TOPLINE

Recent cancer screening guidelines in people with dermatomyositis were successfully validated in an external cohort by correctly placing those with the highest rate of paraneoplastic disease among those classified into a high-risk group (8.8%), followed by lower rates in those in intermediate- (5.1%) and low-risk groups (2.5%).

METHODOLOGY

• Researchers retrospectively reviewed records of 413 adult patients with dermatomyositis or clinically amyopathic dermatomyositis seen at Mount Sinai Health System clinics in the US from 2019 to 2024.
• Patients were included if they had two or more follow-up visits for their dermatomyositis diagnosis in dermatology or rheumatology clinics, with data collected on demographics, clinical findings, laboratory results, myositis-specific autoantibody (MSA) panels, and cancer screening or diagnosis.
• Patients were stratified into high-risk, intermediate-risk, and low-risk categories according to International Myositis Assessment and Clinical Studies Group guidelines based on the presence of various risk factors.
• Furthermore, patients with cancer diagnosed within 3 years before or after the onset of dermatomyositis were categorized as having paraneoplastic dermatomyositis; 6.5% of the patients received this diagnosis ( 88.9% women).

TAKEAWAY

• Among patients with paraneoplastic dermatomyositis, 70.4% were classified into the high-risk group, whereas among those with nonparaneoplastic dermatomyositis, 51% were classified into the high-risk group; the proportion of paraneoplastic disease was highest in the high-risk group at 8.8%, followed by 5.1% in the intermediate-risk group and 2.5% in the low-risk group.
• An age of 40 years or older at idiopathic inflammatory myopathy diagnosis was associated with increased odds of paraneoplastic dermatomyositis (odds ratio, 7.09; 95% CI, 1.72-62.7), whereas having two or more high-risk factors or individual MSA or myositis-associated autoantibodies was not significantly associated with paraneoplastic dermatomyositis.
• The most common malignancies among patients with paraneoplastic dermatomyositis were breast cancer (37%) and lung cancer (19%), with 33% of patients diagnosed with cancer before the onset of dermatomyositis (mean, 12.6 months earlier) and 67% diagnosed after dermatomyositis onset (mean, 23.1 months later).
• Among patients in the intermediate-risk group, 83% were diagnosed with paraneoplastic cancers more than a year after the diagnosis of dermatomyositis.

IN PRACTICE

“Our findings support the real-world clinical utility of the [International Myositis Assessment and Clinical Studies] guidelines for risk-based cancer screening in newly diagnosed [dermatomyositis] and suggest the indication for continued monitoring in intermediate-risk patients,” the authors wrote.

SOURCE

The study was led by Isabel Silva, Icahn School of Medicine at Mount Sinai in New York City. It was published online on July 1, 2026, as a brief report in ACR Open Rheumatology.

LIMITATIONS

The study was retrospective in nature and was carried out at a single center. The proportion of paraneoplastic cases was small. Patients with limited follow-up may have been excluded, as two or more visits were required. The different lengths of follow-up may have affected the ability to fully capture postdiagnosis malignancy within 3 years after a dermatomyositis diagnosis.

DISCLOSURES

The study did not report any specific funding. One author disclosed receiving research funds and serving as a consultant for various pharmaceutical companies, including Leo Pharma, AbbVie, and others.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.