Randomized controlled trials have established the improved efficacy (better biochemical control and disease free survival) of combined radical radiation (70-80Gy/7-8 weeks) combined with long term hormone therapy (2-3 years of adjuvant luteinizing hormone releasing hormone (LHRH) agonist) compared to a primary hormone therapy or radiotherapy alone in men with locally advanced/high risk disease. While this approach may be tolerable in fit individuals, this combination may not be well tolerated by frail individuals or those who live at a distance who may find it difficult to attend for 7 weeks of radiation due to travel considerations. Those individuals with co-morbidities such as diabetes, coronary artery disease or osteoporosis may have those conditions exacerbated by long term hormone therapy.
This pilot study will explore the combination of a stereotactic body radiotherapy (SBRT) approach (designed to be iso-effective for late effects for standard radiotherapy) combined with one year of LHRH agonist for older men with high risk disease who are less fit (Vulnerable Elderly Score \> 3) or men unwilling to undertake conventionally fractionated therapy and three years of adjuvant hormone therapy.