OBJECTIVES: Genetic mutations in ERBB2, TP53, PIK3CA, BRAF, EGFR and KRAS are linked to a higher susceptibility for developing breast cancer. Thus, genetic evaluation is a critical part of patient care. This study evaluated differences in U.S. age demographics and genotype testing in a real-world population of patients with advanced breast cancer (ABC) between 2014 and 2022.

METHODS: Using curated, structured, de-identified electronic health records data from 17 U.S. centers in the TriNetX Research Network, a cohort of 20,339 ABC patients who received genetic testing were identified. Data enriched with lab, genomic, pathology, NLP-abstracted, and death registry data were analyzed to assess demographic and clinical characteristics summarized using descriptive statistics. The population was matched and stratified by age category (<65 and >=65) and genetic test. Groups were compared using a Cochran–Mantel–Haenszel test. Statistical tests were conducted at the alpha=0.05 level of significance.

RESULTS: Of the ABC patients identified, the mean (SD) age of women in the study was 68.5 (12.8) years. Among these women 8,556 (42%) were Black, 7,765 (38%) were White, 505 (2%) were Asian, and 19 (1%) were other. Women over the age of 65 underwent significantly more testing than women under 65 years (p<0.001). The following shows the number of each test performed by age category (65+ vs <65) ERBB2 = 11,515 vs. 8,053, TP53 = 117 vs. 96, KRAS = 150 vs. 31, PIK3CA =105 vs. 61, BRAF = 80 vs. 32, EGFR expression = 64 vs. 35.

CONCLUSIONS:

These findings demonstrate that there are statistically significant differences in genetic testing utilization favoring patients 65 and older in a population of real-world advanced breast cancer patients.