The results introduce three important questions: (1) what dose(s) of mapatumumab should be evaluated in future studies of mapatumumab in NHL; (2) whether staining for TRAIL-R1 by IHC can help identify patients most likely to benefit from mapatumumab and (3) whether mapatumumab should be further evaluated as a single agent for NHL or in combination with other therapeutics that target relapsed or refractory NHL. This evidence concerns the gene TNFRSF10A and non-Hodgkin lymphoma.