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.

Determinants of activity and efficacy of anti-PD1/PD-L1 therapy in patients with advanced solid tumors recruited in a clinical trials unit: a longitudinal prospective biomarker-based study

Immune-checkpoint inhibitors (ICI) have revolutionized the therapeutic landscape of cancer. However, optimal patient selection is still an unmet need. One-hundred-forty-six patients with metastatic cancer candidates to ICI at the Hospital Clinic of Barcelona Clinical Trials Unit were prospectively recruited in this observational study. Blood samples were collected at different timepoints, baseline LIPI score calculated and pre-ICI archived tissues retrieved to evaluate PD-L1, tumor-infiltrating lymphocytes (TILs) and PD1 mRNA levels. Tumor assessments were centrally reviewed by RECIST 1.1 criteria. Associations with overall response rates (ORR), durable clinical benefit (DCB), progression-free survival (PFS) and overall survival (OS) were performed with univariable/multivariable logistic and Cox regressions, where appropriate. At a median follow-up of 26.9 months, median PFS and OS were 2.7 and 12.9 months. Response rates were 17.8% with duration of response (DOR) of 4.4 months. LIPI score was independently associated with PFS (p = 0.025) and OS (p < 0.001). Immunotherapy-naïve status was independently associated with better PFS (p = 0.005). Time-to-best response (TTBR) and ORR (p < 0.001 both) were associated with better OS at univariate analysis. PFS and DOR were moderately correlated with OS (p < 0.001 both). A PD-L1 10% cut-off detected worse/best responders in terms of ORR (univariate p = 0.011, multivariate p = 0.028) and DCB (univariate p = 0.043). PD1 mRNA levels were strikingly associated to complete responses (p = 0.021). To resume, in our prospective observational pan-cancer study, baseline LIPI score, immunotherapy-naïve status, cancer type and RT before starting ICI were the most relevant clinical factors independently correlated with immunotherapy outcomes. Longer TTBR seemed to associate with better survival, while PD1 mRNA and PD-L1 protein levels might be tumor-agnostic predictive factors of response to ICI and should be furtherly explored.

Real-World Data on Pembrolizumab for Pretreated Non-Small-Cell Lung Cancer: Clinical Outcome and Relevance of the Lung Immune Prognostic Index

BACKGROUND

Pembrolizumab is licensed for the treatment of pre-treated and PD-L1 positive non-small cell lung cancer (NSCLC), but response is heterogeneous. In this context, the Lung Immune Prognostic Index (LIPI) has been proposed as tool to prognosticate outcome.

OBJECTIVE

To investigate the real-world efficacy and safety of pembrolizumab in pre-treated NSCLC patients and the clinical utility of LIPI for patients' selection.

PATIENTS AND METHODS

Patients with pre-treated NSCLC and PD-L1 ≥ 1% treated with pembrolizumab were included in this retrospective series. The LIPI was used to classify patients in 3 prognostics subgroups according to the pre-treatment dNLR (derived neutrophil to lymphocyte ratio) and LDH in blood. The prognostic impact of the LIPI on progression free survival (PFS) and overall survival (OS) was evaluated with Cox regression. The combined effect of LIPI and other relevant prognostic factors was explored with multivariate regression.

RESULTS

In total, 113 consecutive patients were included. Median (mPFS) and mOS was 4.3 (2.6-6.7) and 13.5 (10.3-17.7) months, respectively. Good-, intermediate-, and poor-LIPI was found in 54 (47.8%), 45 (39.8%), and 8 (7.1%) patients, respectively. Median PFS was 5.1 (2.8-9.1), 3.0 (2.5-6.8), and 1.4 (0.5-18.7) months, and mOS was 17.2 (12.0-26.4), 11.8 (8.4-17.1), and 3.7 (0.5-not calculable) months for good-, intermediate-, and poor-LIPI group, respectively. Patients with intermediate-LIPI and poor-LIPI had worse PFS versus good-LIPI, and statistically significant worse OS (p = 0.030 and p = 0.013, respectively). In the multivariate analysis, intermediate- versus good-LIPI (p = 0.190) was not independently associated to PFS or OS. Patients with both good-LIPI and high (≥ 50%) PD-L1 had better OS than all other subgroups defined by LIPI and PD-L1. Immune-related adverse events (irAEs) occurred in 47 (41.6%) patients (12.4% grade ≥ 3). In a time-varying analysis, irAEs were statistically associated with longer OS (HR 0.51, 0.31-0.84; p = 0.008).

CONCLUSION

In our series, the outcome of pembrolizumab in pre-treated NSCLC is consistent with the registration trial. Lung Immune Prognostic Index is a readily available tool able to prognosticate outcome, also in PD-L1-high patients. The positive association between irAEs and OS might aid decision making.

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.