Survival disparities in non-small cell lung cancer: Disaggregating Asians from NHPI and identifying variability among common Asian subgroups - The largest single-center study in Hawai'i

Abstract

Background: The American Cancer Society and the National Cancer Institute emphasize the need to disaggregate data for U.S. Asian, Native Hawaiian, and Other Pacific Islander (NHPI) populations to better understand racial disparities in cancer outcomes. Asian populations are diverse, with distinct genetic, cultural, and socioeconomic backgrounds that differ from those of NHPI, influencing cancer prognosis. This study analyzes non-small cell lung cancer outcomes among Asian and NHPI populations.

Methods: This retrospective cohort study identified NSCLC patients treated at Queen's Medical Center in Honolulu, Hawai'i, from 2000 to 2022. Patients were categorized into six racial/ethnic groups: White, Chinese, Japanese, Filipino, Other Asians, and NHPI. Survival differences were evaluated using Kaplan-Meier analysis and Cox proportional hazards models.

Results: The cohort comprised 4160 patients, including 977 White, 419 Chinese, 968 Japanese, 724 Filipino, 217 Other Asians, and 855 NHPI patients. NHPI had the highest proportion of individuals under 60 years old (27.5 %), the highest percentage of Medicaid/uninsured (37 %), and the lowest proportion receiving surgery (23.4 %) compared to other races (p < 0.001). Median overall survival (OS) was 20.9 (18.3-23.5) months for White patients, 22.3 (17.8-26.9) months for Chinese patients, 17.7(15.3-20.2) months for Japanese patients, 19.7(16.1-23.3) months for Filipino patients, 25.7(14.7-36.6) months for Other Asians patients and 14.7(12.0-17.3) months for NHPI patients (p < 0.001). Asian NSCLC patients had a lower risk of death compared to White patients (adjusted HR 0.89, 95 % CI 0.85-0.97, p = 0.010). In contrast, NHPI patients had a higher mortality rate compared to White patients (adjusted HR 1.15, 95 % CI 1.03-1.28, p = 0.011) in the multivariable analysis without treatment. However, both associations were no longer statistically significant after additional adjustment for treatment. Subgroup analyses of Asian patients compared to Whites patients revealed that the Chinese patients had the lowest risk of death, with this difference remaining significant even after adjusting for treatment (adjusted HR 0.82, 95 % CI 0.72-0.93, p = 0.003).

Conclusion: Our findings demonstrate the heterogeneity in NSCLC outcomes between U.S. Asians and NHPI patients as well as among individual Asian ethnic populations. Further research is needed to validate these differences and their clinical implications.

Keywords: Asian; Native Hawaiian and Pacific Islander; Non-small cell lung cancer; Racial disparities; Survival outcome.