Successful Treatment for Anti-melanoma Differentiation-associated Protein 5 Antibody-positive Dermatomyositis/Interstitial Lung Disease Associated with Lung Adenocarcinoma

Abstract

We encountered a rare case of early-stage lung adenocarcinoma and dermatomyositis with anti-melanoma differentiation-associated protein 5 antibody (MDA5-DM). The patient was a 57-year-old man with rapidly progressive interstitial lung disease (RP-ILD). Based on prognosis predicted by detailed evaluation of the patient's MDA5-DM/RP-ILD and lung adenocarcinoma, combined immunosuppressive therapy was started before surgical treatment of his lung adenocarcinoma. After 9 months of immunosuppressive therapy, the patient underwent radical thoracoscopic lobectomy. Cancer-associated dermatomyositis, especially MDA5-DM, should be prioritized for treatment based on the prognostic prediction for each disease.