A system for treating a prostate, comprising: an ultrasonic thermal therapy applicator (206, 740, 742) in the form of an elongated cylindrical applicator sized and shaped for insertion into a male patient's urethra so as to be able to reach at least partially into a prostate of said patient; a controllable motor and mechanical driver assembly coupled to said applicator (206, 740, 742) so as to cause the elongated cylindrical applicator (206, 740, 742) to rotate about an axis thereof within the patient's urethra; a plurality of transducer elements in said applicator (206, 740, 742), each being controllably driven by an electrical driving signal and having an active surface and capable of generating an acoustic radiation field emanating radially outwardly from its active surface into said prostate; a thermometry module receiving data from an imaging system and executing instructions in a processor to determine a current temperature distribution map within said prostate; characterized by the system further comprising: a temperature prediction module receiving said current temperature distribution map as data, and using programmed thermal response model instructions, generating data representative of a future temperature distribution within said prostate; and a controller (102, 700) receiving at least said future temperature distribution, comparing said future temperature distribution to an indicated reference temperature at least in some region within said prostate, and modifying the controllable electrical driving signals to said plurality of transducer elements in said applicator, so that the system is configured to carry out a real-time feed forward predictive control to an energy output of the therapy applicator (206, 740, 742). an ultrasonic thermal therapy applicator (206, 740, 742) in the form of an elongated cylindrical applicator sized and shaped for insertion into a male patient's urethra so as to be able to reach at least partially into a prostate of said patient; a controllable motor and mechanical driver assembly coupled to said applicator (206, 740, 742) so as to cause the elongated cylindrical applicator (206, 740, 742) to rotate about an axis thereof within the patient's urethra; a plurality of transducer elements in said applicator (206, 740, 742), each being controllably driven by an electrical driving signal and having an active surface and capable of generating an acoustic radiation field emanating radially outwardly from its active surface into said prostate; a thermometry module receiving data from an imaging system and executing instructions in a processor to determine a current temperature distribution map within said prostate; characterized by the system further comprising: a temperature prediction module receiving said current temperature distribution map as data, and using programmed thermal response model instructions, generating data representative of a future temperature distribution within said prostate; and a controller (102, 700) receiving at least said future temperature distribution, comparing said future temperature distribution to an indicated reference temperature at least in some region within said prostate, and modifying the controllable electrical driving signals to said plurality of transducer elements in said applicator, so that the system is configured to carry out a real-time feed forward predictive control to an energy output of the therapy applicator (206, 740, 742). a temperature prediction module receiving said current temperature distribution map as data, and using programmed thermal response model instructions, generating data representative of a future temperature distribution within said prostate; and a controller (102, 700) receiving at least said future temperature distribution, comparing said future temperature distribution to an indicated reference temperature at least in some region within said prostate, and modifying the controllable electrical driving signals to said plurality of transducer elements in said applicator, so that the system is configured to carry out a real-time feed forward predictive control to an energy output of the therapy applicator (206, 740, 742).