Prospective Study on the Role of Radical Prostatectomy in Oligo-metastatic Hormone-sensitive Prostate Cancer in Patients on Androgen Deprivation Therapy

Inclusion Criteria: * Written informed consent and consent for the use of personal data. * Male sex and age greater than 40 years. * Histologically or cytologically confirmed acinar adenocarcinoma of the prostate. * Oligometastatic bone disease with no more than 5 metastatic bone lesions, none located outside the spine or pelvis. \[Confirm the intended threshold because the protocol also states \<5.\] * No retroperitoneal lymph-node metastases and no visceral metastases. * No bulky pelvic lymph-node metastases greater than 3 cm. * Eligible for radical prostatectomy and lymphadenectomy. * Eastern Cooperative Oncology Group performance status 0 or 1. * Life expectancy of at least 1 year. * Receiving androgen-deprivation therapy for at least 6 months. * Serum PSA below 4 ng/mL after at least 6 months of androgen-deprivation therapy. * White blood cell count at least 3,000/mm³ and/or absolute granulocyte count at least 1,000/mm³. * Platelet count at least 100,000/mm³. * Haemoglobin at least 10 g/dL. * Serum creatinine no more than 1.5 times the upper limit of normal. * Aspartate aminotransferase less than 2.5 times the upper limit of normal. * Alanine aminotransferase less than 2.5 times the upper limit of normal. * Total bilirubin no more than 1.5 times the upper limit of normal, except in participants with documented Gilbert syndrome. * Available and willing to attend all protocol-specified follow-up visits. Exclusion Criteria: * Special histological subtypes of prostate carcinoma * PSA greater than 100 ng/mL at diagnosis before starting androgen-deprivation therapy. * Visceral metastases or retroperitoneal lymph-node metastases. * Pelvic lymph-node metastases greater than 3 cm. * More than 5 metastatic bone lesions or bone metastases outside the spine or pelvis. * Concomitant treatment with other antineoplastic agents, including investigational endocrine therapies. * Hypogonadism or severe androgen deficiency defined as serum testosterone below 100 ng/dL. * History of pituitary or adrenal insufficiency. * Concomitant or planned treatment with medicines that affect androgen metabolism, including spironolactone, ketoconazole, finasteride or dutasteride. * Active malignancy or malignancy diagnosed within the previous 5 years, except basal-cell carcinoma of the skin. * Uncontrolled arterial hypertension, defined as systolic blood pressure at least 160 mmHg or diastolic blood pressure at least 95 mmHg. Participants with a history of hypertension are eligible if blood pressure is controlled with antihypertensive treatment. * Severe uncontrolled concomitant disease or medical condition, including active uncontrolled infection. * Clinically significant cardiovascular disease, including myocardial infarction or an arterial thrombotic event within the previous 6 months, severe or unstable angina, symptomatic cardiac arrhythmia or arrhythmia requiring treatment, recent deep-vein thrombosis, pulmonary embolism, cerebrovascular event or ischaemic event. * Acute or chronic hepatitis. * Dementia or psychiatric illness that limits compliance with study requirements or may prevent understanding or signing the informed-consent form. * Previous finasteride or dutasteride treatment discontinued less than 6 months before enrolment.