Associations of immune checkpoint inhibitor therapy efficacy with clinical parameters and tumor­infiltrating CD68­positive cell counts in patients with EGFR­mutant non­small cell lung cancer.

Immune checkpoint inhibitor (ICI) therapy has been less effective in patients with non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations than in patients with EGFR wild-type NSCLC. This retrospective study was conducted to investigate the associations of clinical parameters with the efficacy of ICI therapy in patients with EGFR-mutant NSCLC. Clinical information was retrieved from the medical charts, and immunohistochemical analysis was performed in some cases to determine the tumor-infiltrating CD68-positive cell count. Data from 46 patients were included in the analysis. The median (95% confidence interval) progression-free survival and overall survival from the initiation of ICI therapy was 1.4 months (1.0-1.7 months) and 6.4 months (3.9-19.0 months), respectively. Analysis using a Cox proportional hazards model revealed that tumor programmed death-ligand 1 expression was associated with the overall survival of patients with EGFR-mutant NSCLC after ICI treatment. The tumor-infiltrating CD68-positive cell count was evaluated in 11 patients. Comparison using the log-rank test revealed that the progression-free survival time after ICI treatment was longer in the patients with lower tumor-infiltrating CD68-positive cell counts than those with higher tumor-infiltrating CD68-positive cell counts. The present analysis demonstrated that PD-L1 expression and the tumor-infiltrating CD68-positive cell count may be associated with the efficacy of ICI therapy in patients with NSCLC harboring EGFR mutations.

Efficacy of immune checkpoint inhibitor therapy in patients with pulmonary sarcomatoid carcinoma in clinical practice.

OBJECTIVE: Studies have suggested the potential efficacy of immune checkpoint inhibitors (ICIs) for pulmonary sarcomatoid carcinoma. This multicenter observational study was conducted to evaluate the efficacy of systemic ICI therapy and chemoradiation followed by durvalumab therapy for pulmonary sarcomatoid carcinoma. METHODS: We analyzed the data of patients with pulmonary sarcomatoid carcinoma who received systemic ICI therapy or chemoradiation followed by durvalumab therapy between 2016 and 2022. RESULTS: In this study, data of a total of 22 patients who received systemic ICI therapy and four patients who received chemoradiation followed by durvalumab therapy were analyzed. In the patients who received systemic ICI therapy, the median progression-free survival after initiation of therapy was 9.6 months, and the overall survival did not reach the median. The 1-year progression-free survival rate and overall survival rate were estimated to be 45.5% and 50.1%, respectively. Although the log-rank test revealed no significant association between the tumor expression level of programmed death ligand-1 (tumor proportion score evaluated using 22C3 antibody: ≥50% vs. <50%) and the survival duration, the majority of patients showing long-term survival showed a tumor proportion score of ≥50%. Of four patients treated with chemoradiation followed by durvalumab therapy, two patients showed an overall survival of ≥30 months, whereas the remaining two patients died within 12 months. CONCLUSION: The progression-free survival of patients who received systemic ICI therapy was 9.6 months, suggesting that ICI therapy might be effective in patients with pulmonary sarcomatoid carcinoma.

Association of Tumor PD-L1 Expression With Time on Treatment Using EGFR-TKIs in Patients With EGFR-Mutant Non-small Cell Lung Cancer.

BACKGROUND/AIM: The association between tumor PD-L1 expression and the rate of acquisition of the T790M mutation during treatment with first-/second-generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is a matter of study. This retrospective study was conducted to evaluate the association of tumor PD-L1 expression with the time on treatment under EGFR-TKIs in patients with EGFR-mutant non-small cell lung cancer (NSCLC), treated with first-/second-generation EGFR-TKIs. PATIENTS AND METHODS: We conducted a retrospective review of the medical charts of patients with EGFR-mutant NSCLC treated with first- /second-generation EGFR-TKIs. Time on treatment with EGFR-TKIs was defined as the sum of progression-free survival period (PFS) from the start of treatment with first- /second-generation EGFR-TKIs and the PFS from the start of osimertinib treatment after acquisition of the T790M mutation. Tumor PD-L1 expression was evaluated using the 22C3 antibody. RESULTS: Data of a total of 49 patients were analyzed, including 20 patients with negative tumor PD-L1 expression (tumor proportion score <1%) and 29 patients with positive tumor PD-L1 expression (tumor proportion score ≥1%). In the negative tumor PD-L1 expression group, the T790M mutation was detected in 12 (75%) of the 16 patients. In the positive tumor PD-L1 expression group, the T790M mutation was detected 6 (31.6%) out of the 19 patients in whom it was tested. The median (95% confidence interval) time on treatment with EGFR-TKIs was 21.7 (12.9-24.8) months and 12.3 (5.6-22.2) months in the negative and positive tumor PD-L1 expression groups, respectively. Analysis using a Cox proportional hazards model identified performance status and presence/absence of tumor PD-L1 expression as significantly associated with the time on treatment with EGFR-TKIs. CONCLUSION: EGFR-mutant NSCLC patients with negative tumor PD-L1 expression showed a higher rate of acquisition of the T790M mutation and implementation rate of osimertinib therapy, leading to a longer time on treatment with EGFR-TKI.

Case Series of Pleomorphic Carcinoma of the Lung Treated With Immune Checkpoint Inhibitors.

AIM: We report, herein, three cases of pleomorphic carcinoma of the lung treated with immune checkpoint inhibitors. Case 1: A 73-year-old man was diagnosed as having pleomorphic carcinoma of the lung and treated with pembrolizumab alone. However, he showed no response and died 4 months after the initiation of the treatment. Case 2: A 66-year-old man was diagnosed as having pleomorphic carcinoma of the lung. He was started on a combination regimen of pembrolizumab plus carboplatin plus nab-paclitaxel, and a remarkable response was observed. Case 3: A 49-year-old man was diagnosed as having pleomorphic carcinoma of the lung. He was started on pembrolizumab monotherapy as second-line treatment. Eleven months after the treatment initiation, computed tomography revealed the decrease of tumor diameter. CONCLUSION: Immune checkpoint inhibitor therapy is expected to improve the prognosis of patients with pleomorphic carcinoma of the lung.

Immune Checkpoint Inhibitor for Non-small Cell Lung Cancer With Negative or Low Tumor PD-L1 Expression.

Background/Aim: We conducted a retrospective analysis of the survival durations of 25 patients diagnosed as having non-squamous cell non-small cell lung cancer with negative or low tumor programmed death-ligand 1 (PD-L1) expression treated with immune checkpoint inhibitor (ICI) monotherapy. Patients and Methods: The progression-free (PFS) and overall (OS) survival were calculated from the initiation of ICI monotherapy. The association between the patient characteristics and the PFS was analyzed using Cox proportional hazards model. Results: The median PFS was 2.6 months, and the 12-month PFS rate was 9.3%. The median OS was 5.5 months, and the 12-month OS rate was 39.8%. A Cox proportional hazards model identified the neutrophil/lymphocyte ratio and presence of liver metastasis as being significantly associated with PFS. Conclusion: Our findings suggest that a subset of patients with non-squamous cell non-small cell lung cancer who show negative or low tumor PD-L1 expression could benefit from ICI monotherapy.