Skin cancers and lymphoma may be more prevalent among individuals with tattoos compared with those without tattoos, according to a recent study published by Clemmensen et al in BMC Public Health.
Prior research has shown that tattoo ink does not just remain at the site of injection—instead, when tattoo ink penetrates the skin, some of the particles from the ink can migrate to and accumulate in the lymph nodes.
Study Methods and Results
Investigators used data from over 5,900 twins in the Danish Twin Tattoo Cohort to examine tattoo patterns alongside cancer diagnoses. They sought to determine whether tattoo ink may trigger chronic inflammation in the lymph nodes, which could lead to abnormal cell growth and an increased risk of cancer. Analyzing the direct effect of tattoo ink on the risk of cancer is often challenging because cancer can take years to develop, meaning that exposure in youth may not lead to the development of cancer until decades later.
“We can see that ink particles accumulate in the lymph nodes, and we suspect that the body perceives them as foreign substances,” stressed co–study author Henrik Frederiksen, PhD, Clinical Professor at the University of Southern Denmark and a consultant in Haematology at the Odense University Hospital. “This may mean that the immune system is constantly trying to respond to the ink, and we do not yet know whether this persistent strain could weaken the function of the lymph nodes or have other health consequences,” he added.
The investigators found a higher occurrence of both skin cancers and lymphoma among the individuals who were tattooed. The link between tattoos and cancer was most evident among those with tattoos larger than the palm.
After accounting for age, timing of the tattoo, and how long the participants were followed in the study, individuals with large tattoos had nearly three times the risk of developing lymphoma compared with those who did not have tattoos.
“This suggests that the bigger the tattoo and the longer it has been there, the more ink accumulates in the lymph nodes. The extent of the impact on the immune system should be further investigated so that we can better understand the mechanisms at play,” detailed lead study author Signe Bedsted Clemmensen, MSc, PhD, Assistant Professor of Bioastatistics at the University of Southern Denmark.
Additional data from the Danish Twin Tattoo Cohort showed that tattoos may be becoming increasingly common. The investigators estimated that about 40% of women and 30% of men will have tattoos by 25 years of age.
Previous research also argued that certain pigments in tattoo ink may be more likely to cause disease than others. “In our study, we do not see a clear link between cancer occurrence and specific ink colors, but this does not mean that color is irrelevant. We know from other studies that ink can contain potentially harmful substances, and for example, red ink more often causes allergic reactions. This is an area we would like to explore further,” Dr. Clemmensen continued.
Conclusions
“The unique aspect of our approach is that we can compare twin pairs where one has cancer, but they otherwise share many genetic and environmental factors,” emphasized senior study author Jacob von Bornemann Hjelmborg, MSc, PhD, Professor of Biostatistics at the University of Southern Denmark. “This provides us with a stronger method for investigating whether tattoos themselves may influence cancer risk.”
The investigators plan to explore how ink particles may affect the function of the lymph nodes at a molecular level and whether certain types of lymphoma could be linked to tattoos more than other types.
“We want to gain a better understanding of the biological mechanisms—what happens in the lymph nodes when they are exposed to ink particles over decades? This can help us assess whether there is a real health risk and what we might do to reduce it,” Dr. Clemmensen concluded.
Disclosure: For full disclosures of the study authors, visit bmcpublichealth.biomedcentral.com.
