Even though some recent studies have found the ratio of neutrophils to lymphocytes (NLR) in the blood to be a poor prognostic indicator for cancer, Chinese researchers say it may still be effective for planning mesothelioma treatment and qualifying patients for clinical trials.
The Prognostic Role of NLR
The team of scientists from Sichuan University conducted a meta-analysis of 10 studies on the prognostic role of NLR in pleural mesothelioma. The study included more than 1500 mesothelioma patients. Their findings indicate that there is a role for NLR in predicting outcomes and determining which mesothelioma therapies are likely to be most effective.
“The elevated NLR was detected to be associated with a poor overall survival,” writes study author Nan Chen with the West China School of Medicine at Sichuan University. “The significant prognostic roles of NLR were also indicated in subgroup analysis.”
When the researchers broke the findings down further, they found that NLR level was more closely associated with mesothelioma histological subtype (i.e., epithelioid, sarcomatoid, or biphasic) than with gender, stage or performance status.
The Chinese researchers conclude that NLR could not only be a potential prognostic tool for malignant pleural mesothelioma but could also be used to categorize patients for treatment.
Neutrophils, Lymphocytes, and Mesothelioma
Because it is associated with inflammation in the body, the neutrophil-to-lymphocyte ratio provides a snapshot of the status of the immune system, which is responsible for helping the body fight cancer and suppress new tumors. NLR is calculated by dividing the number of neutrophils by the number of lymphocytes in a blood or tissue sample.
Mesothelioma researchers in England have recently reached similar conclusions about NLR. Earlier this year, researchers at the Royal Marsden Hospital in London unveiled their mesothelioma-specific prognostic scoring system which found that mesothelioma survival in clinical trials was lower in patients with NLR scores higher than 3.
A separate 2015 study of 73 pleural mesothelioma patients in Southwest England calculated a median mesothelioma survival increase of 200 days in patients with an NLR score lower than 4.
Other recently identified mesothelioma biomarkers with prognostic potential include c-MET expression (associated with blood vessel formation for the tumor), ki-67 ratios (associated with cancer cell proliferation), and blood levels of a protein called fibulin-3.
Source: Chen, N, et al, “Prognostic significance of neutrophil-to-lymphocyte ratio in patients with malignant pleural mesothelioma: a meta-analysis”, February 2017, Oncotarget, Epub head of print