Further, 21.2 ± 2.8 days after anti-PD-L1 treatment cessation PDX volume duplication was registered in the primary luminal bladder cancer subgroup vs. 9.4 ± 0.3 days in the control subgroup (p = 0.001); 17.3 ± 1.7 days after completion of experimental treatment, we registered tumor volume doubling in the primary basal NMIBC subgroup vs. 10.8 ± 1.6 in control mice (p = 0.01). The gene discussed is CD274; the disease is urinary bladder carcinoma.