Comprehensive Assessment of PD-L1 Staining Heterogeneity in Pulmonary Adenocarcinomas Using Tissue Microarrays: Impact of the Architecture Pattern and the Number of Cores.
Squamous cell carcinomas (8.1%) and large cell carcinomas (12.1%) showed high PD-L1 expression more commonly than adenocarcinomas (5.1%) but this was not statistically significant (p=0.072).
We observed in our series of 129 colorectal adenocarcinomas that PD-L1 expression occurred primarily in tumor-associated-immune cells and most prominently at the tumor-stroma-interface of the invasive front.
With a 1% cut-off value, PD-L1 protein expression showed a short overall survival duration in early stage adenocarcinoma with marginal significance (p = 0.05, Hazard ratio = 1.947).
Eligible patients were aged 20-79 years, had biliary tract adenocarcinoma (intrahepatic bile duct cancer, extrahepatic bile duct cancer, gallbladder cancer, or ampullary cancer), Eastern Cooperative Oncology Group performance status 0 or 1, adequate hepatic, renal, and haematological function, and tumour tissue samples for PD-L1 expression analysis.
A total of 369 patients with resected lung adenocarcinoma whose preoperative computed tomography findings were available for the examination of EB were analyzed for PD-L1 expression by immunohistochemistry and evaluated to determine the association between PD-L1 expression and EB-related adenocarcinomas.
Validation cohorts including our biobank confirmed that the AXL expression significantly correlated with expression of genes encoding programmed death-ligand1 (PD-L1) and CXC chemokine receptor 6 (CXCR6) in lung adenocarcinoma, especially in epidermal growth factor receptor (EGFR) mutation-positive adenocarcinoma.
Together with PD-L1 expression, EGFR mutation status is an important factor to predict the efficacy of PD-1/PD-L1 inhibitors in patients with pulmonary adenocarcinoma.
When analyzed as either a continuous or a dichotomous variable, the mean number of tumor cells expressing PD-L1 (<i>p</i> = 0.012) and the percentage of tumor cells expressing PD-L1 were higher in <i>ALK</i>-positive ADC than in <i>EGFR-mutated</i> ADC or WT (non-<i>EGFR</i>-mutated and non-<i>KRAS</i>-mutated) NSCLC.
Immunohistochemistry was performed for the CSC markers Lgr5 and SOX2 and the immune-associated markers CD8, Foxp3 and PD-L1 in 79 cases of endoscopically-excised rectal lesions, ranging from low grade adenoma (LG) to invasive adenocarcinoma (AdCa).
These results show that the two subtypes of adenocarcinoma of the AOV exhibit significant differences in tumoral PD-L1 expression and intratumoral CD8<sup>+</sup> T lymphocyte density, which might contribute to their distinct clinical features.
A 73-year-old women known for myositis, Crohn's disease, and hypothyroidism and diagnosed with PD-L1 positive stage IV pulmonary adenocarcinoma is treated with Pembrolizumab.
Invasive mucinous adenocarcinoma was significantly associated with <i>KRAS</i> and <i>ALK</i> aberrations (both P<0.001), while solid predominant adenocarcinoma was associated with <i>ROS1</i> translocations (P=0.036) and PD-L1 expression (P<0.001).
Our results support that the highest PD-L1 expression on tumor cells occurs in SCC patients and in adenocarcinoma patients without common, druggable genetic abnormalities.