Older women with triple-negative breast cancer received less adjuvant therapyOlder group: higher androgen receptor, lower CK5/6, tumor-infiltrating lymphocytesAndrogen receptor positivity benefits older patientsTumor-infiltrating lymphocyte status not influential in outcomesPatients with androgen receptor–positive triple-negative breast cancer may avoid systemic therapyNo age-based differences in histology. This evidence concerns the gene KRT5 and neoplasm.