Objective To investigate blood index changes after chemotherapy of patients in lung cancer, in order to find relevant index to predict tolerance of chemotherapy.

Methods A retrospective analysis of 311 cases of lung cancer patients. Input case data and blood routine index, set up the database, and analyse the data by single factor and multi-factor variable Spearman correlation.

Results In all patients, Anemia analysis showed that the total number of cycles of anemia after chemotherapy account for 1 269(83.60%), without anemia was 249 cycles (16.40%), including the total number of cycles of mild anemia after chemotherapy account for mild anemia 1 100 (86.68%), moderate anemia cycles 155 (12.21%), severe anemia cycles 12 (0.95%), and extremely severe anemia cycles was 2 (0.16%). and there are statistically significant in which positive expression of red blood cell count, hemoglobin, hematocrit, and mean corpuscular volume is different between different degrees of anemia. Single factor analysis showed that pathological type, tumor stage, gender, and chemotherapy cycle were closely related to the positive expression of peripheralblood associated granulocyte and erythroid (P < 0.05), which was statistically significant. Spearman correlation analysis showed that there was a correlation between the percentage of neutrophils, red blood cell count, hemoglobin and hematocrit, and there was a correlation between chemotherapy tolerance and red blood cell count, hemoglobin, hematocrit. Hematocrit is a independent factor for prediction of chemotherapy tolerance.

Conclusion Hematocrit has a certain value in predicting lung cancer patients' chemotherapy tolerance.