BackgroundEvidence-practice gaps exist in urology. We previously surveyed European Association of Urology (EAU) guidelines for strong recommendations underpinned by high-certainty evidence that impact patient experience for which practice variations were suspected. The recommendation “Do not offer neoadjuvant androgen deprivation therapy (ADT) before surgery for patients with prostate cancer” was prioritised for further investigation. ADT before surgery is neither clinically effective nor cost effective and has serious side effects. The first step in improving implementation problems is to understand their extent. A clear picture of practice regarding ADT before surgery across Europe is not available. ObjectiveTo assess current ADT use before prostate cancer surgery in Europe. Design, setting, and participantsThis was an observational cross-sectional study. We retrospectively audited recent ADT practices in a multicentre international setting. We used nonprobability purposive sampling, aiming for breadth in terms of low- versus high-volume, academic, versus community and public versus private centres. Outcome measurements and statistical analysisOur primary outcome was adherence to the ADT recommendation. Descriptive statistics and a multilevel model were used to investigate differences between countries across different factors (volume, centre type, and funding type). Subgroup analyses were performed for patients with low, intermediate, and high risk, and for those with locally advanced prostate cancer. We also collected reasons for nonadherence. Results and limitationsWe included 6598 patients with prostate cancer from 187 hospitals in 31 countries from January 1, 2017 to May 1, 2020. Overall, nonadherence was 2%, (range 0–32%). Most of the variability was found in the high-risk subgroup, for which nonadherence was 4% (range 0–43%). Reasons for nonadherence included attempts to improve oncological outcomes or preoperative tumour parameters; attempts to control the cancer because of long waiting lists; and patient preference (changing one’s mind from radiotherapy to surgery after neoadjuvant ADT had commenced or feeling that the side effects were intolerable). Although we purposively sampled for variety within countries (public/private, academic/community, high/low-volume), a selection bias toward centres with awareness of guidelines is possible, so adherence rates may be overestimated. ConclusionsEAU guidelines recommend against ADT use before prostate cancer surgery, yet some guideline-discordant ADT use remains at the cost of patient experience and an additional payer and provider burden. Strategies towards discontinuation of inappropriate preoperative ADT use should be pursued. Patient summaryAndrogen deprivation therapy (ADT) is sometimes used in men with prostate cancer who will not benefit from it. ADT causes side effects such as weight gain and emotional changes and increases the risk of cardiovascular disease, diabetes, and osteoporosis. Guidelines strongly recommend that men opting for surgery should not receive ADT, but it is unclear how well the guidance is followed. We asked urologists across Europe how patients in their institutions were treated over the past few years. Most do not use ADT before surgery, but this still happens in some places. More research is needed to help doctors to stop using ADT in patients who will not benefit from it.