title: A new prognostic index for overall survival in malignant pleural mesothelioma: the rPHS (regimen, PS, histology or stage) index.
abstract: OBJECTIVE
  Existing prognostic indices for malignant pleural mesothelioma do not incorporate the recent advances in oncology care. The purpose of this study was to provide a prognostic index for overall survival in malignant pleural mesothelioma patients treated with chemotherapy with pemetrexed or best supportive care in the recent clinical setting.
  
  
  METHODS
  A retrospective cohort study was performed in two hospitals in Japan (2007-13). The primary outcome was overall survival. The Cox proportional hazards model was used for multivariable analyses to identify prognostic factors. A final model was chosen based on both clinical and statistical significance.
  
  
  RESULTS
  A total of 283 patients (chemotherapy: n = 228, best supportive care: n = 55) were enrolled in the study. On multivariate analysis, regimen including platinum plus pemetrexed, a performance status >0, non-epithelial histological type and Stage IV disease predicted poor overall survival in chemotherapy patients. As hazard ratios of individual risk factors were approximately similar, a prognostic index for overall survival was constructed by counting the risk factors. Median overall survival in chemotherapy patients decreased by each one-point increase in this count: 1030 days for zero; 658 days for one; 373 days for two; 327 days for three; 125 days for four. Internal validation using the bootstrapping technique showed robustness of the model (c-index, 0.677; 95% confidence interval, 0.624-0.729). Further, the discrimination was consistent in best supportive care patients (c-index, 0.799; 95% confidence interval, 0.725-0.874).
  
  
  CONCLUSIONS
  This novel index can provide clinicians and malignant pleural mesothelioma patients with a better framework for discussing prognosis at the time of diagnosis.
authors.affiliation: Department of Healthcare Epidemiology, Graduate School of Medicine and Public Health, Kyoto University, Kyoto Department of Respiratory Medicine, Hyogo Prefectural Amagasaki Hospital, Hyogo.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kataoka
authors.affiliation: Department of Healthcare Epidemiology, Graduate School of Medicine and Public Health, Kyoto University, Kyoto.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Cancer Center, Hyogo College of Medicine, Hyogo.
authors.forename: Taiichiro
authors.initials: T
authors.lastname: Otsuki
authors.affiliation: Department of Respiratory Medicine, Hyogo Prefectural Amagasaki Hospital, Hyogo.
authors.forename: Mariko
authors.initials: M
authors.lastname: Shinomiya
authors.affiliation: Division of Respiratory Medicine, Hyogo College of Medicine, Hyogo.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Terada
authors.affiliation: Department of Healthcare Epidemiology, Graduate School of Medicine and Public Health, Kyoto University, Kyoto Center for Innovative Research in Clinical Evaluative Science (CiRCLE), Fukushima Medical University, Hikarigaoka, Fukushima, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Fukuma
authors.affiliation: Department of Healthcare Epidemiology, Graduate School of Medicine and Public Health, Kyoto University, Kyoto.
authors.forename: Shin
authors.initials: S
authors.lastname: Yamazaki
authors.affiliation: Department of Respiratory Medicine, Hyogo Prefectural Amagasaki Hospital, Hyogo.
authors.forename: Masataka
authors.initials: M
authors.lastname: Hirabayashi
authors.affiliation: Division of Respiratory Medicine, Hyogo College of Medicine, Hyogo.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakano
authors.affiliation: Department of Healthcare Epidemiology, Graduate School of Medicine and Public Health, Kyoto University, Kyoto Center for Innovative Research in Clinical Evaluative Science (CiRCLE), Fukushima Medical University, Hikarigaoka, Fukushima, Japan fukuhara.shunichi.6m@kyoto-u.ac.jp.
authors.forename: Shunichi
authors.initials: S
authors.lastname: Fukuhara
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D008297:Male; D008654:Mesothelioma / Q000188:drug therapy / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D000086002:Mesothelioma, Malignant; D008875:Middle Aged; D009367:Neoplasm Staging; D010166:Palliative Care / Q000379:methods*; D010997:Pleural Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
keywords: best supportive care; malignant pleural mesothelioma; palliative care; pemetrexed; prognostic index