Malignant Sarcomatoid Mesothelioma
Understanding the Types of Malignant Mesothelioma Cancer
Malignant mesothelioma occurs when cancer cells grow in the pleura, which is a thin tissue that covers the lungs and lines the chest cavity. Malignant mesothelioma can also be found in the peritoneum, which lines the abdomen and covers most of its organs.
Risk factors include:
- Working or living in a place where asbestos is inhaled or swallowed
- Living with someone who works near asbestos
- While inconclusive, it seems that being exposed to the SV40 virus is a significant risk factor
Most people exposed to asbestos do not experience symptoms of mesothelioma until 20 to 50 years later. Malignant mesothelioma symptoms include lumps in the abdomen, weight loss, difficulty breathing, pain or swelling in the abdomen and pain under the rib cage.
Men are more likely than women to be diagnosed with malignant mesothelioma. Mesothelioma is diagnosed through a physical exam, complete blood count, chest x-ray, sedimentation rate, cytologic exam, bronchoscopy, or biopsy such as a thoracotomy, thoracoscopy, laparotomy or fine needle aspiration biopsy.
Malignant mesothelioma is divided into three types including sarcomatoid mesothelioma, biphasic mesothelioma, and epithelioid mesothelioma. Malignant mesothelioma types are then divided into subtypes under each type.
The nucleus of sarcomatoid cells is more difficult to detect under an electron microscope than the nuclei of epitheliold mesothelioma cells. Sarcomatoid mesothelioma cells can also divide into several other types of cancerous cells called tubopapillary cell, acinar cell, clear cell and small cell.
Malignant sarcomatoid mesothelioma usually stems from support tissues such as muscle, fat, bone and cartilage. It is often confused with high-grade sarcoma, sarcoma, sarcomatoid carcinoma and pulmonary sarcomatoid carcinoma because of the cell's irregular oval shape.
Approximately 10% to 15% of mesothelioma patients have malignant sarcomatoid mesothelioma, making it the least common type. However, this form of mesothelioma is the deadliest.
Sarcomatoid mesothelioma receives the same treatment as other forms of mesothelioma, but it is the most resistant to treatment. In addition to traditional mesothelioma treatment, new treatments include immunotherapy, gene therapy, intensity modulated radiation therapy, new chemotherapy agents and photodynamic therapy.

