• 45-75 yo male harboring a non-treated localized prostatic adenocarcinoma of maximum Gleason score 3+4, ISUP 2 unilateral on at most maximum 2 contiguous sextants (favorable intermediate risk),with or without ipsilateral or contralateral focus of score 3+3 (ISUP1).

• Tumor visible on MRI and proven by systematic and/or targeted biopsies according to the center's practices, regardless of the route used (transrectal or transpirenal)

• Or patients under active surveillance whose follow-up prostate biopsies reveal unilateral ISUP2 on at most 2 contiguous sextants (favorable intermediate risk), with or without ipsilateral or contralateral Gleason 3+3 focus (ISUP1)

• Patients with several suspicious foci on MRI may be be included if only one of these foci is confirmed by targeted biopsies with an ISUP2 score. If more than one suspected site on MRI is confirmed by targeted biopsies, these should be unilateral ISUP2 on a maximum of 2 contiguous sextants (favourable intermediate risk), with or without an ipsilateral or contralateral site with a Gleason score of 3+3 (ISUP1).

• stage T1c-T2,

• with PSA \<20 ng/ml,

• with prostate volume less than 150 ml,

• patient clearly informed of the study and having agreed, with sufficient time for reflection to participate by signing the study's informed consent form,

• patient affiliated to or benefiting from a social security scheme