CD38 and neoplasm: Thus, the same configuration should be considered when similar results are seen in future investigations of PTK7-CAR T-cell’s toxicity profiles; alternatively, tuning scFv affinity and/or concomitantly integrating different co-stimulatory domains may ameliorate the potential concern of on-target off-tumor effect as typical representation for CAR T-cell therapy targeting a range of different antigens including but not limited to HER2, EGFR, CD38 (8, 51, 52).