Here, we report a patient with SC who showed a remarkable tumor response to PD‐1 inhibitor, pembrolizumab with carboplatin (CBDCA) plus pemetrexed (PEM), regardless of PD‐L1 tumor proportion score (TPS) 1%, and few tumor‐infiltrating lymphocytes (TILs) and few PD‐1+ immune cells were observed in tumor biopsy samples. Here, PDCD1 is linked to neoplasm.