Cytokine detection
The Human 27-Plex Luminex assay for cytokines was performed on serum samples of 10 patients taken pretreatment and post-treatment after 2 cycles of sintilimab. All serum samples from patients were stored at −80 °C without repetitive freezing and thawing. Cytokine levels were determined using the Luminex liquid suspension chip detection method by Wayen Biotechnologies (Shanghai, China).