1. Heterogeneity of PD-L1 Expression in Lung Mixed Adenocarcinomas and Adenosquamous Carcinomas
- Author
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Zito Marino F., Rossi G., Montella M., Botti G., De Cecio R., Morabito A., La Manna C., Ronchi A., Micheli M., Salatiello G., Micheli P., Rocco D., Accardo M., Franco R., ZITO MARINO, Federica, Zito Marino, F., Rossi, G., Montella, M., Botti, G., De Cecio, R., Morabito, A., La Manna, C., Ronchi, A., Micheli, M., Salatiello, G., Micheli, P., Rocco, D., Accardo, M., Franco, R., and ZITO MARINO, Federica
- Subjects
0301 basic medicine ,PD-L1 ,Male ,Lung Neoplasms ,Biopsy ,Adenocarcinoma ,B7-H1 Antigen ,Pathology and Forensic Medicine ,03 medical and health sciences ,Carcinoma, Adenosquamous ,0302 clinical medicine ,Cytology ,PD-1 ,Carcinoma ,medicine ,Biomarkers, Tumor ,Humans ,Epidermal growth factor receptor ,Lung cancer ,Aged ,Aged, 80 and over ,Lung ,biology ,medicine.diagnostic_test ,business.industry ,Middle Aged ,medicine.disease ,lung adenocarcinoma ,Immunohistochemistry ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,Biomarker (medicine) ,Surgery ,Female ,immunotherapy ,lung adenosquamous carcinoma ,Anatomy ,business - Abstract
Immune checkpoint inhibitors against programmed cell death protein 1/programmed death-ligand 1 (PD-L1) have proven to be remarkably effective in non-small cell lung cancer. PD-L1 represents a predictive biomarker in lung cancer, although its heterogenous expression represents an emerging challenge for accurate biomarker-based patient selection. Lung adenocarcinomas (ADCs) show a high rate of intratumor morphologic heterogeneity that may reflect a heterogenous molecular and immunophenotypic profile. The aim of our study was to analyze the expression of PD-L1 in different intratumor subtypes and/or growth patterns in a series of mixed adenocarcinomas (mADCs) and adenosquamous lung carcinomas (AdSqLCs). As many as 73 mADCs and 6 AdSqLCs were selected. Comprehensive histologic subtyping was performed, and PD-L1 expression was assessed by immunohistochemistry assay using different primary antibodies and automated immunostainers. Overall, PD-L1 expression was observed in 37 of 79 cases (39.2%) (31 mADCs and all AdSqLCs). PD-L1 expression was heterogenous in 22 of 37 PD-L1-positive cases (23.2% mADC and 83% AdSqLC). PD-L1 expression was observed more frequently in ADC with solid pattern. Heterogeneity of PD-L1 expression was significantly related to the presence of micropapillary (P=0.028) and solid (P=0.017) patterns. All PD-L1-positive cases were epidermal growth factor receptor wild-type, 2 cases harbored concomitantly PD-L1 expression and ALK rearrangement. Our data suggest that PD-L1 expression is quite heterogenous in mADCs and AdSqLCs, partly contributing to explaining the discrepant results between biopsy and surgical resections and discordant clinical effectiveness in regard to PD-L1-positive or negative ADC diagnosed on cytology/small biopsy.
- Published
- 2019