Health Services Research
PV QA 3 - Poster Viewing Q&A 3
TU_38_2973 - Trends in incidence rates for HPV-related and HPV-unrelated squamous cell carcinomas of the head and neck in New Mexico American Indians, Hispanics, and non-Hispanic whites, 1995-2014
Tuesday, October 23
1:00 PM - 2:30 PM
Location: Innovation Hub, Exhibit Hall 3
Trends in incidence rates for HPV-related and HPV-unrelated squamous cell carcinomas of the head and neck in New Mexico American Indians, Hispanics, and non-Hispanic whites, 1995-2014
G. N. Gan1, Z. Galochkina2, A. Cowan3, E. Yilmaz4, T. M. Schroeder5, B. Liem6, D. Y. Lee5, J. H. Lee7, and C. Wiggins7; 1Department of Internal Medicine, Section of Radiation Oncology, University of New Mexico School of Medicine, Albuquerque, NM, 2UNM CCC, Albuquerque, NM, 3Department of Surgery, University of New Mexico, Albuquerque, NM, 4University of New Mexico Comprehensive Cancer Center, Albuquerque, NM, 5University of New Mexico, Albuquerque, NM, 6UNM Comprehensive Cancer Center, Albquerque, NM, 7UNM Comprehensive Cancer Center, Albuquerque, NM
Purpose/Objective(s): The incidence rates for HPV-related head and neck squamous cell carcinoma (HNSCC) have increased in the last three decades. New Mexico (NM) is home to a unique population of Hispanics (H) and one of the largest number of American Indians (AI). Historically both groups had lower rates of tobacco-related cancers than non-Hispanic whites (NHW) in NM, while prevalence of HPV infection was thought to be similar among these 3 groups. We hypothesized that HNSCC incidence rates varied by race/ethnicity in New Mexico during the study period, but that trends in incidence rates were similar to those observed in other populations.
Materials/Methods: New Mexicans diagnosed with HNSCC during the time period 1995-2014 were identified from existing records of the population-based NM Tumor Registry. Cases were defined as HPV-related or -unrelated based on previously defined anatomic sub-sites. Average-annual, age-adjusted incidence rates and corresponding 95% confidence intervals (CI) were calculated by the direct method with SEER*Stat software, using the US 2000 standard population for age-adjustment. Rates were calculated by race/ethnic group (AI, H, and NHW) during the entire study period and by four, 5-year time periods (1995-99, 2000-04, 2005-09, and 2010-14). Annual percent change (APC) in incidence rates across the study period was assessed with simple linear regression.
Results: Average annual, age-adjusted incidence rates for HNSCC were highest for NHW (10.7 per 100,000 person-years; 95% CI 10.3-11.1), followed by H (7.3, 95% CI 6.9-7.8) and AI (3.7, 95% CI 3.0-4.6). Rates for HPV-related cancers also varied by race/ethnicity: 3.1 for NHW, 95% CI 2.9-3.3; 1.7 for H, 95% CI 1.5-1.9; and 0.5 for AI, 95% CI 0.3-0.9. Similar patterns were observed for HPV-unrelated cancers: 7.6 for NHW, 95% CI 7.3-8.0; 5.7 for H, 95% CI 5.2-6.1; and 3.2 for AI, 95% CI 2.5-4.0. Rates for HPV-related cancers increased during the study period for all race/ethnic groups: NHW, 4.3 APC (p=0.; H, 3.5 APC (p=0.085); and AI, 7.4 APC (p=0.178). In contrast, rates for HPV-unrelated sites decreased for NHW (-1.4 APC, p=0.129), H (-1.9 APC, p=0.211), and AI (-0.9, p=0.656). Patients with HPV-related HNSCC had significantly better cause-specific and overall survival than HPV-unrelated HNSCC. AI had poorer survival than Hispanics and NHW for HPV-related and -unrelated cancers. Survival differences between groups was not statistical significance.
Conclusion: Incidence rates for HNSCC varied by race/ethnicity in NM. Rates for HPV-related cancers increased in all 3 race/ethnic groups, but was only statistically significant for NHW. In contrast, rates for HPV-unrelated cancer decreased for NHW and Hispanics, but remained relatively constant among AI. The relatively small number of cases in this sparsely populated state constrains interpretation of these results.
Author Disclosure: G.N. Gan: None. Z. Galochkina: None. E. Yilmaz: None. T.M. Schroeder: None. B. Liem: None. J. Lee: None. C. Wiggins: None.