Its leading cause is asbestos exposure, a mineral used in construction whose use was banned four decades ago.
The Mesothelioma is a tumor derived from the mesothelial cells of the pleura, peritoneum, pericardium, and tunica albuginea of the testis.
Pleural location is the most frequent (80%), affecting the pleura diffusely. The pleura is the membrane that covers the rib cage and the surface of the lungs.
It is a rare tumor. The incidence is highest in Australia, Belgium, and Great Britain (with more than 20 cases per million inhabitants); in Spain, the incidence is less than 22 cases per million. Mesothelioma represents 0.3% of cancer deaths. The incidence is higher in men than in women.
The median survival of those affected by malignant Mesothelioma is between 6 and 18 months.
Causes of Mesothelioma
Asbestos – the trade name for a mineral made up of silica, magnesium, lime, and ferrous oxide -, also known as asbestos, is the leading cause of Mesothelioma. Its carcinogenic capacity has been demonstrated in animals. In humans, it has been proven that the risk is proportional to the exposure to it, with miners and workers in the shipbuilding, construction, textile, and plumbers industries being the groups at most significant risk.
Currently, there are various court cases and victims’ associations claiming compensation for those affected by its use. The last, after the complaint of a Madrid Metro worker who has uncovered the presence of asbestos in several old trains still in circulation, and which has meant that the Labor Inspectorate of the Ministry of Employment has drawn up a record of infringement for non-compliance “very serious “of the safety regulations.
The latency period (time between exposure and the disease onset) can be between 14 and 75 years. Other factors that can influence are the exposure time, intensity, and environmental exposure. There are even cases of familial Mesothelioma.
Other causes of Mesothelioma are ionizing radiation (increased incidence in patients previously treated with radiotherapy) or the SV40 virus, present in between 60 and 86% of mesothelioma samples (although conclusive results cannot be extracted in studies).
The initial symptoms of Mesothelioma usually appear months before diagnosis in the form of chest pain (not pleuritic, such as a puncture, but dull and poorly located) and dyspnea (sensation of respiratory distress) variable about the amount of pleural effusion.
It occurs most of the time unilaterally (95%), especially in the right hemithorax area (60%), probably to its greater volume.
The progression of the disease produces respiratory failure. The invasion of neighboring structures can lead to dysphagia (difficulty swallowing), dysphonia, brachial plexopathy (involvement of the nerve plexus). Or superior vena cava syndrome (when there is compression of this main vein symptom such as dyspnea, facial and arm swelling, cough, chest pain, dysphagia, cyanosis, congestion, headache, and dizziness).
Mesothelioma can also be accompanied by symptoms derived from paraneoplastic syndromes. These are various groups of symptoms suffered by cancer patients, which cannot be explained by the local invasion of the tumor or its metastases but are associated with the release of biologically active substances on the part of the tumor their effects at a distance.