Paraneoplastic dermatomyositis revealing undifferentiated nasopharyngeal carcinoma at early stage: a case report

Abstract

Context Dermatomyositis is a rare autoimmune disease characterized by noninfectious inflammatory damage of skin and predominant muscles in the belts. It is believed to be associated with about 1 in 1000 cases of nasopharyngeal carcinoma. This association has been described for locally advanced stages II and III nasopharyngeal carcinoma. It has rarely been described in the early stages (stage I). Case presentation A 65-year-old Moroccan patient residing in Casablanca, with no particular history was referred to the Mohamed VI Center for the treatment of cancers of the University Hospital Center IBN ROCHD in Casablanca, for treatment of nasopharyngeal cancer. He was admitted in poor general condition, performance status 3, with erythema on the face, neck, and extremities. The diagnosis of paraneoplastic dermatomyositis was made owing to progressive muscle weakness and elevation of muscle enzymes associated with the typical rash of the face and hands. He received corticosteroid therapy and then radiotherapy to the nasopharynx with good clinical outcome, disappearance of skin lesions, and recovery of muscle strength. Conclusions We report this case of dermatomyositis in early-stage nasopharyngeal carcinoma, which is a rarely described entity. Rapid treatment of dermatomyositis improved the patient’s quality of life and enabled him to support specific cancer treatments. This can be used as an element of early diagnosis and monitoring after treatment.