Sarcomatoid mesothelioma is the least common histological type of mesothelioma, but it is the most aggressive.
Even more than epithelial mesothelioma, the sarcomatoid form is difficult to diagnose and to distinguish from other diseases. Just looking at the cells under a microscope is not enough, and doctors employ immunohistological tests to distinguish Sarcomatoid mesothelioma from true sarcoma and pulmonary sarcomatoid carcinoma.
The general treatment plan for sarcomatoid mesothelioma focuses on:
- Managing pleural effusions
- Administering radiotherapy to intervention sites
- Evaluating suitability for radical surgery
- Evaluating suitability for chemotherapy and clinical trial entry
Managing pleural effusions
A pleural tap – formally called thoracocentesis – can help manage malignant pleural effusions. The doctor puts a hole in the body and drains fluid. Timely and effective management of pleural effusions helps symptom palliation and reduces the risk of a trapped lung.
For patients that qualify for surgery (as determined by age and overall health), thoracoscopy – insertion of an instrument to allow visual inspection of the chest cavity - can be useful. This procedure allows doctors to see the pleural surface, carry out histological sampling for diagnosis and completely drain out accumulated pleural fluid followed by pleurodesis through talc poudrage. Pleurodesis is when the doctor tries to eliminate the pleural space as a potential point of accumulation of fluid. Sterile talc is the ideal sclerosing agent.
When patients have a trapped lung, or when pleurodesis fails to deliver results, a pleuro-peritoneal shunt can be used.
Radiotherapy for sarcomatoid mesothelioma
Doctors sometimes use radiotherapy to slow local tumor growth. There have been cases where radiotherapy has resulted in regression of disease. Radiotherapy reduces pain in around 50% of patients. Unfortunately, radiotherapy is rarely useful when it comes to palliation of dyspnea or managing mediastinal infiltration symptoms.
Sarcomatoid mesothelioma can spread to distant areas in the body and if doctors use radiation over a large area it might damage organs that have not been affected by the cancer. Despite efforts, no substantial benefit from radical radiotherapy has been found in mesothelioma cases.
Targeted radiotherapy is sometimes used on mesothelioma because the tumor is spread out and irregular. Referred to as intensity modulated radiotherapy (IMRT), this treatment can help improve local tumor control while reducing risk of exposure to neighboring organs.
Mesothelioma might affect (seed) malignant cells when surgery is carried out. Administering radiotherapy to areas where the surgery happens can help prevent this complication.
Surgery for sarcomatoid mesothelioma
Surgical procedures include debulking surgery (also called cytoreductive surgery or pleurectomy/decortication (P/D)), surgical pleurodesis using video assisted thoracoscopic surgery (VATS) and extra pleural pneumonectomy (EPP).
EPP is often used in a trimodality treatment approach involving surgery, chemotherapy and radiotherapy.