Melanoma on Tattoos: Two Finnish Cases

Permanent tattooing, has gained tremendous popularity for the past 20 years among the Western population. In Europe, the prevalence of tattoos is estimated around 10% (1, 2), with the highest prevalence among the 20-35 years old (25%) (2). In Finland, it is currently estimated that 15% of the 20-30-year-old individuals are tattooed (3). Tattoo inks are currently a combination of organic dyes, metallic salts and various additives including solvents, such as isopropanol, and preservatives (4). Several publications have shed light on possible toxic or carcinogenic compounds that could be introduced in the skin or develop in situ as by-products under various conditions (such as UV light or laser exposure) (5-8). It is only recently that European countries and the council of Europe have started to take actions regarding the tattoo ink marketing, especially by withdrawing some inks that contained potential hazardous components from the market (9). However, the composition of tattoo inks is still not subjected to a strict homogenous regulation. Also, there is currently no test available to assess the safety of inks for the purpose of tattooing. Despite accumulation of the dye to local lymph nodes, which is a well-known consequence of tattooing (7, 10), the potential local and systemic carcinogenic effects of tattoos and tattoo inks remain to date unclear. We report here two additional cases of melanoma that developed on tattoos in two Finnish patients.