Rapid changes of nailfold capillary abnormalities during treatment for a patient with dermatomyositis complicated by lung cancer: a case report.

Nailfold capillary abnormalities are typically observed in patients with systemic sclerosis and are also often found in patients with polymyositis (PM) and dermatomyositis (DM). Nailfold capillary abnormalities in some patients with PM/DM were found to improve with immunosuppressant treatment. However, the short-term changes in nailfold capillaries and their associations with disease activity have not been established yet. Additionally, there have been no reports on whether nailfold capillary abnormalities can change during the progression of malignant tumours. A man in his 60s with anti-transcriptional intermediate factor 1γ (anti-TIF-1γ) antibody-positive DM complicated with small cell lung carcinoma was treated with prednisolone (PSL) 70 mg, carboplatin (CBDCA) and etoposide (VP-16). His nailfold capillary abnormalities improved rapidly, and the tumour size decreased with treatment. Although chemotherapy was continued, abnormalities in the nailfold capillaries gradually recurred. The worsening of the capillary abnormalities prompted us to examine computed tomography scans, which showed the recurrence of lung cancer. After switching to second-line chemotherapy, the change in the nailfold capillary abnormalities was again in a parallel course with the disease status of lung cancer. Changes in nailfold capillaries may be useful not only for the diagnosis but also for the evaluation of the recurrence of malignant tumours with DM.