Dermatomyositis is an inflammatory myopathy involving the skin that typically affects patients between 40-60 years of age and is more likely to be diagnosed in women. Around 10-20% of dermatomyositis cases present with subclinical or absent muscle involvement, termed "clinically amyopathic." Presence of anti-transcription intermediary factor 1? (TIF1?) antibodies is an important indicator of underlying malignancy. We present a patient with anti-TIF1? positive amyopathic dermatomyositis associated with bilateral breast cancer. The patient was safely treated with trastuzumab for breast cancer and intravenous immunoglobulin for dermatomyositis
