A Case of Docetaxel Induced Myositis and Review of the Literature

In phase I and II trials taxane chemotherapeutic agents reported side effects, including myelosuppression, peripheral edema, and fluid retention. With further use of these agents, studies in the late 1980s and early 1990s began to report peripheral neuropathy and proximal muscle weakness as common complaints, the later with unexplained pathophysiology. We report a 65-year-old Hispanic woman with estrogen receptor (ER) and progesterone receptor (PR) positive invasive ductal breast carcinoma who presented with right thigh pain and swelling eight days after her third infusion of docetaxel (a taxane chemotherapeutic) and cyclophosphamide. Laboratory findings were notable for elevation in creatine phosphokinase (CPK), aldolase, and erythrocyte sedimentation rate (ESR); a magnetic resonance imaging (MRI) of her lower extremities showed evidence of bilateral muscle edema involving the anterior compartment muscles of the thighs. A workup to rule out other causes of myositis was negative. Docetaxel was not reintroduced and the patient improved with corticosteroids. Since 2005 this is, to our knowledge, the fifth reported case of docetaxel related inflammatory myositis. Taxanes have been noted to cause disabling but transient arthralgias and myalgias; it is important to consider the possibility of inflammatory myopathy as a possible complication in patients undergoing treatment with these agents.