Transrectal ultrasound probe for boiling histotripsy ablation of prostate are presented herein. In one embodiment, a method for a transrectal ultrasound treatment uses high intensity focused ultrasound (HIFU). The method includes: generating a boiling histotripsy (BH) therapy ultrasound by a therapy transducer in a frequency range of 1 MHz to 2.8 MHz and a surface intensity range of 10 W/cm2 to 80 W/cm2. The therapy transducer may be about 50 mm long and about 35 mm wide. The method also includes applying the therapy ultrasound by directing ultrasound pulses having ultrasound shock waves to a target tissue at a focal depth of 2.5 cm to 5.5 cm; generating at least one μm-scale vapor bubble at a target region; growing the at least one vapor bubble to at least one mm-scale bubble; and mechanically disintegrating a surrounding tissue by interactions between mm-scale bubbles and the ultrasound shock waves within a pulse.