Prognostic factors according to the treatment schedule in malignant pleural mesothelioma

In this study, we aimed to investigate the factors affecting the survival of patients with malignant pleural mesothelioma (MPM) according to their treatment schedules, including those treated with best supportive care, chemotherapy, and multimodality therapy.

We evaluated 235 patients with MPM. The patients were classified into three groups according to their treatment schedules: the best supportive care group, the chemotherapy group, and the multimodality therapy group. Prognostic factors were determined for all patients and for the three groups by univariate and multivariate analyses. However, the effectiveness of treatment schedules as a prognostic factor was not evaluated in this study.

After adjusting for therapy in a Cox model, a Karnofsky Performance Status (KPS) < or = 70, a right side tumor, serum lactate dehydrogenase >500 IU(-1), a nonepithelial subtype, and stage 3 to 4 disease were determined by multivariate analyses to be unfavorable prognostic factors for all the patients. A KPS < or = 70, serum lactate dehydrogenase >500 IU(-1), a nonepithelial subtype, and stage 3 to 4 disease were associated with a poor prognosis for the best supportive care group. The single unfavorable prognostic factor for the chemotherapy group was a KPS < or = 70. A right side tumor and a nonepithelial subtype were associated with a poor prognosis for the multimodality therapy group.

The patients with an epithelial subtype, a good KPS, and an early-stage tumor had a good prognosis, even if they did not receive any treatment. The only prognostic factor for the chemotherapy group was KPS. The histologic subtype and stage of the tumor were not related to the prognosis in this group. A mixed subtype and a right side tumor were unfavorable prognostic factors for the multimodality therapy group. These findings may be useful in counseling patients and in planning further studies.