Fig. 1

Serum levels of BME cytokines and their diagnostic abilities for bone metastasis in stage IV lung cancer patients. a, b, c, d Box plots of the serum levels of the BME cytokines CaN, OPG, PTHrP, and IL-6 in three groups, including the bone metastasis group (n = 127), the non-bone metastasis group (n = 78), and the healthy control group (n = 106). From the bottom up, the boxes indicate the 25th, 50th (median), and 75th percentiles, while the bars indicate the 10th and 90th percentiles, respectively. Significance levels were obtained from the nonparametric Kolmogorov-Smirnov test: (a) P < 0.05: vs non-bone metastasis, (b) P < 0.05: vs healthy controls. e ROC analysis of the diagnostic abilities of serum bone microenvironment cytokines for bone metastasis. f ROC analysis of the diagnostic efficiencies of different combinations of the bone microenvironment cytokines for bone metastasis