Thoracic stop-flow perfusion in the treatment of refractory malignant pleural mesothelioma: a phase I-II evaluation/trial

Malignant pleural mesothelioma (MPM) is an aggressive treatment-resistant tumor with a median survival from diagnosis of 12 months. Although multimodality protocols that combine aggressive surgery and adjuvant chemotherapy or radiotherapy have shown improved survival in selected cases, the majority of patients with MPM are not suitable for radical surgery due to advanced stage and comorbid medical illness. For these patients combination chemotherapy with Pemetrex and Cisplatin should be considered for first line palliative chemotherapy. The therapeutic options available to patients with MPM resistant or refractory to systemic chemotherapy are very limited. Thoracic "stop-flow" perfusion (TSP) is a semi-invasive loco-regional drug delivery system that, limiting the circulation to the thorax during the anticancer agent's infusion, claims the advantage of reaching high drug concentration at the tumor site while maintaining a low systemic toxicity. The aim of this phase I-II study was to evaluate the toxicity profile and efficacy of two different platinum-based combined regimens--cisplatin plus mitomycin-C (MMC) and cisplatin plus melphalan (L-PAM)--administered using TSP technique in patients with advanced or recurrent MPM who had refractory disease after systemic first line chemotherapy. Patients with histologically proven unresectable stage II-III MPM entered this trial. Between January 1995 and December 2001, 27 patients were enrolled in the study and submitted to TSP using the two different chemotherapy cisplatin based regimens: 12 patients received cisplatin 100 mg/m2 plus MMC 20 mg/m2 (MMC arm) and 15 cisplatin 100 mg/m2 plus L-PAM 50 mg/m2 (L-PAM arm). Objective responses were assessed by CT-scan 30 and 60 days after the end of treatment in all 27 enrolled patients. Two patients (7.4%) achieved a complete response, 2 (7.4%) a partial response and 4 (14.8%) a minor response. The remaining 19 patients (70.3%) showed a stable disease. No patients developed progression of the disease following the first TSP. The overall median time to progression was 8.9 months (range 1-41). The median survival time for all patients from the beginning of regional chemotherapy was 16.6 months, with a 1-year survival rate of 62.9%, a 2-year survival rate of 18.5%, and a 3-year survival rate of 7.4%. Our data show that TSP is a relatively effective second-line treatment in patients with progressive disease after systemic chemotherapy, with a low rate of major complications and treatment-related toxicity.