Uveal Melanoma Associated With Myotonic Dystrophy: A Report of 6 Cases

Question  Is uveal melanoma associated with myotonic dystrophy?

Findings  In this case series, 6 patients were found to have myotonic dystrophy–associated uveal melanoma, including a case of myotonic dystrophy–associated iris melanoma and myotonic dystrophy–associated uveal melanoma in relatives. With variable follow-up of 6, 6, 41, 42, and 87 months (5 patients), findings included melanoma regression (4 of 5 tumors), melanoma recurrence (1 of 5 tumors), and no metastatic disease (5 of 5 patients); 1 patient declined treatment or follow-up.

Meaning  These findings suggest an association of myotonic dystrophy and uveal melanoma; patients with myotonic dystrophy may benefit from periodic ophthalmic examination.

Importance  Patients with myotonic dystrophy (MD) have an increased risk of malignancy including uveal melanoma. This case series further explores the association between these 2 diseases.

Objective  To describe a cohort of patients with uveal melanoma associated with MD, including a case of iris melanoma, and MD-associated uveal melanoma in relatives.

Design, Setting, and Participants  Retrospective case series at 3 tertiary referral centers (Wills Eye Hospital, Philadelphia, Pennsylvania; Mayo Clinic, Rochester, Minnesota; and Moorfields Eye Hospital, London, England), between January 1, 2000, and August 31, 2017. The study included 6 patients with MD and uveal melanoma.

Main Outcomes and Measures  Melanoma response to treatment and development of metastatic disease.

Results  There were 6 patients, 4 men and 2 women, with MD and uveal melanoma. The mean patient age at melanoma diagnosis was 47 years (median, 43 years; range, 30-67 years), and the tumor involved the choroid in 5 patients (83%) and iris in 1 patient (17%). The diagnosis of MD was known since young adulthood in 2 patients (33%) and was discovered in adulthood in 4 patients (67%). The main clinical features of MD included muscle weakness (n = 5; 83%), myotonia (n = 4; 67%), polychromatic cataract (n = 4; 67%), complications with general anesthesia (n = 4; 67%), myalgia (n = 3; 50%), cardiac arrhythmia (n = 2; 33%), and frontal baldness (n = 2; 33%). Genetic testing revealed MD type 1 (4 of 4 tested patients), and 2 patients demonstrated positive family history of MD with classic clinical features and preferred no testing. Melanoma treatment included plaque radiotherapy (n = 4; 67%), photodynamic therapy (n = 1; 17%), and declined treatment (n = 1; 17%). At follow-up of 6, 6, 41, 42, and 87 months (5 patients), findings included melanoma regression (4 of 5 tumors), melanoma recurrence (1 of 5 tumors), and no metastatic disease (5 of 5 patients).

Conclusions and Relevance  Six adult patients with MD demonstrated uveal melanoma involving the choroid or iris, emphasizing the association between these 2 diseases. Further research seems warranted to explore the pathogenesis of uveal melanoma in MD. These findings support the consideration of ophthalmic examination for uveal melanoma in patients with MD.