Patient characteristics
There were 86 (14.3%) female and 517 (85.7%) male patients with newly diagnosed ESCC. There were 279 (46.3%) young patients whose age at first diagnosis≤60 years and 324 (53.7%) old patients (>60 years). 105 (17.4%) patients had pathological stage 1a-1b, 205 (34.0%) patients had pathological stage 2a-2b, and 293 (48.6%) patients had pathological stage 3a-3c.There were 180 (29.9%) patients who had vessel invasive, and 423 (70.1%) patients without vessel invasive. There were 215(35.7%) patients who had nerve infiltration, and 388 (64.3%) without nerve infiltration. 408 (67.7%) patients with surgery only, 137 (22.7%) patients who received postoperative chemotherapy, and 58 (9.6%) patients who received radiotherapy and chemotherapy after operation. The median value of the preoperative neutrophil count was 3.5, and the quartile interval is 2.8-4.5. The median value of the postoperative neutrophil count was 6.2, and the quartile interval is 5.0-7.6. Details of clinical features were shown in Table 1. Significant differences in the neutrophil count was observed prior to and following surgery (P<0.001) (Figure 1).
Relationship between neutrophil change and clinical features
The clinical data of patients in neutrophil change(Nc) <2.60 group and in neutrophil change(Nc) ≥2.60 group are listed in Table 1. There were no significant difference between the two groups in terms of clinical data including sex, age, depth of tumor, lymph node metastasis, pathological stage, pathology grade, vessel invasive, nerve infiltration, and treatment regimen. The median of Pre-Neutrophil and Post-Neutrophil were both higher in neutrophil change(Nc) ≥2.60 group than in neutrophil change(Nc) <2.60 group (both P <0.001).
Prognostic variables for OS
In univariate analysis, six parameters including neutrophil change(Nc)(≥2.60 vs.<2.60) (P=0.010), depth of tumor (P<0.05), lymph node metastasis (P<0.05), pathological stage (P<0.001), vessel invasive (absence vs. presence) (P<0.001), and nerve infiltration (absence vs. presence) (P<0.001) predict worse OS. Multivariate analysis revealed that neutrophil change(Nc)(≥2.60 vs.<2.60) (P=0.022), lymph node metastasis (P<0.05), and nerve infiltration (absence vs. presence) (P=0.005) could serve as independent prognostic markers of worse OS (Table 2). OS of patients with neutrophil change(Nc)(<2.60) group were notably worse compared to patients with neutrophil change(Nc)(≥2.60) group (P=0.016) (Figure 2).
Subgroup analysis according to other clinical features
To investigate the subgroups of patients with ESCC impacted by neutrophil change(Nc), we classified patients based on gender (male, n=517; female, n=86), age (≤60, n=279; >60, n=324), pathological stage (1a-1b, n=105; 2a-2b, n=205; 3a-3c, n=293), vessel invasive (Yes, n=180; No, n=423), and nerve infiltration(Yes, n=215; No, n=388). OS of male patients, age≤60 patients, patients without vessel invasive and patients without nerve infiltration were dramatically worse for those with neutrophil change(Nc)(<2.60) (P=0.013, P=0.002, P=0.004, and P=0.014), but OS did not differ in female patients, age>60 patients, patients with vessel invasive and patients with nerve infiltration (Figure 3- Figure 7). Patients with pathological stage 3a-3c tend to have worse OS in neutrophil change(Nc)(<2.60) group than in neutrophil change(Nc)(≥2.60), but do not reach statistical difference (P=0.050).