The Prognostic Significance of Peripheral Blood Biomarkers in Patients With Advanced Non-Small Cell Lung Cancer Treated With Pembrolizumab: A Clinical Study.

Systemic inflammation has long been associated with poor outcomes in many types of solid tumors. Peripheral blood biomarkers, such as absolute lymphocyte count (ALC) and the ratio of absolute neutrophil count to absolute lymphocyte count (ANC/ALC), have been shown to be immune-inflammatory parameters highlighting an individual's immune status. The prognostic role of ALC and ANC/ALC on overall survival (OS) was examined in patients with advanced non-small cell lung carcinoma (NSCLC) receiving pembrolizumab. Of a total of 239 patients, 52% were male, with a median age of 67 years (interquartile range [IQR], 59-73). Most patients had a diagnosis of adenocarcinoma (76%), with stage IV disease (82%). PD-L1 expression was >50% in 44% of the patients. The median time on treatment with pembrolizumab was 5.8 months (IQR, 2.9-12.7). An ANC/ALC <5 was associated with improved OS at initiation of pembrolizumab (P = .002), whereas an ALC >1.4 deciliter (dL) trended toward improved OS compared with ALC <1.4 dL (P = .053). After adjusting for potential cofounders with a multivariate analysis, a baseline ANC/ALC of 5 or higher was associated with a significantly increased risk of death (HR, 1.93; 95% CI, 1.27-2.93; P = .002). An ANC/ALC <5 at the time of initiation of treatment with pembrolizumab was associated with improved OS in patients with advanced NSCLC. The median ALC and ANC/ALC were significantly lower after 6 weeks of treatment with pembrolizumab.