Malignancy in patients with inflammatory myopathy

Abstract

The most recent evidence from population-based cohort studies confirms the association between malignancy and dermatomyositis and polymyositis. These studies show an even stronger association between polymyositis and malignancy than previous studies, suggesting less misclassification. This is particularly true of one study that used pathologic criteria to distinguish between myositis subtypes. Recent data also confirm that the association for dermatomyositis and polymyositis is not purely caused by diagnostic suspicion or surveillance bias. More data are still required to determine individual cancer risks, although it appears that ovarian and lung cancer are associated with dermatomyositis while lung cancer and non-Hodgkin's lymphoma are associated with polymyositis. An association between malignant disease and inclusion body myositis has also been verified for the first time. Of interest, too, is the increasing number of reports documenting cases in which the clinical course of the myositis mirrors that of the cancer, supporting the notion that in some instances, myositis is a paraneoplastic disorder.

Self-resolution of Epstein-Barr virus–associated B-cell lymphoma in a patient with dermatomyositis following withdrawal of mycophenolate mofetil and methotrexate

“…Patients with DM have an inherent increased risk of malignancy, mostly solid tumors, (eg, ovarian, gastrointestinal, and pulmonary) that are usually discovered within the first 3 years following diagnosis. [8][9][10][11][12]14,[30][31][32][33][34] In multiple population-based studies of rheumatic diseases including DM and rheumatoid arthritis, an increased risk for B-cell lymphoma of the CNS has not been demonstrated. [8][9][10][11][12][30][31][32]34 In contrast, a number of malignancies associated with immunosuppressive therapy are lymphoma or leukemia and are similar to those observed in other immunosuppressed states, such as AIDS and organ donor recipients on immunosuppressive therapies in whom extra-nodal large B-cell lymphomas predominate and tend to contain EBV.…”

“…Dermatomyositis (DM) is associated with cancer, especially ovarian cancer in women. [8][9][10][11][12] Although malignancy can develop after the diagnosis of dermatomyositis, there is little evidence that the use of immunosuppressive therapy to treat this condition is associated with the development of subsequent neoplasia. 4,6,[12][13][14][15][16][17][18][19] We present a patient with DM treated with immunosuppressive therapy for 5 years who developed an EBV-associated B-cell lymphoma of the CNS.…”

Idiopathic Inflammatory Myopathies and Malignancy: a Comprehensive Review

“…Additionally, the Bohan and Peter criteria, which do not take into account histological differences between PM, DM, and IBM, may have limitations in their specificity to properly diagnose and classify the different forms of IIM [21,22]. Cohort studies performed in Australia by Buchbinder et al [23,24], and more recently by Limaye et al [13], have attempted to correct for this by defining myositis subtypes based on well-recognized modern muscle biopsy criteria.…”

“…In 2002, a population-based cohort study based in Australia [23,24] confirmed an increased risk for malignancy in 537 patients with DM, PM, and IBM, with SIRs of 6.2, 2.0, and 1.8, respectively. One advantage of this study was that the population was identified based on muscle biopsy features.…”

Malignancy in Myositis

“…The association of dermatomyositis (DM) with malignancy was first reported in 1916 but only confirmed with more recent large, population-based, retrospective cohort studies [1,2]. Patients with polymyositis (PM) may also have an associated malignancy, but the risk is lower than that for DM patients.…”