Purpose: Dermatomyositis (DM) represents an auto-immune inflammatory myopathy. In this review, we analyzed the incidence of DM as a clinical manifestation highlighting the peculiar clinical and treatment characteristics of this disease when occurring in the context of different malignancies.
Methods: A systematic literature review was performed based on database search in PubMed/Medline and included English articles until December 2016.
Results: In up to 20% of cases DM appears as a paraneoplastic syndrome associated with multiple malignancies such as ovarian, breast, prostate, lung, nasopharyngeal and colorectal cancer, and non-Hodgkin lymphomas. It can be presented either before, in the time, or after cancer diagnosis. Systemic sclerosis and mixed connective-tissue disease represent common coinciding disorders. Particular caution should be given in the radiotherapy because the microvascular endothelial radiation damage and autoimmune inflammatory collagen vascular disease caused by DM may be additive. There is a higher risk of late toxicity in the presence of other concurrent vascular diseases, including diabetes, hypertension or administration of chemotherapy. Prednisone represents the first-line treatment option but immunosuppressive drugs such as azathioprine and methotrexate may also be incorporated in the therapeutic armamentarium especially when DM is associated with malignancy. Intravenous immunoglobulin could be a promising alternative in prednisone-resistant cases. The effectiveness of therapies with antigen-specific agents such as monoclonal antibodies is currently under investigation.
Conclusions: Timely diagnosis coupled with a treatment plan focused on muscular endurance and improvement of skin lesions and other symptoms offer a favorable response to therapy along with the achievement of a higher quality of life for these patients.