37]) while mortality decreased (BPC 3.27% [95% CI: -6.20 – -0.26]) from 2000-2018. At all other HNC sites, the incidence and mortality remained stable. OPC specific mortality approached other sites, decreasing from 60% in 2000 to 45% in 2018. For oropharyngeal tumors, decreases were observed for recommendation for surgery (APC = -4.10%; [95% CI: -5.11 – -3.08]) and surgical treatment (APC = -1.76% [95% CI: -3.05 – -0.45]). Similar but less pronounced trends were seen at all HNC sites collectively where the percentage of patients receiving surgery decreased -0.80% [95% CI: -1.09 – -0.52] annually, and the percentage for whom surgery was recommended decreased -5.40% [95% CI: -7.62 – -3.14] from 2000-2004, and -1.01% [95% CI: -1.40 – -0.61] from 2004-2018. <h3>Conclusion</h3> As noted previously in younger cohorts, we found that OPC incidence has increased among the eldest Americans (age≥85). This is likely due to a known birth cohort from the early half of the 20^th century at high risk of developing HPV-associated cancers aging into this demographic category. An increasing proportion of HPV-positive tumors, with associated improved prognosis, would account for the observed survival improvement at this site. Our analysis also suggests that HNC providers and patients may have moved towards non-surgical therapy in this age group possibly due to concern for higher surgical risk in this cohort or due to the radiosensitivity of HPV-positive tumors of the oropharynx specifically. These data suggest the changing treatment approach has not been detrimental to survival outcomes. However, establishing optimal treatment requires clinical trials which often exclude this age cohort. Future studies with known HPV-status are needed to definitively understand the geriatric oropharyngeal cancer burden.