Association of Cancer and Anti-Synthetase Syndrome: A Retrospective Multicenter Study

Area of Science:

• Rheumatology
• Oncology
• Internal Medicine

Background:

• Anti-synthetase syndrome is a rare autoimmune disease.
• Cancer-associated myositis (CAM) is a rare complication of autoimmune diseases.
• The incidence and prognostic impact of CAM in anti-synthetase syndrome are not well-established.

Purpose of the Study:

• To determine the incidence of CAM in patients with anti-synthetase syndrome.
• To identify factors associated with CAM in this population.
• To evaluate the impact of CAM on patient prognosis.

Main Methods:

• Retrospective multicenter study of adult patients with anti-synthetase syndrome.
• Multivariable logistic regression to identify cancer predictors.
• Unsupervised analysis for patient clustering.
• Cox proportional hazard models for mortality assessment.

Main Results:

• 11.4% of patients had CAM, with a standardized incidence ratio of 5.4 compared to the general population.
• Older age and a history of cancer were independently associated with CAM.
• CAM patients had worse overall survival and it was an independent predictor of death.
• CAM cluster showed older age, milder muscle involvement, and lower Jo-1 antibodies.

Conclusions:

• CAM is not rare in anti-synthetase syndrome and has a higher incidence than in the general population.
• CAM is associated with significantly worse prognosis and increased mortality.
• Cancer screening should be prioritized in older anti-synthetase syndrome patients with a history of cancer.