To explore the value of SPECT/CT imaging on programmed death receptor 1 ligand (PD-L1) expression in patients with non-small cell lung cancer (NSCLC) based on ⁹⁹Tc^m labeled anti-PD-L1 nanoantibodies (NM-01).

From January 2019 to March 2020, a total of 14 patients (11 males, 3 females; age: (61.9±11.0) years) with pathologically confirmed NSCLC in Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine were prospectively enrolled. NM-01 were labeled with ⁹⁹Tc^m, and patients were recruited for SPECT/CT imaging 2 h after injection with ⁹⁹Tc^m-NM-01((359.1±68.0) MBq). The differences of SUV_max in primary and metastatic lesions between PD-L1 positive and negative patients were compared by independent sample t test. The correlation between the SUV_max and PD-L1 expression of primary lesions was analyzed by Pearson correlation analysis.

Of 14 patients, 6 were PD-L1 positive and 8 were PD-L1 negative. ⁹⁹Tc^m-NM-01 showed obviously increased uptake in kidneys and liver, while mildly increased uptake in spleen and bone marrow. The SUV_max of primary lesions was 4.69±1.88 and the SUV_max of metastatic lesions was 2.04±1.32. The SUV_max of primary lesions in PD-L1 positive patients was significantly higher than that of PD-L1 negative patients (5.99±1.99 vs 3.72±1.10; t=5.98, P=0.039). There was no significant difference in the SUV_max of metastatic lesions between PD-L1 positive and negative patients (1.66±1.03 vs 2.35±1.46; t=-1.77, P=0.084). The SUV_max of primary lesions was positively correlated with PD-L1 expression (r=0.648, P=0.042).

⁹⁹Tc^m-NM-01 can demonstrate the expression of PD-L1 in primary and metastatic lesions in NSCLC.

Carcinoma, non-small-cell lung; Antibodies; Nanotechnology; Programmed cell death 1 receptor; Technetium; Gallium radioisotopes; Positron-emission tomography; Tomography, emission-computed, single-photon