CD274 and neoplasm: We detected expression of PD‐L1 in the surgical specimens after neoadjuvant chemotherapy and found no staining of PD‐L1 in the tumor cells (data not shown).Complex tumor‐immune microenvironment and low PD‐L1 expression in OS may be one possible reason for unsatisfactory treatment response of PD‐1 blockade.26, 27