Inflammatory myopathy(dermatomyositis and polymyositis): Issues with malignancy
Dermatomyositis and polymyositis are inflammatory myopathies with symptoms of proximal muscle weakness and muscle inflammation. Unlike PM, DM also includes multiple skin lesions. They are often accompanied by other rheumatic diseases.
First, the pathophysiology of inflammatory myopathy is not completely understood. However, there is a relationship between inflammatory myopathy and cancer in several patients. In myositis - persistent muscle tissue, a higher concentration of myositis - specific autoantibodies is secreted by other common muscle tissues. These autoantibodies are known to be present at high concentrations in various types of cancers that are known to be associated with myositis. These observations suggest that there are autoantibodies common to diseases such as PM, DM, and cancer, and antibodies targeting tumor tissues can also cause muscle damage.
The types of cancer that are associated with inflammatory myositis include ovarian cancer, cervical cancer, lung cancer, pancreatic cancer, bladder cancer, and stomach cancer account for about 70 percent of the cancers. Several studies have also shown that the risk of ovarian cancer increases somewhat. In some populations, cancer with an increased incidence associated with DM, PM is often a cancer of the population.
When looking at the temporal relationship between cancer and inflammatory myositis, cancer can be identified both before, during, and after diagnosis of inflammatory myositis. The most common cancer is found within one year after diagnosis of inflammatory myositis.
Several studies have shown a greater risk of cancer in DM than in PM. Other risk factors include capillary damage in muscle biopsy, skin necrosis, skin leukocytoclastic vasculitis, and aging and dysphagia. Patients with ILD are known to have a low risk of cancer.
The presence of cancer associated with inflammatory myositis does not change the severity of muscle weakness in PM or DM, the duration of muscle weakness before diagnosis, or the increase in blood coagulation. However, if cancer is accompanied by inflammatory myositis, the response to treatment is not as good as in the absence of cancer. Therefore, if inflammatory myositis is not responding well to treatment, the possibility of accompanying cancer should always be questioned.
First, the pathophysiology of inflammatory myopathy is not completely understood. However, there is a relationship between inflammatory myopathy and cancer in several patients. In myositis - persistent muscle tissue, a higher concentration of myositis - specific autoantibodies is secreted by other common muscle tissues. These autoantibodies are known to be present at high concentrations in various types of cancers that are known to be associated with myositis. These observations suggest that there are autoantibodies common to diseases such as PM, DM, and cancer, and antibodies targeting tumor tissues can also cause muscle damage.
The types of cancer that are associated with inflammatory myositis include ovarian cancer, cervical cancer, lung cancer, pancreatic cancer, bladder cancer, and stomach cancer account for about 70 percent of the cancers. Several studies have also shown that the risk of ovarian cancer increases somewhat. In some populations, cancer with an increased incidence associated with DM, PM is often a cancer of the population.
When looking at the temporal relationship between cancer and inflammatory myositis, cancer can be identified both before, during, and after diagnosis of inflammatory myositis. The most common cancer is found within one year after diagnosis of inflammatory myositis.
Several studies have shown a greater risk of cancer in DM than in PM. Other risk factors include capillary damage in muscle biopsy, skin necrosis, skin leukocytoclastic vasculitis, and aging and dysphagia. Patients with ILD are known to have a low risk of cancer.
The presence of cancer associated with inflammatory myositis does not change the severity of muscle weakness in PM or DM, the duration of muscle weakness before diagnosis, or the increase in blood coagulation. However, if cancer is accompanied by inflammatory myositis, the response to treatment is not as good as in the absence of cancer. Therefore, if inflammatory myositis is not responding well to treatment, the possibility of accompanying cancer should always be questioned.
