INCREASED RISK OF MELANOMA IN PARKINSON'S DISEASE 

SYDNEY, Australia — A new study suggests that patients with Parkinson's disease (PD) have about a 4-fold increased risk for development of malignant melanoma, underscoring the importance of dermatologic screening in PD, the researchers say.

Radu Constantinescu, MD, from the University of Rochester Medical Center in New York, presented the study here June 18 at the Movement Disorder Society (MDS) 17th International Congress of Parkinson's Disease and Movement Disorders.

Prior studies have shown that the overall risk for cancer in patients with PD is lower but the risk for malignant melanoma is higher compared with the general population. The latter was observed by Dr. Constantinescu and colleagues in the Deprenyl and Tocopherol Antioxidative Therapy of Parkinsonism (DATATOP) trial (Mov Disord. 2007;22:720-722).

In their latest study, they looked at the risk for malignant melanoma in 1741 patients with early, treated PD enrolled in the National Institutes of Health Exploratory Trials in PD Long-term Study-1 (NET-PD-LS-1).

During 6763 person-years of follow-up, there were 13 cases of malignant melanoma in the patients with PD compared with 3.79 cases expected in the general population.

The standard event ratio for malignant melanoma in the NET-PD-LS-1 population was 3.4 (95% confidence interval [CI], 1.8 - 5.9), the researchers say.

"Although more than 20 years have passed and the general awareness in regard to malignant melanoma in PD has increased, the risk observed in the NET-PD-LS-1 study is similar to the one seen in the DATATOP population," the authors say.

This study "documents an approximately 4-fold higher risk of developing melanoma in PD subjects, comparable to what was observed almost 20 years ago in the DATATOP trial," MDS president-elect Matthew Stern, MD, Parkinson's Disease and Movement Disorders Center, University of Pennsylvania, Philadelphia, who wasn't involved in the study, said in a conference statement.

Lisa Cannon-Albright, PhD, from the University of Utah in Salt Lake City, who reviewed the data for Medscape Medical News, said it "does look like yet another confirmation" of the association between melanoma and PD. "I don't see anything new here," she added.

As reported recently by Medscape Medical News, Dr. Cannon-Albright and colleagues uncovered a novel association between PD and prostate cancer and confirmed the association with melanoma in an analysis of the Utah Population Database.

Dr. Stern said the new study "underscores the importance for dermatologic screening in PD patients. Further, elucidating the relationship between PD and melanoma may shed light on the pathogenesis of both disorders," he added.

The authors, Dr. Stern, and Dr. Cannon-Albright have disclosed no relevant financial relationships.

Movement Disorder Society (MDS) 17th International Congress of Parkinson's Disease and Movement Disorders. Abstract 404. Presented June 18, 2013.