Survival outcomes in patients with a CR, with and without a stringent dFLC response. (A) The OS was significantly better in patients with CR with additional stringent dFLC response compared with those in CR without a stringent dFLC response (P = .033: median not reached in both groups). (B) TNT in CR patients with and without a stringent dFLC response. Median TNT was not reached in the former group and was 38 months in the latter (P = .001). (C) OS was significantly better in patients with a stringent dFLC response (without CR) compared with dFLC 10 to 40 mg/L (without CR), although the median was not reached in either group (P = .043). (D) Median TNT was not reached in patients in VGPR with stringent dFLC response and was 40 months in those in a VGPR without a stringent dFLC response (P < .001).