ASCO 2018: Long-Term Androgen Deprivation, With or Without Radiotherapy, in Locally-Advanced Prostate Cancer: Updated Results from a Phase III Randomized Trial

Chicago, IL (UroToday.com) There is a need to know whether there is a beneficial effect for the addition of external beam radiation therapy (EBRT) to long term androgen deprivation therapy (ADT), in patients with locally advanced prostate cancer. The authors of this study presented long term results (7.3 year median follow-up) of this specific trial published in 2012.[1]

This was phase 3 trial recruiting patients from 2000 to 2003 with non-metastatic biopsy proven locally advanced prostate cancer (stage T3-T4). The primary endpoint was progression free survival (PFS). Additional endpoints included overall survival (OS) locoregional progression free survival (LPFS), metastasis free survival (MFS), biochemical progression free survival (BPFS) and tolerance. Patients were recruited and randomized (1:1) to ADT alone or ADT combine with EBRT. ADT was given in the form of 3 monthly injections of leuprorelin 11.25 mg for a duration of 3 years.

Overall 262 patients were included in the analysis. The 8-year PFS was significantly higher in the ADT-EBRT arm compared to EBRT alone (47.9% vs. 7%, HR 0.27, p<0.0001, figure 1).

image 44Figure 1 – Kaplan Meyer graphs of Progression free survival (A) and overall survival (B)

The 8-year OS rate was 56.8% in the ADT alone arm and 65.1% in the combination arm (p=0.43, figure 1). LPFS was significantly in favor of the ADT and EBRT arm (HR 0.61, p=0.01). No difference was demonstrated in the MFS.

The authors concluded that this study shows that the addition of EBRT to prolonged ADT significantly improves oncological outcomes for locally advanced prostate cancer, and represents level 1 evidence for this population.


Presented by: Barry W. Goy, Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre, Twitter:@GoldbergHanan at the 2018 ASCO Annual Meeting - June 1-5, 2018 – Chicago, IL USA

References:
[1] Motet N. et al. Addition of radiotherapy to long-term androgen deprivation in locally advanced prostate cancer: an open randomised phase 3 trial. Eur Urol. 2012 Aug;62(2):213-9. doi: 10.1016/j.eururo.2012.03.053. Epub 2012 Apr 3.