Factors associated with survival in a large series of patients with malignant pleural mesothelioma in New South Wales

Abstract

Background:Although the prognosis of most patients presenting with malignant pleural mesothelioma (MPM) is poor, a small proportion survives long term. We investigated factors associated with survival in a large patient series.Methods:All patients registered with the NSW Dust Diseases Board (2002–2009) were included in an analysis of prognostic factors using Kaplan–Meier and Cox regression analysis. On the basis of these analyses, we developed a risk score (Prognostic Index (PI)).Results:We identified 910 patients: 90% male; histology (epithelioid 60% biphasic 13% sarcomatoid 17%); stage (Tx-I-II 48% III-IV 52%); and calretinin expression (91%). Treatment: chemotherapy(CT) 44%, and extrapleural-pneumonectomy (EPP) 6%. Median overall survival (OS) was 10.0 months. Longer OS was associated with: age <70 (13.5 vs 8.5 months; P<0.001); female gender (12.0 vs 9.9 months; P<0.001); epithelioid subtype (13.3 vs 6.2 months; P<0.001); ECOG status 0 (27.4 vs 9.7 months; P=0.015), calretinin expression (10.9 vs 5.5 months; P<0.001); neutrophil–lymphocyte ratio (NLR) <5 (11.9 vs 7.5 months; P<0.001); platelet count <400 (11.5 vs 7.2 months; P<0.001); and normal haemoglobin (16.4 vs 8.8 months; P<0.001). On time-dependent analysis, patients receiving pemetrexed-based chemotherapy (HR=0.83; P=0.048) or EPP (HR=0.41; P<0.001) had improved survival. Age, gender, histology, calretinin and haematological factors remained significant on multivariate analysis. In all, 24% of patients survived >20 months: 16% of these receiving EPP, and 66% CT. The PI offered improved prognostic discrimination over one of the existing prognostic models (EORTC).Conclusions:We identified calretinin expression, age, gender, histological subtype, platelet count and haemoglobin level as independent prognostic factors. Patients undergoing EPP or pemetrexed-based chemotherapy demonstrated better survival, but 84% and 34% of long survivors, respectively, did not receive radical surgery or chemotherapy.

Patterns in the incidence, mortality and survival of malignant pleural and peritoneal mesothelioma, New South Wales, 1972–2009

“…18,22,23 Linton et al (2014) showed that people with non-epithelioid subtype had a two-fold greater mortality risk than people with epithelioid disease, a hazard rate ratio of 2.0 (95%CI 1.62, 2.48).…”

“…[16][17][18] These studies may be subject to selection bias due to the fact that these data exclude people with non-occupational asbestos exposures, possibly excluding up to 30% of all MPM cases diagnosed during the relevant calendar period in NSW. 18 The aim of this study was to assess malignant mesothelioma incidence, mortality and survival by tumour location and histological subtype using more up-to-date cancer registration data, and to compare differences in 5-year relative survival by subgroup. We hypothesised that the incidence of malignant mesothelioma had increased over time, with variation by tumour location.…”

“…Notably, these factors were not significant when measuring median survival time in this patient series. 18 A potential limitation of our study is that we did not have available information about a person's asbestos exposure history. However, we consider that measuring population-based incidence, survival and mortality estimates are valid in their own right.…”

Novel systemic therapy against malignant pleural mesothelioma

“…These patients should be considered for systemic therapy. Even with treatment, MPM has a poor prognosis with median survival of approximately one-year and cure is very rare (33)(34)(35). The limited efficacy of therapy for MPM highlights the need to develop more effective therapies for MPM which is challenged by the heterogeneity of MPM (with three pathological subtypes), the relatively low incidence of the disease, and the degree of difficulty with assessment of response.…”

Overexpressed genes in malignant pleural mesothelioma: implications in clinical management

“…Calretinin is considered the most sensitive and specific positive mesothelioma marker, above all for epithelioid mesothelioma subtype (65). Also the prognostic role of calretinin has been explored: in several studies higher calretinin expression was observed in tumours with more favourable prognosis (58)(59)(60)(61). Lately the correlation of increased calretinin expression with a better survival has been confirmed and its higher expression has been also associated with epithelioid histology subtype (62).…”