Marieke van Son

27 RADICAL VS. FOCAL TREATMENT FOR LOCALIZED PROSTATE CANCER INTRODUCTION For localized prostate cancer, whole-gland treatments such as radiotherapy or pros- tatectomy confer excellent long-term cancer control, with 10-year biochemical dis- ease-free survival rates between 65-90% 1,2 and 10-year prostate cancer-specific sur- vival rates of nearly 100% 3-5 . However, these favourable oncological outcomes are often accompanied with detrimental side-effects, most notably urinary leakage requiring pads after prostatectomy, rectal side-effects (bleeding, loose stools, discomfort) fol- lowing radiotherapy and erectile dysfunction for both types of radical therapies 6-8 . In an effort to avoid over-treatment and its associated morbidity, many low-risk patients can be safely managed with active surveillance 9 . Tissue-preserving focal therapy (FT) has been suggested as “the middle ground” and has undergone a phased evaluation over the last 14 years. Early to medium-term outcomes from cohort studies on focal high-intensity focused ultrasound (HIFU), focal cryotherapy and focal brachytherapy have shown pad-free continence rates between 93-100% and potency preservation between 58-100% with rectal toxicity being rare 10-17 . Randomised comparative effectiveness trials comparing FT to radical therapy are underway, although delivery of such trials may be difficult 18,19 . If successful, it will take almost a decade before conclusions can be drawn 20 . Awaiting this, the best available evidence comes from cohort-based analyses. This report is a follow-up study to our previously published work 21 , comparing cancer control following radical therapy (ex- ternal beam radiotherapy [EBRT] and laparoscopic radical prostatectomy [LRP]) versus FT, using a propensity score weighted (PSW) analysis. MATERIALS AND METHODS Study design and setting EBRT data was collected from a UK single-centre retrospective registry of patients treated between January 2011-December 2018. LRP data was collected from a UK mul- ticentre prospective registry between May 2007-September 2018. FT data was collected from three prospective registries: the focal HIFU HEAT registry, focal cryotherapy ICE registry in the UK and HDR-brachytherapy in the Netherlands, including patients be- tween November 2005-February 2018. Data collection was approved by local medical research ethics committees and informed consent was obtained from all prospectively followed patients. Our study is compliant with the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) guidelines 22 . Patients Eligibility criteria were: PSA <20 ng/mL, ≤ISUP 3 and T-stage ≤T2c (National Compre- hensive Cancer Network [NCCN] low- to intermediate-risk). Patients with a history of previous prostate cancer treatment were excluded. 2