Background: Stage IV lung cancer is the most advanced lung cancer state accompanied by metastasized to the area around the lungs or distant major organs. The most common type of lung cancer is non-small cell lung cancer, which is more aggressive and may spread quickly due to organ-specific complex networks such as lymph and major blood vessels. Thus, only precise diagnostic strategy approaches will determine the effectiveness of the actual and successful clinical treatment. Until a recent date, Immunohistochemistry (IHC) for programmed death-ligand 1(PD-L1) test is the only available biomarker test that purpose diagnostics (CDx) and guide the treatment with immune checkpoint inhibitors in NSCLC. Methods: Given that CDx strategy, tissue biopsy has inevitable limitations, including patient risk, repetitive examination, sample preparation, sensitivity, and accuracy. For this reason, our research team contrived the best strategy for biomarker, PD-L1-specific CTCs in stage IV NSCLC group (N = 30) compared to pulmonary inflammatory patient groups (N = 30) CytoGen Smart biopsy platform. Herein, we removed false-positive cells for the first strategy of distinguishing between lymphoid/myeloid cells and the enriched-CTCs. And the second strategic approach is to calculate the pure CTCs (without false-positive cells) and then CTPS) as measured by the PD-L1 expression among pure-CTCs. That application is the percentage of viable CTCs showing partial or complete stained cells at the deducted cut-off value in each fluorescence, respectively. Results: Consequently, we demonstrated over 80% of the concordance rate between VENTANA PD-L1(SP263) and DAKO PD-L1(SP263) assay tested by the PD-L1 expression on stage IV NSCLC in tissue and pure-CTCs based CTPS from the blood. In contrast, pure-CTCs based CTPS in the pulmonary inflammatory group were all negative (recorded as zero). Conclusions: Conclusively, this study implicates that pure-CTCs based CTPS could be deployed for innovative diagnosis strategies as alternatives for tissue biopsy. Our clinical study's data suggested that the possibility for prompt decision for diagnosis and gain powerful insights to guide the personalized treatment in NSCLCs. Clinical trial information: 2020-0553.