Dermatomyositis (DM) is an uncommon inflammatory myopathy with characteristic rash accompanying, or more often preceding, muscle weakness. There is a well-recognized association between DM and several cancers, such as ovarian cancer, breast cancer, melanoma, colon cancer, and non-Hodgkin lymphoma. We report the first case of cancer of unknown primary site associated with DM. A 62-yr-old woman presented to us with both shoulder painful swelling and facial edema. She was diagnosed previously as cancer of unknown primary site, histologically confirmed with squamous cell carcinoma in a pelvic mass. For the following days, she complained of erythematous face followed by progressive weakness of the proximal muscles of upper and lower limbs. The laboratory tests showed an increased muscle enzyme and acute phase reactants. The electromyogram showed the typical findings of DM. After the treatment with high dose steroid and methotrexate, the proximal motor weakness improved, and she received palliative radiation therapy.
Carcinoma, Squamous Cell/complications/diagnosis/pathology ; Dermatomyositis/*complications/diagnosis/pathology/therapy ; Female ; Humans ; Middle Aged ; Neoplasms, Unknown Primary/*complications/diagnosis/pathology

Anti-Infective Agents ; administration & dosage ; therapeutic use ; Biomarkers ; blood ; Child, Preschool ; Dermatomyositis ; complications ; diagnosis ; therapy ; Edema ; etiology ; therapy ; Electromyography ; Extremities ; pathology ; physiopathology ; Hormones ; administration & dosage ; therapeutic use ; Humans ; Male ; Muscle, Skeletal ; pathology ; physiopathology ; Respiratory Tract Infections ; etiology ; therapy ; Tomography, X-Ray Computed

OBJECTIVETo explore the clinical and laboratory features and the prognosis of juvenile dermatomyositis (JDM) complicated with interstitial lung disease (ILD).

METHODData of 39 cases of JDM complicated with ILD hospitalized in Beijing Children's Hospital from January 2005 to December 2011 were collected. The clinical features, laboratory data and prognosis of these children were analyzed.

RESULTOf the 39 cases studied, 16 were boys, and 23 girls. The average age of onset was 5.6 years, and 61.5% of the patients' age of onset (24 cases) was under 6 years. Rashes (17 cases, 43.6%), simultaneous eruption of rashes and muscle weakness (14 cases, 35.9%), fever (4 cases, 10.1%), or muscle weakness (3 cases, 7.7%) were common initial symptoms of the disease. Only 51.3% of the patients (20 cases) had the symptoms of respiratory system, but (24 cases) 61.5% were complicated with that of the gastrointestinal system; (27 cases) 69.2% had at the same time electrocardiographic and echocardiographic abnormalities. The chest high resolution computed tomography (HRCT) showed cord or band-like shadows in their lungs of more than half of the cases (25 cases, 64.1%), and other changes included ground glass-like shadow (10 cases, 25.6%), net and lineation-like shadow (9 cases, 23.1%), nodular change (5 cases, 12.8%). The patients complicated with lung essential infiltration accounted for as high as 71.8% (28 cases). These imaging changes were largely seen on both dorsal sides of their lungs. Severe patients also had mediastinal emphysema, pneumothorax, pneumorrhagia or aerodermectasia. Twenty-four patients underwent pulmonary function examination, and 62.5% of the patients' pulmonary function (15 cases) was abnormal. The fatality rate of the cases studied was 10.1%.

CONCLUSIONThe imaging changes of patients suffering from JDM with ILD were often more severe as compared to the clinical symptoms, and were often complicated with damages to other systems and organs. The prognosis of those patients was poorer than others. Patients with JDM especially at a younger age of onset and with various organ damages should be examined with chest HRCT examinations as early as possible.

Child ; Child, Preschool ; Dermatomyositis ; complications ; diagnosis ; drug therapy ; Female ; Glucocorticoids ; administration & dosage ; therapeutic use ; Humans ; Immunosuppressive Agents ; administration & dosage ; therapeutic use ; Lung ; diagnostic imaging ; pathology ; Lung Diseases, Interstitial ; diagnosis ; drug therapy ; etiology ; Male ; Methotrexate ; administration & dosage ; therapeutic use ; Muscle Weakness ; diagnosis ; epidemiology ; etiology ; Prognosis ; Respiratory Function Tests ; Retrospective Studies ; Tomography, X-Ray Computed