Moreover, the systemic uptake of pembrolizumab into bladder mucosa after intravesical administration for ≥30 min is assured by the tumoritropic infiltration of macromolecules of comparable size such as radiolabeled dextran-99mTechnetium conjugated to epidermal growth factor (EGF) after 30 min instillation in non-muscle invasive BC patients [32]. The gene discussed is EGF; the disease is breast cancer.