This was a trial of 1113 men with T2c-T3, or pN1 prostate cancer, with 970 randomized to 6 months of ADT (starting with RT), vs 3 years ADT. RT was 50Gy WPRT with a 20Gy boost. The trial was a non-inferiority trial between the two regimens.
Median f/u was 6.4 years, and an interim analysis for futility crossed it's boundary. HR for death in the 6 month arm was 1.42 (p=0.65 for non-inferiority); 5 year OS was 84.8% in the 3 year arm vs 81.0% in the 6 month arm. DFS and BRFS were also both worse in the 6 month arm (SS). They have a number of nice QOL measures in the paper, showing decreased sexual function, increased insomnia and hot flashes in the 3 year arm, but the global QOL was similar between the arms.
There was also no difference in fatal cardiac events.
So conclusions: 6 months of ADT is "not non-inferior" to 3 years. This is a little different than saying 3 years is better than 6 months, but at the end of the day, it's hard to justify 6 months alone, in patients that would have entered on this trial.
However, that last statement is worth looking at: these T2c, T3a and T3b patients are a distinct and very small subset of high risk disease in the US in 2009. Many of the patients that we treat today are high risk because of high Gleason Grade rather than high T stage. The optimal treatment for this group is an unknown.
Comparing to the 92-02 results, which had a similar patient population, they showed a DFS and BRFS improvement, but only improved survival in the high grade sub-group. No data on subgroup analysis for this trial, but plan on seeing it in the next year or so in the JCO or similar...