PD-L1 expression in gastroesophageal dysplastic lesions

• Published in: Virchows Archiv : an international journal of pathology Vol. 477; no. 1; pp. 151 - 156
• Main Authors: Fassan, Matteo, Brignola, Stefano, Pennelli, Gianmaria, Alberti, Giulia, Angerilli, Valentina, Bressan, Alessandra, Pellino, Antonio, Lanza, Cristiano, Salmaso, Roberta, Lonardi, Sara, Pucciarelli, Salvatore, Spolverato, Gaya, Scarpa, Marco, Realdon, Stefano, Farinati, Fabio, Luchini, Claudio, Rugge, Massimo, Loupakis, Fotios
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2020; Springer Nature B.V
• Subjects: Adenocarcinoma; Biomarkers; Brief Report; DNA repair; Dysplasia; Esophagus; Immunotherapy; Invasiveness; Lesions; Medicine; Medicine & Public Health; Mismatch repair; Pathology; PD-L1 protein; Repair; PD-L1; Biomarkers; Barrett’s esophagus; Dysplasia; Gastric carcinogenesis
• ISSN: 0945-6317; 1432-2307
• DOI: 10.1007/s00428-019-02693-8

Immunotherapy has been recently approved for gastric (GC) and gastroesophageal-junction adenocarcinomas (GEC), and PD-L1 immunohistochemical evaluation represents a promising predictive biomarker in this oncological setting. A series of 125 gastroesophageal dysplastic lesions (52 low-grade, 73 high-grade) was investigated for PD-L1 and DNA mismatch repair proteins status. PD-L1 was positive (combined positive score (CPS) ≥ 1) in 48 (31.0%) dysplastic lesions. A higher prevalence of PD-L1–positive cases was observed among esophageal specimens compared with gastric ones ( p  = 0.0003), in high-grade and adenocarcinoma samples in comparison with low-grade dysplasia ( p  < 0.0001), and in lesions with mismatch repair deficiency ( p  = 0.028). For 30 dysplastic samples, a synchronous matched invasive lesion (GC = 15, GEC = 15) was available and tested for PD-L1 expression; a discordant PD-L1 status was observed in 12/30 (40%) cases. A relatively high prevalence in PD-L1 positivity was observed among gastroesophageal dysplastic lesions and this should be taken into consideration for future therapeutic strategies based on this biomarker.