High blood neutrophil-to-lymphocyte ratio is an indicator of poor prognosis in malignant mesothelioma patients undergoing systemic therapy.
OBJECTIVE
Asbestos-induced chronic inflammation is implicated in the pathogenesis of malignant mesothelioma (MM). We have investigated blood neutrophil-to-lymphocyte ratio (NLR), an index of systemic inflammation, as a prognostic factor in MM patients.


METHODS
Patients with MM who had systemic therapy at participating institutes were studied. Potential prognostic factors such as age, gender, performance status, histologic subtype, and baseline laboratory parameters, including NLR, were analyzed. Overall survival from commencement of therapy was determined by the Kaplan-Meier method. Multivariate analyses using Cox Regression model were performed with significant factors (P ≤ 0.05) to determine their independent effect.


RESULTS
A total of 173 MM patients undergoing systemic therapy including 119 patients receiving first-line therapy and 54 patients receiving second- or third-line therapy were included in this retrospective evaluation. Forty-two percent of patients had an elevated NLR at baseline. The following variables were predictive of survival: female gender (P = 0.044), epithelioid histologic subtype (P < 0.001), baseline white blood cell count less than 8.3 × 10⁹/L (P = 0.008), baseline platelet count 400 × 10⁹/L or less (P = 0.05), and NLR of 5 or less (P < 0.001). After multivariate analysis, histologic epithelioid subtype [hazard ratio (HR) = 2.0; 95% confidence interval (CI) = 1.3-2.9; P = 0.001], and NLR less than 5 (HR = 2.7; 95% CI = 1.8-3.9; P < 0.001) remained independent predictors. The 1-year survival rate was 60% versus 26%, whereas the 2-year survival rate was 34% versus 10% for NLR less than 5 and 5 or greater, respectively. In the separate analyses of chemotherapy-naive and previously treated patient groups, NLR was an independent predictor of survival in both groups.


CONCLUSIONS
Our results indicate that NLR is an independent predictor of survival for patients with MM undergoing systemic therapy.
Department of Medical Oncology, Sydney Cancer Centre, Australia.
Steven C H
SC
Kao
Nick
N
Pavlakis
Rozelle
R
Harvie
Janette L
JL
Vardy
Michael J
MJ
Boyer
Nico
N
van Zandwijk
Stephen J
SJ
Clarke
D000328:Adult; D000368:Aged; D000465:Algorithms; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D007958:Leukocyte Count; D008214:Lymphocytes / Q000473:pathology*; D008297:Male; D008654:Mesothelioma / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D008875:Middle Aged; D009367:Neoplasm Staging; D009504:Neutrophils / Q000473:pathology*; D010997:Pleural Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D016019:Survival Analysis