Multiple Primary Melanomas: A Common Occurrence in Western Sweden

Area of Science:

• Dermatology
• Epidemiology
• Oncology

Background:

• Patients with a single primary cutaneous melanoma have an elevated risk of developing additional melanomas.
• Understanding the epidemiology of multiple primary melanomas is crucial for patient management and public health strategies.

Purpose of the Study:

• To describe the epidemiology of multiple primary melanomas (invasive and in situ) in Western Sweden.
• To analyze the incidence, timing, and characteristics of subsequent melanomas in a defined population.

Main Methods:

• Utilized data from the Swedish Melanoma Registry spanning from 1990 to 2013.
• Analyzed records of patients diagnosed with single and multiple primary cutaneous melanomas.

Main Results:

• Out of 11,254 patients with single lesions, 898 (7.4%) developed 2,037 multiple primary melanomas.
• Melanoma in situ constituted 47% of subsequent lesions, compared to 26% of first melanomas (p < 0.0001).
• The median time to diagnosis for a subsequent melanoma was 38 months, with 49% detected within 3 years.

Conclusions:

• A significant proportion of multiple primary melanomas occur in Western Sweden.
• Physicians and patients must maintain heightened awareness for new melanoma development, particularly within the initial years post-diagnosis.