Successful resection of dermatomyositis associated with thymic carcinoma: report of a case.

We report a case of thymic carcinoma associated with dermatomyositis (DM) in a 53-year-old man. The patient presented with the characteristic features of a skin rash with Gottron's papules, proximal muscle weakness, and increased serum levels of the muscle-associated enzymes. Comprehensive clinical examinations revealed an anterior mediastinal tumor. We resected the tumor and histological examination confirmed squamous cell carcinoma of the thymus. Thereafter, his clinical symptoms improved dramatically and his serum levels of muscle-associated enzymes dropped, indicating that the DM was a paraneoplastic phenomenon. Our search of the literature found only one other case report of DM accompanied by thymic carcinoma, and to our knowledge, this is the fi rst documented case of dramatic improvement of DM after resection of thymic carcinoma. We propose that thymic carcinoma should be added to the list of malignancies that can complicate DM as a paraneoplastic disease.