From the Guidelines
Mesothelioma affects the pleura by causing malignant tumors to develop in this thin membrane that lines the lungs and chest cavity, leading to inflammation, cellular damage, and eventual cancerous changes, as supported by the most recent guidelines 1.
Pathophysiology of Mesothelioma
When asbestos fibers are inhaled, they can become lodged in the pleural tissue, triggering a cascade of events that ultimately leads to the development of malignant tumors. The disease typically progresses through several stages, beginning with localized thickening of the pleural tissue and eventually forming nodular masses that can spread across the pleural surface. As the cancer advances, it causes the pleura to thicken and harden, restricting lung expansion.
Clinical Presentation and Diagnosis
Fluid often accumulates in the pleural space (pleural effusion), compressing the lung and causing symptoms like chest pain, shortness of breath, and persistent cough. The cancer can eventually invade nearby structures including the chest wall, diaphragm, and pericardium. This progressive invasion explains why patients experience worsening respiratory function and increasing pain as the disease advances, with symptoms typically appearing 20-50 years after asbestos exposure, as described in the European Respiratory Journal 1.
Management and Treatment
The management of malignant pleural mesothelioma involves a multimodal approach, including surgery, chemotherapy, and radiation therapy, as outlined in the guidelines by the European Respiratory Society and the European Society of Thoracic Surgeons 1. The use of palliative care is also crucial in managing symptoms and improving quality of life for patients with mesothelioma, with a focus on controlling pain, reducing excessive sweating, and addressing psychological burden, as highlighted in the Annals of Oncology 1.
- Key considerations in the management of mesothelioma include:
- Multimodal treatment approaches, including macroscopic complete resection, chemotherapy, and radiation therapy
- Palliative care, including pain control, management of excessive sweating, and addressing psychological burden
- Individualized treatment plans, taking into account the patient's overall health, disease stage, and tumor histology
- The importance of early diagnosis and treatment cannot be overstated, as it can significantly impact patient outcomes and quality of life, as emphasized in the American Journal of Respiratory and Critical Care Medicine 1.
From the Research
Mesothelioma and Pleura
- Mesothelioma is a primary and locally aggressive tumor of the pleura, with a well-defined causal relationship with asbestos exposure 2.
- The effects of mesothelioma on the pleura can include chest pain, dyspnea, and pleural effusion, with breathlessness due to a pleural effusion without chest pain reported in about 30% of patients 3.
- Malignant pleural mesothelioma (MPM) is the most common form of mesothelioma, and its incidence is increasing, with an expected peak in the next 10-20 years 3.
Symptoms and Diagnosis
- Typical presenting features of mesothelioma include chest pain and dyspnea, with a chest wall mass, weight loss, sweating, abdominal pain, and ascites (due to peritoneal involvement) being less common presentations 3.
- A combination of accurate exposure history, examination radiology, and pathology are essential to make the diagnosis, with distinguishing malignant from benign pleural disease being challenging 3.
- The most helpful CT findings suggesting malignant pleural disease include a circumferential pleural rind, nodular pleural thickening, pleural thickening of > 1 cm, and mediastinal pleural involvement 3.
Treatment Options
- The current therapeutic actions for MPM are limited due to the late stage at which most patients are diagnosed and the intrinsic chemo-resistance of the tumor, with the recommended systemic therapy being the cisplatin/pemetrexed regimen 2, 4, 5.
- Immunotherapeutic approaches, including immune-checkpoint inhibitors (ICIs), engineered T cells to express chimeric antigen receptors (CARs), and dendritic cells (DCs) vaccines, are being investigated as novel therapeutic approaches for MPM 6.
- A multimodal approach, including surgery, radiotherapy, and chemotherapy, is considered the cornerstone of treatment for MPM, with ongoing international and national trials addressing the roles of these treatments 2.