Cancer phenotype in myotonic dystrophy patients: Results from a meta‐analysis

ABSTRACT Introduction: Recent studies have provided evidence that patients with myotonic dystrophy (DM) are at excess risk of cancer. However, inconsistencies regarding affected anatomic sites persist. Methods: We performed a meta‐analysis of cancer risk in DM, searching among studies published between January 1, 1990 and December 31, 2016. Eligible studies were full reports of DM cohorts with site‐specific risks. Results: The analysis included 5 studies, comprising 2,779 patients. Risk estimates for cancers of the endometrium and cutaneous melanoma were reported in all studies. The pooled standardized incidence ratio (pSIRs) for endometrial cancer was 7.48 (95% confidence interval [CI] 4.72–11.8) and for cutaneous melanoma was 2.45 (95% CI 1.31–4.58). Among cancers reported in 4 of 5 studies, elevated risks were observed for thyroid (pSIR = 8.52, 95% CI 3.62–20.1), ovarian (pSIR = 5.56, 95% CI 2.99–10.3), testicular (pSIR = 5.95, 95% CI 2.34–15.1), and colorectal (pSIR = 2.2, 95% CI 1.39–3.49) cancers. Discussion: Our data refine the DM cancer phenotype, which may guide patient clinical management and inform plans for molecular investigations to understand DM‐related carcinogenesis. Muscle Nerve 58: 517–522, 2018