Risk Factors for Developing a Second Melanoma Identified

In patients with cutaneous melanoma, red and blond hair, having more than 50 cherry angiomas and more than 100 common melanocytic nevi significantly increased the risk for developing a second melanoma, according to data published in the Journal of The European Academy of Dermatology and Venereology.

Researchers conducted a longitudinal case-case study of information prospectively collected from 1447 patients (>18 years, median age of 57 years at diagnosis) with sporadic cutaneous melanoma at the Department of Dermatology of the Instituto Valenciano de Oncologia (IVO) in Spain from January 2000 to October 2015.  Patients with familial melanoma, extracutaneous melanomas or melanomas of unknown origin were excluded. Development of a second melanoma was the dependent variable in this study, which was evaluated as a time-dependent variable. Cumulative incidence was estimated based on competing risk models and the association of characteristics with the risk for a second melanoma was calculated using Cox proportional hazard models.

The findings revealed that after a median follow-up of 61 months, 3.8% of patients with sporadic cutaneous melanoma developed a second melanoma, representing a ratio of 1 in 26 patients. At years 1, 2, 5, and 10, the estimated cumulative incidence of second melanomas in the overall population was 1.6%, 2.3%, 3.3% and 6.7 %, respectively. When comparing patients with a single melanoma, it was observed that light hair color (blond and red hair), presence of more than 50 cherry angiomas and more than 100 common melanocytic nevi were independently significantly associated with the development of a second melanoma. The site and thehistological subtype of the first and second melanomas were not consistent. When tumor thickness was compared, it was discovered that the subsequent melanomas were thinner than the initial melanomas.

Limitations of the study include possible section bias as the data came from a single center, memory bias when collecting variables related to sun exposure, and no reliable estimates of long-term risk obtained from the short monitoring period.

The investigators concluded that their results can “help identify a subgroup of high-risk patients who might benefit from preventive measures, particularly education programs on self-examination and photoprotection.” The findings can also contribute to the implementation of specific monitoring protocols in this population, they wrote.

Reference

Pastor-Tomas N, Martinez-Franco, Banuls J, Penalver JC, Traves V, Garcia-Casado Z, et al. Risk factors for the development of a second melanoma in patients with cutaneous melanoma (published online March 12, 2020). J Eur Acad Dermatol Venereol. doi:10.1111/jdv.16341