Survival in Good Performance Malignant Pleural Mesothelioma Patients; Prognostic Factors and Predictors of Response

Purpose: Malignant pleural mesothelioma (MPM) has a poor prognosis in general. Here we sought to evaluate prognostic factors and predictors of response to chemotherapy in good performance (PS=0-I) patients. Methods: We retrospectively reviewed our database and enrolled patients with MPM who received platinum containing chemotherapy (2012-2014). Clinico-pathological and laboratory data were retrieved and Cox and logistic regression multivariate analyses (MVA) were respectively used to identify predictors of survival and response to chemotherapy. Comparison of good vs poor performance status (PS≥II) was accomplished using the Chi (X2) test. Kaplan­Meier survival curves were also obtained and propensity-score matching was performed for survival comparison. Results: Among 114 patients listed during the study period, 82 had good PS=0-I (median age 45years, 43 men, 30 smokers, median weight=77Kg, pretreatment haemoglobin (Hb) level=12g/dL, platelet count=372,000/µL, leukocytes=9,700/µL, neutrophils=6,100/µL, lymphocytes=1,890/µL and neutrophil/lymphocyte ratio (NLR)=3.60 ). Some 65 had asbestosis, 23 had chronic disease, 55 (67.1%) were responders to platinum containing first line chemotherapy. A total of 49 (59.8%) had epithelial MPM. Median-OS and PFS in good PS cases were 17 and 9 months, respectively, as compared to 16 and 8 months for the poor PS group. After matching, better OS was observed among good PS vs poor PS patients (p=0.024) but there was no PFS difference (p=0.176). Significant decrease in PFS was observed among those with advanced nodal N disease (median PFS in N0 and N+ was 10 and 5 months, respectively), non-responders (p=0.012), NLR (p=0.026) and those with an epithelial pathology (p=0.062). MVA demonstrated that advanced (N) status (p=0.015), being a non-responder (p<0.001), NLR (p=0.015) and smoking (p=0.07) adversely affected the prognosis. The only predictor of response was absence of metastasis (M0; p=0.04). Conclusions: In addition to previously recognized factors, like nodal status, response, smoking and NLR, better median survival was evident in our patients with a good PS. Early detection before development of metastasis warrants greater focus to allow better responses to be obtained.