The FLAME trial showed that focal boost to MRI-defined intraprostatic disease improved DFS in patients with intermediate and high risk prostate cancer. Do all patients benefit the same, though? This study looked at 120 FLAME patients who received a D98% >85 Gy to the boost volume to determine if certain subgroups gained more benefit from focal boost compared to patients who received a standard whole gland dose. While patients with increasing numbers of high risk factors (GG 4-5, T3, PSA>20) had worse DFS in the standard dose arm, focal boost appeared to negate the effects of high risk factors with similar DFS across risk groups. Likewise, the difference in DFS between standard dose and focal boost widened as the grade group increased from 1 to 2-3 to 4-5. Those with GG 1 disease did well with or without boost while those with GG 4-5 disease did poorly without the boost. | Guricova, Int J Radiat Oncol Biol Phys 2023
