Consequently, Cox proportional hazards models for PFS and OS (Table 2) including TNM stage (I vs. II vs. III), age (<65 years vs. ≥65 years), sex (female vs. male), histologic pattern (SCC vs. ADC vs. LCC vs. NOS), tumor grading (G1/2 vs. G3/4), stromal SMA stain (positive vs. negative) and stromal CD34 stain (negative vs. positive) were performed, respectively. Here, CD34 is linked to neoplasm.