[A case report of a patient with overlap syndrome systemic lupus erythematosus( SLE) and polymyositis( PM)whose condition improved following treatment for coexisting descending colon cancer].

Here, we report a case of a patient with overlap syndrome (systemic lupus erythematosus[SLE]and polymyositis[PM]) whose condition improved following treatment for coexisting descending colon cancer. A 75-year-old man experienced Raynaud symptoms and arthralgia. He was diagnosed as having overlap syndrome (SLE/PM) and was treated with steroids. However, the symptoms did not improve. Descending colon cancer was diagnosed by colonoscopy. After surgery, overlap syndrome improved immediately. Overlap syndrome was considered as a paraneoplastic event caused by the coexisting descending colon cancer.