RESUMO
BACKGROUND: Necrotizing autoimmune myopathy is characterized by skeletal muscle weakness and is frequently associated with cancer. Absence of treatment can lead to severe muscular atrophy but initial symptoms may be insidious and delay the diagnosis. Here, we describe the case of a 70-year-old woman who was diagnosed with mnti-3-hydroxy-3-methylglutaryl-coenzyme A reductase myopathy during chemotherapy course for cervical cancer. CASE REPORT: A 70-year-old woman received chemotherapy for an advanced cervical carcinoma. She had no other relevant medical history and did not take statins. During the treatment she presented muscle weakness and myalgia. Biological tests showed elevated creatine phosphokinase level (3750 IU/l) and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase antibodies were detected in the serum. The electroneuromyogram showed short myotonic bursts in the upper limbs, with a myogenic appearance. A muscle biopsy was performed and confirmed the diagnosis of necrotizing autoimmune myopathy. The patient showed improvements after treatment with intravenous immunoglobulin and corticosteroid therapy. Then, the patient was successfully treated with subcutaneous methotrexate, which controlled the disease and demonstrated its value as maintenance treatment. CONCLUSION: This case highlights the importance of screening for rare myopathies in patients suffering from cancer with myalgias and muscle weakness and the importance of electroneuromyogram and magnetic resonance imaging in the early onset of symptoms to make the correct diagnosis.