No abstract

Background The establishment of biomarkers that can be used to predict the response to immunotherapy for malignancy is extremely important. In particular, noninvasive analysis of immune cells from peripheral blood before treatment has gained increased attention, and natural killer (NK) cell activity has been shown to be related to treatment response. Here, we aimed to confirm the relationship between the response to immunotherapy and NK cell activity. Methods In this prospective observational study, patients with advanced NSCLC who were scheduled for immunotherapy from October 2018 to December 2019 were enrolled. Baseline NK cell activity was compared according to the best clinical response to immunotherapy. Results A total of 54 patients with advanced NSCLC were enrolled, and 34 patients were analyzed. The baseline NK cell activity was significantly higher in the non‐PD group than in the PD group ( P = 0.002). At the cutoff level of ≥1200 pg/mL, baseline NK cell activity yielded a sensitivity of 80% and a specificity of 68.4% in predicting the response to immunotherapy (AUC = 0.8, P < 0.003). The median progression‐free survival (PFS) was significantly better in the high NK group ( P = 0.003), and correlation between baseline NK cell activity and PFS was also confirmed (r = 0.517, P = 0.002). Conclusions Baseline NK cell activity was related to the response to immunotherapy and the PFS. We suggest that NK cell activity from peripheral blood before immunotherapy is a noninvasive, simple, and novel way to predicting the treatment response in patients with NSCLC. Key points Significant findings of the study The response to immunotherapy was significantly better in patients with high baseline NK cell activity, and there was a significant correlation between baseline NK cell activity and PFS. What this study adds This study demonstrates the efficacy of baseline NK cell activity from peripheral blood as a biomarker for predicting immunotherapy response.

Background: Although liver metastasis occurs in approximately 15% of metastatic non-small cell lung cancer (NSCLC) patients with poor prognosis, its prognostic effect in patients who receive immunotherapy is unclear. This study aimed to verify the effects of liver metastasis on the prognosis of metastatic NSCLC patients according to their first-line treatment.Methods: Patients who were initially diagnosed with stage 4 NSCLC from January 2015 to December 2019 were analyzed in this retrospective real-world data-based study. The patients were divided into three groups according to the type of first-line chemotherapy they received: cytotoxic, targeted, and immunotherapy.Prognosis was then compared depending on the presence of liver metastasis in each treatment group.Results: Among the 1,470 patients, 723 (49.2%) received cytotoxic chemotherapy, 678 (46.1%) received targeted therapy, and 69 (4.7%) received immunotherapy as their first-line chemotherapy. A total of 234 (15.9%) patients had liver metastasis at the initial diagnosis. The mean patient age was 63.7 years, and 59.1% were male. There was no difference in overall survival (OS) in the immunotherapy group in patients with or without liver metastasis (11.7 vs. 13.0 months, P=0.968); however, patients with liver metastasis had worse outcomes in the cytotoxic and targeted therapy groups compared to patients without liver metastasis. Furthermore, in patients with liver metastasis, the immunotherapy group had a longer OS than the cytotoxic chemotherapy group (11.7 vs. 4.4 months, P<0.001). Liver metastasis was associated with poor outcomes (hazard ratio of 1.438), as were age, male sex, bone, adrenal gland, or soft tissue metastasis, and three or more metastatic sites; however, lymph node, brain, collateral lung, and pleura metastasis did not affect prognosis.Conclusions: Although liver metastasis was associated with poor outcomes, it did not affect prognosis in patients who received immunotherapy.