CD274 and neoplasm: In summary, age ≥ 50–60 years, tumor size ≥ 3 cm, poor pathological differentiation, Ki-67 labeling index ≥10%, SUVmax > 6.5, HER-2/neu immunostaining and amplification, PD-L1-positive, lymph node metastases, and distant metastases are associated with poor prognostic factors in PMEC.