438 The Journal of Rheumatology 2008; 35:3 Personal non-commercial use only. The Journal of Rheumatology Copyright © 2008. All rights reserved. Dermatomyositis and Polymyositis Associated with Malignancy: A 21-year Retrospective Study CSILLAANDRÁS,ANDREA PONYI, TAMÁS CONSTANTIN, ZOLTÁN CSIKI, ÉVA SZEKANECZ, PETER SZODORAY, and KATALIN DANKÓ ABSTRACT. Objective. To analyze clinical and laboratory data of patients diagnosed with dermato- or polymyositis between 1985 and 2006, retrospectively, with particular emphasis on association with malignant diseases. Methods. A thorough clinical assessment was performed on the immunological features and therapeu- tic responses, as well as survival data. In the case of 155 myositis patients, HLA haplotypes were also investigated. Results. Out of 309 patients with myositis in our database, malignant disease was found in 37 cases. Thirty patients had dermatomyositis (28.8%), and 7 had polymyositis. In 64.8% of the cases, the malig- nancy and myositis appeared within 1 year. The highest probability for tumor recognition was before 2 years and after 3 years of the diagnosis of myositis (28 cancer-associated myositis): most frequent was breast tumor, and adenocarcinoma was the predominant histological type. The skin lesions and diaphragmatic involvement were more severe; distal muscle weakness was conventional, along with proximal muscle weakness and frequent immobility. Creatine kinase and lactate dehydrogenase eleva- tions were lower than in primary myositis, and when controlled 1 month after surgical treatment of the malignant disease, these values showed significant reduction. Tumor markers did not predict the occult tumors. We found no correlation between the presence of tumor and DRB1-0301 and -01 alleles. Conclusion. In patients with tumor-associated myositis, it was more frequently necessary to administer other immunosuppressive drugs along with glucocorticoids. The successful treatment of the underlying malignant disease improved the clinical course of myositis. The overall survival rate was considerably worse when compared to other forms of myositis. (First Release Jan 15 2008; J Rheumatol 2008;35:438–44) Key Indexing Terms: DERMATOMYOSITIS POLYMYOSITIS MALIGNANCY From the Department of Oncology and Division of Clinical Immunology, 3rd Department of Internal Medicine, University of Debrecen, Medical and Health Science Center, Debrecen; and the 2nd Department of Pediatrics, Semmelweis University, Faculty of Medicine, Budapest, Hungary. Supported by the Hungarian Research Foundation (OTKA) T 046931 and ETT 1F1KC0004320. C. András, MD; É. Szekanecz, MD, Department of Oncology; Z. Csiki, MD, PhD; P. Szodoray, MD, PhD; K. Dankó, PhD, DSci, Division of Clinical Immunology, 3rd Department of Internal Medicine, University of Debrecen, Medical and Health Science Center; A. Ponyi, MD, PhD; T. Constantin, MD, 2nd Department of Pediatrics, Semmelweis University, Faculty of Medicine. Address reprint requests to Dr. K. Dankó, Division of Clinical Immunology, 3rd Department of Internal Medicine, Medical and Health Science Center, University of Debrecen, Móricz Zs. 22, H-4004 Debrecen, Hungary. E-mail: danko@iiibel.dote.hu Accepted for publication October 15, 2007. Dermatomyositis (DM) and polymyositis (PM) belong to the group of idiopathic inflammatory myopathies (IIM). These are systemic autoimmune diseases characterized by progres- sive, symmetrical weakness of the proximal muscles and in the case of DM, by cutaneous lesions. Researchers and clini- cians have been interested for decades in the association of malignant diseases with IIM, mainly with DM. In 1916, Stertz was the first to describe a patient with biopsy-proven DM and stomach adenocarcinoma 1 . Later, several studies examined the relationship between DM/PM and malignant diseases, and an increased incidence of malignancy in myositis patients, particularly in DM, was reported in most studies 2,3 . In addi- tion to DM/PM, other types of IIM may be associated with malignancy: juvenile DM, amyopathic DM, and inclusion body myositis 4-6 . The following reasons have been considered probable for the association of myositis and malignant diseases 7 : (1) para- neoplastic syndromes — bioactive mediators produced by the tumor induce immune reactions against muscle fibers and skin; (2) causal role of the compromised immune system in the outbreak of tumor and myositis 8 ; (3) malignant transfor- mation induced by the second-line cytotoxic agents used in the treatment of myositis; (4) common carcinogenic environ- mental factors that can trigger immune reaction at the same time; and (5) immune reactions against the tumor, which transforms into an autoimmune syndrome as a consequence of the cross-reactivity with skin and muscle antigens 9 . Some observations suggest a model of paraneoplasia focusing on common autoantigen expression and immune targeting between cancer tissues and muscle tissue in myositis 10 . We assessed the clinical and laboratory data of patients with DM/PM with particular emphasis on association with malignant diseases. www.jrheum.org Downloaded on January 21, 2023 from