The Headline: PAM50 has previously been shown to be a predictive biomarker of androgen deprivation therapy benefit in patients receiving radiation for prostate cancer.
The Study: Among the PAM50 molecular subtypes, prior studies have identified Luminal B as the one that benefits most from ADT. In this study, PAM50 was used to analyze samples from patients treated on RTOG 0534 (SPPORT). Recall that in SPPORT, patients receiving salvage RT for detectable PSA after prostatectomy were randomized to receive fossa only RT, fossa plus short course ADT, or fossa plus ADT plus pelvic nodal RT. Luminal B subtype was significantly associated with freedom from progression and metastasis free survival. Those with Luminal B disease had significantly greater improvement in FFP at 5 years with the addition of ADT (31% absolute improvement v 10%). Absolute improvement in 10 year metastasis free survival from the addition of ADT was also significantly greater in the Luminal B subgroup (20% v -3%).
TBL: In the SPPORT trial, patients with Luminal B molecular subtype had a greater benefit from the addition of ADT than those of other molecular subtypes. | Tran, ASTRO 2026
The Study: Among the PAM50 molecular subtypes, prior studies have identified Luminal B as the one that benefits most from ADT. In this study, PAM50 was used to analyze samples from patients treated on RTOG 0534 (SPPORT). Recall that in SPPORT, patients receiving salvage RT for detectable PSA after prostatectomy were randomized to receive fossa only RT, fossa plus short course ADT, or fossa plus ADT plus pelvic nodal RT. Luminal B subtype was significantly associated with freedom from progression and metastasis free survival. Those with Luminal B disease had significantly greater improvement in FFP at 5 years with the addition of ADT (31% absolute improvement v 10%). Absolute improvement in 10 year metastasis free survival from the addition of ADT was also significantly greater in the Luminal B subgroup (20% v -3%).
TBL: In the SPPORT trial, patients with Luminal B molecular subtype had a greater benefit from the addition of ADT than those of other molecular subtypes. | Tran, ASTRO 2026