1. Prognostic value of PD-L1 expression in bronchopulmonary neuroendocrine tumours
- Author
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Jörg Sänger, Erik Rösner, Amelie Lupp, Elisa Neubauer, and Daniel Kaemmerer
- Subjects
0301 basic medicine ,PD-L1 ,carcinoid ,Endocrinology, Diabetes and Metabolism ,Malignancy ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,CXCR4 ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,antibody ,PD-1 ,Internal Medicine ,medicine ,neuroendocrine tumour ,Lung cancer ,Lymph node ,large cell neuroendocrine carcinoma ,lcsh:RC648-665 ,biology ,business.industry ,Research ,Chromogranin A ,Cancer ,Large cell neuroendocrine carcinoma of the lung ,medicine.disease ,lung cancer ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,immunohistochemistry ,Cancer research ,biology.protein ,small cell lung cancer ,business - Abstract
Programmed death protein 1 (PD-1) and its ligand, PD-L1, have emerged as promising therapeutic targets for many types of cancer that overexpress PD-L1. However, data on PD-L1 expression levels in bronchopulmonary neuroendocrine neoplasms (BP-NEN) are limited and contradictory. In the present study, a total of 298 archived, formalin-fixed, paraffin-embedded BP-NEN samples from 97 patients diagnosed with typical carcinoid (TC), atypical carcinoid (AC), small cell lung cancer (SCLC), or large cell neuroendocrine carcinoma of the lung (LCNEC) were evaluated for PD-L1 expression by immunohistochemistry using the highly sensitive monoclonal anti-PD-L1 antibody 73-10. PD-L1 expression levels were semiquantitatively estimated by tumour grading. Of the 298 BP-NEN samples, 85% were positive for PD-L1 expression. PD-L1 immunostaining predominantly localized to the plasma membrane of both tumour cells and tumour-infiltrating immune cells. SCLC and LCNEC exhibited significantly higher PD-L1 expression levels than TC or AC. PD-L1 expression levels were also higher in patients with lymph node or distant metastases, in patients who smoked, and in patients who died during the follow-up period. Moreover, PD-L1 expression levels correlated positively with tumour grading, Ki-67 index and the expression of the chemokine receptor CXCR4 and negatively with the levels of somatostatin receptor 1 and chromogranin A. High tumour PD-L1 levels were associated with poor patient outcomes. In conclusion, PD-L1 expression is common in BP-NEN, increases with malignancy, and is associated with poor prognosis. Therefore, targeting the PD-1/PD-L1 axis could be a promising strategy for treating BP-NEN. PD-L1 may also represent a useful prognostic biomarker for this tumour entity.
- Published
- 2020