Almost right on cue, another analysis of RTOG 0617 was published on 06/27 (sigh). Previous AI analyses have shed light on specific heart substructure and lung dosimetry as predictors of toxicity. This iteration focuses on late survival and toxicity outcomes. Less than half the rate of grade 3+ pneumonitis was seen after IMRT (8/228, 3.5%) than after 3D-conformal treatment (21/255, 8.2%). Where prior analyses did not detect clear whole heart dosimetric predictors of cardiac toxicity, simple and multivariate analyses with longer term follow-up demonstrate significantly worse overall survival when ≥20% of the heart receives 40+ Gy, a metric significantly improved among the IMRT cohort. Finally, the volume of lung receiving 5+ Gy was not clearly correlative of outcomes, supporting recent calls to dismiss this objective in favor of prioritizing favorable higher dose spill. Remember to mark 06/17 on your calendar for next year. | Chun, JAMA Oncol 2024
