Since myofascial edema of the gastrocnemius was found in all our tested patients and a high frequency of gastrocnemius myofascial edema was not reported in any other group of IIMs, we assumed that this unique MRI finding could be helpful in the early diagnosis of anti‐TIF1‐γ antibody‐positive DM to monitoring malignancy occurrence. The gene discussed is TRIM33; the disease is dermatomyositis.