Myotonic Muscular Dystrophy Tied to Increased Cancer Risk
Significantly increased risk seen for cancers of the brain, endometrium, ovary, and colon
TUESDAY, Dec. 13 (HealthDay News) -- Patients diagnosed with myotonic muscular dystrophy (MMD) are at an increased risk of developing cancer, according to a study published in the Dec. 14 issue of the Journal of the American Medical Association.
Shahinaz M. Gadalla, M.D., Ph.D., from the National Institutes of Health in Bethesda, Md., and colleagues investigated the risk of cancer among 1,658 patients with an MMD diagnosis in Swedish and Danish Registers between 1977 and 2008. The risk of all cancers combined and by anatomic site, stratified by age and gender, were determined for all patients followed up from their first MMD-related inpatient or outpatient contact to first cancer diagnosis, death, emigration, or completion of cancer registration.
The investigators found that 104 patients with a discharge diagnosis of MMD developed cancer during follow-up, which yielded an observed cancer rate of 73.4 per 10,000 person-years in MMD, compared to an expected rate of 36.9 per 10,000 person-years in the general population (standardized incidence ratio [SIR], 2.0). Significantly increased risks of cancer were seen in the endometrium (SIR, 7.6), brain (SIR, 5.3), ovary (SIR, 5.2), and colon (SIR, 2.9). Women and men had similar cancer risks after excluding genital organ tumors (SIR, 1.9 and 1.8, respectively). The pattern of cancer excess was similar in the Swedish and Danish cohorts.
"Patients with MMD identified from the Swedish and Danish patient registries were at increased risk of cancer both overall and for selected anatomic sites," the authors write.