Predicting factors of malignancy in dermatomyositis and polymyositis: a case-control study

Abstract

The two independent predictive factors for malignancy (P < 0.05) in patients with DM/PM were an older age at onset (> 45 years) and male gender. The primary idiopathic DM group was shown to have higher risk of developing internal malignancies, especially NPC. However, this was not identified as an independent predictive factor for concomitant neoplastic diseases in multivariate analysis. In addition, patients who had the complication of interstitial lung disease had a significantly lower frequency of malignancies (P < 0.001).