TRIM33 and acquired idiopathic inflammatory myopathy: Anti-transcriptional intermediary factor 1γ (TIF1γ) autoantibodies are associated with malignancy in adult-onset idiopathic inflammatory myopathy (IIM) and this risk is attenuated if patients are also positive for anti-specificity protein 4 (Sp4) or anti-cell division cycle apoptosis regulator protein 1 (CCAR1).