Risk factors of neoplastic disease in patients with systemic rheumatic disorders

Systemic inflammatory rheumatic disorders are associated with an increased risk of malignancy. The mechanism linking malignancy and rheumatic diseases is complex and multidirectional, and is only partially understood. This review focused on the incidence of neoplastic diseases in patients with the most common systemic rheumatic disorders. Rheumatoid arthritis is associated with a risk of malignancy that is about 10% higher than in the general population, and this is more related to the disease itself than to medication. Systemic lupus erythematosus is associated with an increased risk of neoplasms, particularly haematological malignancies such as non-Hodgkin lymphoma. The risk increases with long-lasting active disease. Systemic sclerosis is associated with an increased risk of lung and liver cancer, as well as malignancies of the haematological system. Men and patients with RNA polymerase III antibodies are at a higher risk. Dermatomyositis and polymyositis are subgroups of idiopathic inflammatory myopathy associated with a high risk of malignancy. Male gender and old age are additional risk factors. Other rheumatic diseases are also thought to be associated with an increased risk of cancer. Currently, the data are insufficient for a clear distinction to be made between subgroups at risk. Most patients with systemic autoimmune disorders are at enhanced risk of malignancy to some degree. The management of these patients should include procedures for the early detection of age- and population-specific malignancies, as well as those which are more prevalent in the patient population suffering from the individual rheumatic disease. It is important to note that an atypical disease course or increased treatment resistance for a rheumatic disorder may indicate that the observed changes are an expression of a paraneoplastic syndrome or that a new neoplasm is modifying the clinical course of an already diagnosed rheumatic disease.