Focal Therapy for Prostate Cancer

Whole gland therapy (radical prostatectomy and radiotherapy) has been the conventional treatment for localized prostate cancer, but randomized controlled trials have not demonstrated survival benefits compared with watchful waiting or active surveillance. Whole gland therapy is also associated with significant long-term sequelae including urinary incontinence, erectile dysfunction, irradiation cystitis, and proctitis. Focal therapy has emerged as an alternative treatment modality, yet more data are needed to ensure its safety and efficacy. This is a prospective database/registry study designed to record all pre-operative, intra-operative, and post-operative parameters for patients undergoing focal therapies for prostate cancer, including but not limited to cryotherapy, high-intensity focused ultrasound (HIFU), focal laser therapy (FLA), irreversible electroporation (IRE), targeted microwave ablation (TMA). All patients who have undergone focal therapy at the Department of Surgery, Queen Mary Hospital for prostate cancer will be invited to participate, except those incapable of providing written informed consent. The primary outcome is the surgical outcomes (complications and effectiveness) of focal therapies. Secondary outcomes include identification of risk factors for treatment-related complications, provision of a readily available dataset for subsequent research, and identification of the best treatment allocation for prostate cancer patients. An estimated 200 patients will be included, with data collection from study start until 31 March 2030.

Multiparametric magnetic resonance imaging (mpMRI) is the standard imaging modality for prostate cancer diagnosis and focal therapy planning. However, 10-20% of clinically significant prostate cancers (csPCa) are not visible on mpMRI (PI-RADS 1-2). These MRI-invisible lesions, typically identified only on systematic biopsy, are currently not targetable by MRI-guided focal therapy, leaving patients with the choice between whole-gland radical treatment or active surveillance. This prospective, multi-centre, single-arm phase II trial investigates whether pelvis-only ¹⁸F-PSMA-1007 positron emission tomography-computed tomography (PET-CT) can identify MRI-invisible csPCa and serve as the therapeutic navigation tool for focal ablation. Men aged ≥50 years with localized, intermediate-risk prostate cancer (ISUP Grade Group 2-3) and at least one MRI-invisible csPCa focus undergo a PET-CT. If a PET-avid lesion corresponds anatomically to the MRI-invisible biopsy-positive site, the patient receives focal therapy using an energy modality (targeted microwave ablation, high-intensity focused ultrasound, or irreversible electroporation) selected based on tumour anatomy, guided by organ-based tracking. The primary endpoint is the absence of csPCa (Grade Group ≥2) on 6-month targeted biopsy of all treated zones. Secondary endpoints include out-of-field recurrence, functional outcomes, and safety. The study requires 45 treated patients (total enrolment \~60) across two Hong Kong centres and will be completed within 3 years.