Recombinant human thrombopoietin (rhTPO) is a key determinant of therapy for chemotherapy-induced thrombocytopenia (CIT) in patients with breast cancer. To assess the predictive value of preoperative inflammatory cells for response to rhTPO in breast cancer patients, a total of 198 female patients with breast cancer were enrolled between June 2011 and December 2016 in Liaoning Cancer Hospital. Peripheral blood samples before rhTPO therapy were obtained, the ratios of helper T cell (CD4+), cytotoxic T cell (CD8+), NK cell (CD16+/CD56+), and B cell (CD19+) were analyzed, and CD4/CD8 ratios were calculated. The association between each marker and response to rhTPO was analyzed using the log-rank test. Of 198 patients, response was achieved in 151 (76.26%) patients. The predictive of CD4+/CD8+ ratio gave a sensitivity and specificity of 79% and 80% in the training cohort and a sensitivity and specificity of 73% and 87% in the test cohort, when the cutoff value was set to 1.56. Plasma levels of NK cell ratio and B cell ratio were similar in either responders or nonresponders for rhTPO. Plasma CD4+/CD8+ ratio was significantly lower in responders than in nonresponders for rhTPO (1.27 ± 0.49 vs. 2.24 ± 0.92, P < 0.05). Among 83 patients with grade 2 CIT, plasma CD4+/CD8+ ratio was lower significantly in rhTPO responders than in rhTPO nonresponders (1.19 ± 0.47 vs. 2.22 ± 1.11, P < 0.05) with 83% accuracy, but we observed little significant differences in patients with grade 3/4 CIT (1.32 ± 0.51 vs. 2.25 ± 0.77, P < 0.05) with 76% accuracy. Plasma CD4+/CD8+ ratio at baseline was significantly associated with response to rhTPO. We conclude that pretreatment CD4+/CD8+ ratio is a convenient, easily measured predictive indicator for patients with breast cancer receiving rhTPO, especially in patients with grade 2 CIT.
Keywords: breast cancer; chemotherapy-induced thrombocytopenia; inflammatory cells; recombinant human TPO.