Oropharyngeal cancer has emerged in the last three decades as an important HPV-associated head and neck cancer and is projected to surpass cervical cancer as the dominant HPV-related cancer in the United States by 2020. While it is generally confers survival advantage compared to non-HPV related head and neck cancer, there is limited data on the trends in oropharyngeal cancer survival since the recognition of the role of HPV in head and neck cancer. The objective of the study was to describe trends in relative survival of oropharyngeal cancer in the United States in the last three decades.
Patients diagnosed with index oropharyngeal cancer between 1975 and 2009 were abstracted from the Surveillance, Epidemiology, and End Results (SEER) 9 database to determine their 5-year relative survival percentage. Joinpoint regression analyses determined annual percent change (APC) trends in 5-year survival by year of diagnosis stratified by race, sex, and age. APCs were conducted at an alpha of 0.05 and were two-tailed.
There were 25,034 patients with oropharyngeal cancer included in the analyses. Seventy-three percent (73%) of participants were male, and 83% were white. Overall, relative survival from oropharyngeal cancer increased from 33% in 1975 to 68% in 2009, yielding 106% increase in survival over the 35-year period of the study. Specifically, relative survival increased from 1975-1988 (APC=1.34, p <.05) and then more sharply increased from 1988-2009 (APC=2.67, p <.05). Both blacks and whites exhibited steady relative survival increases from 1975-2009, however whites had overall higher survival rate increase than blacks (whites APC=2.31, blacks APC=2.17, p <.05). Comparing males vs. females, relative survival among males and females also increased over the study period with males having an overall better survival than females (females APC=1.21, males APC=3.76, p <.05). This better survival rates among males was largely due to the sharp increase in survival among males from 1991-2003 (APC=3.76, p <.05). After 2000, males tended to have better survival than females. There was also increase in survival across age-groups (20-44, 45-64, and 65+ years), with a marked recent increase among 65+ years (2001-2009 APC=4.27, p <.05). However, the 20-44 year group had the best survival rates as expected.
Our study show that there has been significant increases in oropharyngeal cancer relative survival from 1975-2009 across races, sexes, and ages. Patients diagnosed at younger ages had better survival compared to older patients. The fact that whites had better overall survival rates than blacks may point to the existing health disparities issues in the United States.