3635 - Nasopharynx Cancer in the U.S.: Disparities in Stage at Presentation

E. C. Dee¹, R. R. Patel², K. Lapen³, Y. Wu¹, F. Yang⁴, S. Wang⁵, T. A. Patel⁶, S. McBride³, and N. Y. Lee³; ¹Memorial Sloan Kettering Cancer Center, New York, NY, ²Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, ³Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, ⁴University of Alberta, Edmonton, AB, Canada, ⁵Harvard College, Boston, MA, ⁶University of Pennsylvania, Philadelphia, PA

Purpose/Objective(s): Although nasopharynx cancer (NPC) is rare in the US, global epidemiology varies greatly. Therefore, understanding NPC disparities in the diverse US setting is critical. We explored differences in NPC stage at diagnosis in the US, with a focus on disaggregated Asian American (AA) patients. Materials/

Methods: Data from the National Cancer Database (NCDB, 2004 to 2021) identified patients with NPC; NCDB allows disaggregation by AA subgroups (Indian and Pakistani aggregated in earlier years). Patients were disaggregated by self-identified subgroup; multivariable ordinal logistic regression adjusting for demographic and socioeconomic factors defined adjusted odds ratios (aORs; higher aORs represent more advanced NPC). Models were calculated before and after disaggregation Asian American subgroups and Native Hawaiian and Other Pacific Islander groups.
Results: Of 20267 patients, most were white (12419, 61.3%), Black (3114, 15.4%), Chinese (1431, 7.1%), Filipino (549, 2.7%), and Vietnamese (441, 2.2%). Black patients and Korean patients were less likely to be insured (?2 P<0.001). Black patients and Native American patients were more likely to live in lower-income ZIP codes (?2 P<0.001); Chinese, Japanese, Filipino, Hawaiian, and Korean patients were more likely to live in higher-income ZIP codes (?2 P<0.001). Prior to disaggregation, proportion of distant metastatic disease at presentation was 43.4% among white patients (ref), 50.9% among Black patients (aOR 1.12, P=0.013), 49.5% among Native American patients (aOR 1.19, P>0.05), 41.9% among AA patients (aOR 0.97, P>0.05), and 52.0% among Native Hawaiian and other Pacific Islander patients (aOR 1.48, P=0.018). Upon disaggregation, proportion of distant metastatic disease was greatest (>50%) among Hmong (70.7%, aOR 2.91, P<0.001)), Laotian (61.9%, aOR 2.24, P=0.001), non-Hawaiian Pacific Islander (56.8%, aOR 1.83, P=0.004), and Black (50.9%, aOR 1.12, P=0.013) patients. The proportion of distant metastatic disease at presentation was similar or lower than white patients among Chinese (36.4%, aOR 0.72, P<0.001), Indian/Pakistani (38.0%, aOR 0.90, P>0.05), and Hawaiian (42.4%, aOR 1.01, P>0.05) patients. Of patients with no insurance, 61.3% presented with distant metastatic disease (vs 39.6% of those with private insurance and 42.3% of those with Medicare). Of patients in the lowest-income ZIP codes, 51.0% presented with metastatic disease, compared with 40.1% of patients in the highest-income ZIP codes (P<0.05 for these comparisons).
Conclusion: Although most NPC patients were white, Black, or Chinese, distant metastatic disease at presentation was commonest among Hmong, Laotian, non-Hawaiian Pacific Islander, and Black patients, even having adjusted for social determinants of health. These findings underscore the limitations of evaluating diverse groups as a monolith, highlighting the value of disaggregated research, and improving awareness of NPC among less canonically affected groups.