Neutrophil-to-Lymphocyte Ratio (NLR) in NSCLC, Gastrointestinal, and Other Solid Tumors: Immunotherapy and Beyond

In the era of immunotherapy, identifying biomarkers of immune system activation has become a high-priority challenge. The blood neutrophil-to-lymphocyte ratio (NLR) has been largely investigated as a biomarker in several cancer types. NLR values have been shown to mirror the tumor-induced inflammatory status and have been demonstrated to be a reliable prognostic tool across stages of disease and therapeutic approaches. When integrated with other biomarkers of response to immunotherapy, such as PD-L1, tumor mutational burden, and tumor-associated immune cells, the NLR may allow to further stratify patients with different likelihoods of deriving a significant clinical benefit. However, despite its accessibility, low cost, and easy interpretation, the NLR is still poorly used as a prognostic tool in daily clinical practice. In this review, we analyze the role of the NLR in defining the relationship between cancer and the immune system, its usefulness in daily clinical practice, and its relationship with other established or emerging biomarkers of immunotherapy outcomes.

The Prediction Potential of the Pretreatment Lung Immune Prognostic Index for the Therapeutic Outcomes of Immune Checkpoint Inhibitors in Patients With Solid Cancer: A Systematic Review and Meta-Analysis

Background

The lung immune prognostic index (LIPI) is recently developed to predict immune checkpoint inhibitors (ICIs) treatment outcomes for non-small cell lung cancer. However, its predictive value for other types of cancer remained unclear. This meta-analysis aimed to evaluate the association between pretreatment LIPI score and therapeutic outcomes in cancer patients treated with ICIs.

Methods

We searched PubMed, Cochrane Library literature databases and EMBASE for abstracts and full-text articles published from the inception of the database until 16th, Nov 2020. Meta-analyses were performed separately for progression-free survival (PFS) and overall survival (OS) by using the random-effects model.

Results

A total of 12 studies involving 4883 patients receiving ICIs treatment were identified for the primary analysis. The pooled results implied that compared with good LIPI score groups, patients with poor or intermediate LIPI score were significantly associated with worse OS (HR=3.33, 95%CI 2.64-4.21, P < 0.001, I² = 64.2%; HR=1.71, 95%CI 1.43-2.04, P < 0.001, I² = 43.6%, respectively) and PFS (HR=2.73,95%CI 2.00-3.73, P < 0.001, I² = 78.2%; HR=1.43, 95%CI 1.28-1.61, P < 0.001, I² = 16.3%, respectively). Also, for 1873 patients receiving chemotherapy, a poor LIPI score was significantly associated with worse OS (HR=2.30, 95%CI 1.73-3.07, P < 0.001; I² = 56.2%) and PFS (HR=1.92,95%CI 1.69-2.17; P < 0.001; I² = 0.0%) compared with good LIPI score groups.

Conclusions

A good LIPI score was significantly correlated with improved OS and PFS in cancer patients receiving ICIs or chemotherapy, regardless of the types of cancer.

The LIPI score and inflammatory biomarkers for selection of patients with solid tumors treated with checkpoint inhibitors

Over the last decade, immune checkpoint inhibitors (ICI) have completely changed the treatment strategy and the prognosis of several solid cancer types. There is a lack of biomarkers to differ between responders and non-responders to these therapies. The development of biomarkers for immunotherapy has been mainly focused on tumor-related factors. The role of PD-L1 expression or tumor mutational burden (TMB) as potential predictive biomarkers for ICI efficacy is not universal and remains controversial. Moreover, leukocyte and neutrophil counts in blood samples have been used to develop clinical indicators of systemic inflammation like the neutrophil to lymphocyte ratio (NLR) and derived neutrophil to lymphocyte ratio (dNLR) based on the host immunologic status to respond against cancer cells by the immune-effectors. The Lung Immune Prognostic Index (LIPI) score have been developed as a reliable tool to assess the risk stratification of patients with cancer and to guide treatment decisions in the era of personalized cancer treatments. We review the clinical evidence supporting the use of the LIPI index as a clinically valuable biomarker for patients with NSCLC and other solid tumor types, treated with immunotherapy.