Racial Disparities in Oropharyngeal Cancer Stage at Diagnosis

Discussion

The results of the present study show that race is associated with advanced disease presentation in oropharyngeal cancer. Black race was associated with increased risk of presenting with Stage III or IV disease, T3 or T4 tumors, distant metastasis, and unresectable tumor. Although univariable analysis suggested that black race was associated with decreased risk of presenting with nodal metastasis, this was not significant on multivariable analysis.

Only few studies have examined racial disparities in oropharyngeal cancer. Weatherspoon et al. examined oral cavity and oropharyngeal cancer incidence trends and disparities, using the SEER database (9). They found that whites had a higher incidence risk compared to all other race/ethnicity groups. Zandberg et al. assessed racial disparities in 1,318 patients with oral cavity, oropharyngeal, hypopharyngeal, or laryngeal tumors treated at their institution (7). Similar to our study, they found that black patients had increased risk of presenting with locally advanced tumors.

To our knowledge, this is the first study to evaluate racial disparities in disease stage at diagnosis in oropharyngeal cancer patients. Our study shows that not only do black patients have increased risk of presenting with advanced disease, they are also more likely to present with potentially incurable disease. This is significant because this higher propensity to present with incurable disease may partially account for the racial disparities observed in head and neck cancer survival, even after adjusting for AJCC stage group. There are several potential explanations for the racial differences in advanced stage at diagnosis observed in our study. African Americans are more likely to be socioeconomically disadvantaged (11). Furthermore, they are more likely to be uninsured or underinsured (12). These factors may lead to presentation with late disease due to decreased access to care.

Racial differences in HPV status may play a role. However, its impact remains unclear. The prevalence of tumor HPV status, an important prognostic factor in oropharyngeal cancer, has been shown to vary by race and socioeconomic status (SES).

Liederbach et al. examined the association between sociodemographic factors and HPV status in oropharyngeal squamous carcinoma, using the National Cancer Database (NCDB) (13). They found that white patients and patients residing in high SES communities had higher prevalence of HPV-positive tumors. Furthermore, HPV-positive tumors were more likely to present with nodal metastasis, but less likely to present with advanced T stage and distant metastasis. Consequently, the racial differences in stage in our study may partially reflect racial differences in HPV status. Unfortunately, the SEER database does not provide information on HPV status. Therefore, we cannot evaluate its impact as a driver for the racial disparities observed.

The present study showed that marital status was associated with risk of presenting with advanced or untreatable disease. This is consistent with findings from other studies. Inverso et al. analyzed the impact of marital status on head and neck outcomes in 51,272 patients, using the SEER database (14). They found that married patients with laryngeal and oral cancers were less likely to present with metastatic disease. Contrary to our study, they found that marital status was not associated with metastatic disease in cancers of the oropharynx, hypopharynx, and nasopharynx. This discrepancy may be due to their relatively small sample size for oropharyngeal cancer (1,357 patients). Furthermore, several studies on head and neck cancer patients have demonstrated a survival advantage for married patients (5, 6, 15, 16). The mechanism for this early presentation and survival advantage for married patients is unknown. It is possible that married patients may seek earlier medical care due to spousal pressure. In addition, married patients may have better social support and more financial resources than single patients, which can lead to improved access to care, and treatment compliance.

Our study also showed that female sex was associated with decreased risk of presenting with advanced or untreatable disease. Similarly, a study by Olsen et al., examining the impact of socioeconomic status on stage at diagnosis of head and neck cancer, also revealed decreased risk of presenting with advanced disease for female patients. The reason for this is unclear. However, gender differences in health care-seeking behavior may account for this. Several studies have shown that women are more likely than men to seek care for medical problems (17, 18).

The main strength of our study lies in its large sample size and diverse patient characteristics. Utilizing the SEER database allowed us to analyze a large and diverse population with outstanding quality control. The catchment areas used in the SEER database were selected for their ability to maintain a high-quality cancer reporting system and for demographic characteristics that are representative of the US population as a whole. We limited our analysis to patients diagnosed from 2004 to 2012 because the SEER database uses the 6th edition of the AJCC staging criteria only for cases diagnosed after 2003. Furthermore, limiting our analysis to this recent cohort provides information on the current state of health disparities. This study is primarily limited by the retrospective nature of the analysis. In addition, the SEER database does not provide information on patient-level socioeconomic factors, which may significantly impact disease presentation. As previously discussed, the lack of HPV status in the SEER database is also a limitation.

In conclusion, the present study shows that race is associated with advanced disease presentation in oropharyngeal cancer. Black patients have increased risk of presenting with Stage III or IV disease, T3 or T4 tumors, distant metastasis, and unresectable tumor. Further research is needed to identify the causes of advanced disease presentation in black patients, including the role of HPV status as a driver of racial disparities. This may reveal potential areas of opportunity for public health interventions aimed at improving access to care for this disadvantaged group.