Previously, our group showed promising in vivo results of the in-house developed [89Zr]Zr-DFO-B11-anti-PD-L1 (herein, [89Zr]Zr-B11-IgG) compound featuring a full-length humanized IgG antibody which was able to distinguish between PD-L1 expressing and PD-L1 knockout tumors in breast cancer and an melanoma animal model [21]. The gene discussed is CD274; the disease is breast carcinoma.