[Adult onset Still's disease associated esophageal cancer: a case report].

We report a case of adult onset Still's disease in a 77 year old man, who was diagnosed as a esophageal cancer 9 months after the onset of this disease. At first malignant lesions in any organs were not found and steroid (prednisolone) therapy was begun and the patient was recovered from manifestations. But while tapering prednisolone to 15 mg, fever, arthritis and rash were observed again. Repeated examination revealed that he had suffered from esophageal cancer. This case is considered as a paraneoplastic syndrome of the esophageal cancer. Patients with adult onset Still's disease should be followed as a paraneoplastic syndrome.