Kazuki Takada1, Gouji Toyokawa2, Tatsuro Okamoto3, Takaki Akamine3, Shinkichi Takamori3, Masakazu Katsura3, Takatoshi Fujishita3, Fumihiro Shoji3, Yoshinao Oda4, Yoshihiko Maehara3. 1. Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. 2. Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan gouji104kawa@gmail.com. 3. Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. 4. Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Abstract
BACKGROUND: Programmed cell death ligand 1 (PD-L1) expression in lung cancer appears to be important in immunotherapy, as its expression can predict responses to programmed cell death-1 (PD-1)-blocking antibodies. However, a definitive antibody and cut-off value for PD-L1 expression are urgently needed. MATERIALS AND METHODS: The PD-L1 expression in 40 surgically resected small cell lung cancer (SCLC) specimens was evaluated by immunohistochemistry (IHC) with three different antibodies: clones E1L3N, 28-8, and SP142, and using three different evaluations: the Allred score, 1% cut-off, and 5% cut-off. RESULTS: The percentage of tumors with positive PD-L1 expression was inconsistent in the IHC evaluations using the Allred score and 1% cut-off. However, the IHC evaluations using the 5% cut-off showed similar rates of expression using the three different antibodies. CONCLUSION: The results of this study provided detailed evidence on the frequency of PD-L1 expression in surgically resected SCLC, which may be a useful reference for identifying patients with PD-L1-expressing SCLC. Copyright
BACKGROUND:Programmed cell death ligand 1 (PD-L1) expression in lung cancer appears to be important in immunotherapy, as its expression can predict responses to programmed cell death-1 (PD-1)-blocking antibodies. However, a definitive antibody and cut-off value for PD-L1 expression are urgently needed. MATERIALS AND METHODS: The PD-L1 expression in 40 surgically resected small cell lung cancer (SCLC) specimens was evaluated by immunohistochemistry (IHC) with three different antibodies: clones E1L3N, 28-8, and SP142, and using three different evaluations: the Allred score, 1% cut-off, and 5% cut-off. RESULTS: The percentage of tumors with positive PD-L1 expression was inconsistent in the IHC evaluations using the Allred score and 1% cut-off. However, the IHC evaluations using the 5% cut-off showed similar rates of expression using the three different antibodies. CONCLUSION: The results of this study provided detailed evidence on the frequency of PD-L1 expression in surgically resected SCLC, which may be a useful reference for identifying patients with PD-L1-expressing SCLC. Copyright
Authors: Georgia Karpathiou; Francois Casteillo; Jean-Baptiste Giroult; Fabien Forest; Pierre Fournel; Alessandra Monaya; Marios Froudarakis; Jean Marc Dumollard; Jean Michel Prades; Michel Peoc'h Journal: Oncotarget Date: 2017-03-21