Current Therapy For Mesothelioma

Malignant pleural mesothelioma is locally aggressive, invasive, and almost universally fatal.

INTRODUCTION

Mesotheliomas of the pleural cavity are relatively rare tumors. Generally, two types of pleural tumors can be referred to as mesotheliomas. The less common is the solitary (or localized) fibrous tumor of the pleura, previously known as "benign mesothelioma." This slow-growing, commonly benign, well- circumscribed tumor is pedunculated on a pleural-based pedicle and often is cured by resection. The tumor appears to originate from submesothelial rather than mesothelial or epithelial cells. The more common variety is the diffuse malignant pleural mesothelioma (DMPM), a true mesothelial malignancy that is locally aggressive, invasive, and almost universally fatal. This multicentric tumor infiltrates the pleural space, results in a pleural effusion, and mechanically compresses the surrounding structures. Though distant metastatic lesions may be seen in up to 30% of cases in autopsy series, most patients die of locoregional invasion and compression of vital structures. The median survival for patients with DMPM is between four and 12 months, depending on the stage at presentation.

BACKGROUND*: Diffuse malignant pleural mesotheliomas (DMPMs) are highly lethal tumors that are becoming more common. Standard management approaches have provided limited effectiveness.

METHODS*: The literature on management has been revised, and the authors present their data on outcomes for 120 patients treated with an aggressive trimodality approach.

RESULTS*: An aggressive trimodality approach including extrapleural pneumonectomy followed by chemoradiation produces low mortality and acceptable morbidity. The five-year survival rate in patients with epithelial histology and negative nodes approaches 40%.

CONCLUSIONS: Mesothelioma is increasing in frequency and presents many diagnostic and management challenges. An optimal universal staging system is still awaiting definition and validation. Prognosis is best for patients with localized disease and epithelial histology. Surgical techniques including pleurectomy/decortication and EPP can result in a major debulking of disease, and studies are ongoing to determine if the addition of chemotherapy and radiation has an impact on survival. Several new investigational approaches are now being tested, including intrapleural interferon gamma, photodynamic therapy, immunotherapy, and gene therapy.