A 77-year-old patient complains of inability to urinate, bursting pain above the pubis. The patient developed acute condition 12 hours ago. Objectively: full urinary bladder is palpable above the pubis. Rectal prostate is enlarged, dense and elastic, well-defined, with no nodes. Interlobular sulcus is distinct. Ultrasonography results: prostate volume is 120 cm3, it projects into the bladder cavity, has homogeneous parenchyma. Prostate-specific antigen rate is of 5 ng/ml. What is the most likely