Siba El Hussein, L Jeffrey Medeiros, Stephen K Gruschkus, Peng Wei, Ellen Schlette, Hong Fang, Fatima Zahra Jelloul, Wei Wang, Warren Fiskus, Rashmi Kanagal-Shamanna, Sanam Loghavi, Hong Yang, Shaoying Li, Jie Xu, Zhenya Tang, Beenu Thakral, Nitin Jain, William G Wierda, Keyur Patel, Kapil N Bhalla, Joseph D Khoury
Immune checkpoint inhibitors (PD-1 inhibitors) have shown clinical activity in Richter transformation-diffuse large B-cell lymphoma variant (RT-DLBCL), thus providing for a novel therapeutic approach. The study group consists of 64 patients with RT-DLBCL. Expression of PD-1, PD-L1, CD30, and microsatellite instability (MSI) status (hMLH1, hMSH2, hMSH6, PMS1) was assessed using immunohistochemistry. EBV-encoded RNA (EBER) was evaluated using colorimetric in situ hybridization. PD-1 and PD-L1 expression levels were categorized on the basis of tumor cell expression as follows: negative (< 5%), positive to low-positive (5-50%), or high-positive (> 50%)...
March 3, 2023: Virchows Archiv: An International Journal of Pathology