Deposition of asbestos fibers in the parenchyma of the lung may result in the penetration of the visceral pleura from where the fiber can then be carried to the pleural surface, thus leading to the development of malignant mesothelial plaques. The processes leading to the development of peritoneal mesothelioma remain unresolved, although it has been proposed that asbestos fibers from the lung are transported to the abdomen and associated organs via the lymphatic system. Additionally, asbestos fibers may be deposited in the gut after ingestion of sputum contaminated with asbestos fibers.Pleural contamination with asbestos or other mineral fibers has been shown to cause cancer. Long thin asbestos fibers (blue asbestos, amphibole fibers) are more potent carcinogens than "feathery fibers" (chrysotile or white asbestos fibers). However, there is now evidence that smaller particles may be more dangerous than the larger fibers. They remain suspended in the air where they can be inhaled, and may penetrate more easily and deeper into the lungs. "We probably will find out a lot more about the health aspects of asbestos from [the World Trade Center attack], unfortunately," said Dr. Alan Fein, chief of pulmonary and critical-care medicine at North Shore-Long Island Jewish Health System.Mesothelioma development in rats has been demonstrated following intra-pleural inoculation of phosphorylated chrysotile fibers. It has been suggested that in humans, transport of fibers to the pleura is critical to the pathogenesis of mesothelioma.
Epidemiology
No circumstances are certain as to which an individual will get polymyalgia rheumatica, but a few factors show a relationship with the disorder:

Usually, PMR only affects adults over the age of 50. The average age of a person who has PMR is about 70 years old. Women are twice as likely to get PMR as men. Caucasians are more likely to get this disease. It is more likely to affect people of Northern European origin; Scandinavians are especially vulnerable. About 50% of people with temporal arteritis also have polymyalgia rheumatica. See also
Remitting seronegative symmetrical synovitis with pitting edema
Tocilizumab

References
External links
Questions and Answers about Polymyalgia Rheumatica and Giant Cell Arteritis - US National Institute of Arthritis and Musculoskeletal and Skin Diseases