Therapeutic outcome according to histologic subtype in 121 patients with malignant pleural mesothelioma

Abstract

One-hundred and twenty-one cases of malignant pleural mesothelioma (MPM) seen between 1986 and 1999 at the authors' Institution were reviewed. Histotype was epithelial in 88 patients (73%), sarcomatous in 21 (17%) and mixed in 12 (10%). Ninety-one patients received a treatment (38 palliative pleurectomy and no further therapy, 16 palliative pleurectomy followed by chemotherapy, 37 chemotherapy alone), while 30 were referred to supportive care only. Median survival of the whole population was 10.5 months. The 1-, 2- and 3-year survival were 40, 17 and 8%, respectively. Univariate analysis of subgroups showed that poor performance status (PS), non-epithelial histotype, Butchart stage>I and International Mesothelioma Interest Group (IMIG) stage>I were individually associated with lower survival. Patients receiving any therapy survived longer than patients treated with supportive care only (P=0.0004). Treatment modality had an independent prognostic value (P=0.00005), with a survival advantage for patients receiving surgery and adjuvant chemotherapy. Multivariate analysis confirmed the independent prognostic value of PS (P=0.001; HR=2.48) and treatment modality (P=0.003; HR=1.38). The prognostic role of PS (P=0.02) and treatment modality (P=0.01) was confirmed in the subset of patients with epithelial histology. On the contrary, therapy had no impact on survival in patients with sarcomatoid MPM (P=0.74). Despite the predicted bias of a retrospective non-randomized evaluation of treatment-related factors, patients with good PS and epithelial histology seemed to have a survival benefit from surgery or multimodality therapy, as opposite to patients with poor PS or non-epithelial histotype. However, these results must be confirmed in a larger prospective trial with uniform treatment.