In patients with breast cancer, ovarian cancer, gastric cancer, NSCLC, BLCA, READ, SARC, UCEC, MESO, KIRC, and SKCM, higher expression of BTN3A1 was associated with better prognosis; but in patients with TGCT and LGG, higher expression of BTN3A1 was associated with worse prognosis. The gene discussed is BTN3A1; the disease is breast cancer.