S100B and small cell lung carcinoma: Mu et al. further examined serum S100B in SCLC patients and found elevated levels in BM+ compared to BM− (P = .001).37 However, in Kondrup et al., despite elevated S100B levels in LCBM+ patients, there was no statistical evidence of a difference (P = .852),19 indicating a weaker performance of S100B as a diagnostic marker in this cohort.