Neutrophil-to-Lymphocyte Ratio Predicts Development of Immune-Related Adverse Events and Outcomes from Immune Checkpoint Blockade: A Case-Control Study

• Main Authors: Pei Yi Lee, Kellynn Qi Xuan Oen, Grace Rui Si Lim, Juanda Leo Hartono, Mark Muthiah, Daniel Q. Huang, Felicia Su Wei Teo, Andrew Yunkai Li, Anselm Mak, Nisha Suyien Chandran, Chris Lixian Tan, Peiling Yang, E Shyong Tai, Kay Wei Ping Ng, Joy Vijayan, Yee Cheun Chan, Li Ling Tan, Martin Beng-Huat Lee, Horng Ruey Chua, Wei Zhen Hong, Eng Soo Yap, Dawn K. Lim, Yew Sen Yuen, Yiong Huak Chan, Folefac Aminkeng, Alvin Seng Cheong Wong, Yiqing Huang, Sen Hee Tay
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Cancers
• Subjects: neutrophil-to-lymphocyte ratio; immunotherapy; immune-related adverse events; survival
• Online Access: https://www.mdpi.com/2072-6694/13/6/1308

The utility of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) utility in predicting immune-related adverse events (irAEs) and survival have not been well studied in the context of treatment with immune checkpoint inhibitors (ICIs). We performed a case-control study of cancer patients who received at least one dose of ICI in a tertiary hospital. We examined NLR and PLR in irAE cases and controls. Logistic and Cox regression models were used to identify independent risk factors for irAEs, progression-free survival (PFS), and overall survival (OS). The study included 91 patients with irAEs and 56 controls. Multiple logistic regression showed that NLR < 3 at baseline was associated with higher occurrence of irAEs. Multivariate Cox regression showed that development of irAEs and reduction in NLR from baseline to week 6 were associated with longer PFS. Higher NLR values at baseline and/or week 6 were independently associated with shorter OS. A reduction in NLR from baseline to week 6 was associated with longer OS. In this study of cancer patients treated with ICIs, NLR has a bidirectional relationship with adverse outcomes. Lower NLR was associated with increased occurrence of irAEs while higher NLR values were associated with worse clinical outcomes.