Germline genotyping identified a panel of deleterious germline mutations in immune regulation genes, including a variant in <i>CR2</i> (rs367567954), which encodes a receptor for EBV on B cells and may contribute to their aberrant activation.<h4>Conclusion</h4>This case illustrates that refractory anti-TIF1γ-DM can persist even after the associated malignancy is well controlled and underscore the need for long-term vigilance and personalized management strategies in paraneoplastic DM. This evidence concerns the gene TRIM33 and dermatomyositis.