Here is the design of a clinical trial:

Official Title: Androgen Deprivation Therapy for Oligo-recurrent Prostate Cancer in Addition to radioTherapy

Included conditions:
- Prostate Cancer

Study Armgroups:
- {'label': 'Radiotherapy without hormonal therapy', 'type': 'ACTIVE_COMPARATOR', 'description': 'Metastase-directed radiotherapy without the addition of hormonal therapy', 'interventionNames': ['Radiation: Radiotherapy']}
- {'label': 'Radiotherapy combined with hormonal therapy', 'type': 'EXPERIMENTAL', 'description': 'Metastase-directed radiotherapy with the addition of of short-term hormonal therapy (6 months)', 'interventionNames': ['Radiation: Radiotherapy', 'Drug: Leuprorelin']}

Interventions:
- {'type': 'RADIATION', 'name': 'Radiotherapy', 'description': 'Radiotherapy', 'armGroupLabels': ['Radiotherapy combined with hormonal therapy', 'Radiotherapy without hormonal therapy'], 'otherNames': ['MDRT', 'Metastase-directed radiotherapy', 'SBRT', 'Stereotactic body radiotherapy']}
- {'type': 'DRUG', 'name': 'Leuprorelin', 'description': 'Hormonal therapy', 'armGroupLabels': ['Radiotherapy combined with hormonal therapy'], 'otherNames': ['Eligard']}

Primary Outcomes:
- {'measure': 'Metastases progression-free survival (MPFS)', 'description': 'The primary aim of this project is to test the hypothesis that the addition of ADT to MDRT in well-selected PCa patients with oligo-metastatic disease (OM) prolongs the metastases progression-free survival (MPFS) compared to MDRT alone', 'timeFrame': '2.5 years after treatment'}

Please estimate the sample size based on the assumption: 
An alpha of 5%, power of 80%, and a dropout rate of 18% at 30 months are assumed.
Sample size
          From a previous meta-analysis, we know that the median progression-free survival in patients treated with MDRT is 21Â months [6]. This corresponds to an event rate of 50% in the MDRT group at 21Â months. For the MDRTâ+âADT group we assume a decreased event rate to 35% (65% event-free). Assuming a constant hazard of 0.0330 in the MDRT group and 0.0205 in the MDRTâ+âADT group, the metastases progression-free survival at 2.5Â years is expected to be 37.1% in the MDRT group and 54.0% in the MDRTâ+âADT group. This is associated with a hazard ratio of 0.621. Assuming an alpha of 5%, power of 80%, and a dropout of 18% at 30Â months, we need to recruit 140 patients per treatment arm and 280 patients in total.