SBRT and Hormone Therapy for Oligometastatic Prostate Cancer.

Objectives & purpose

We report preliminary results of SBRT-SG05 (NCT02192788) phase II trial testing SBRT and hormone therapy (HT) in the oligorrecurrence setting on prostate cancer oligometastic patients. The primary endpoint of this study is to determine local and symptomatic oligometastases control. Key secondary endpoints are biochemical control, progression free survival, chemotherapy free survival, overall survival and impact of treatment on quality of life.

Materials & methods

Patients with histologically confirmed prostate cancer (hormone-sensitive or castration-resistant) patients in an oligorrecurrent stage after primary treatment were assigned to receive SBRT for their metastases and HT. The Inclusion Criteria were: Time to biochemical recurrence >1 year; PSA-DT > 2 months; Less than 5 bone or lymph node metastases by Choline PET-CT or / and WB-DWI-MRI. All patients should have HT according to current recommendations planning its withdrawal within two years after treatment if biochemical control has been achieved.

Results

From December 2015 to February 2017, 54 patients recruited at 12 centers. At the time of the analysis 59 lesions had been treated and evaluated.  Median follow-up of the cohort is 6 months (range 1-24 moths).  To date, 4 patients (8.7%) have presented disease progression. Moderate-severe toxicities (grades 2-4) have not been observed.

Conclusion

This trial presents a favorable pace of recruitment with good initial figures of local control without the appearance of remarkable toxicity at this time.