Tattoos may cause blood cancer: Inkings - no matter how big - could be linked to tumours years later. SOPHIE FREEMAN reports

More than a quarter of Britons have a tattoo — whether it’s for decorative or cosmetic purposes, such as permanent make-up; or medical purposes, such as nipple tattoos after mastectomies.

Now a new study suggests that having a tattoo may increase the risk of a type of blood cancer called lymphoma that affects around 14,000 people a year in the UK.

But should people be worried?

In the new study, researchers at Lund University in Sweden found that those with tattoos had a 21 per cent increased risk of lymphoma compared with those without.

The theory is that tattoos trigger low-grade inflammation, a known pre-cursor to cancer, but this is the first study to make a connection with tattoos.

A new study suggests that having a tattoo may increase the risk of a type of blood cancer called lymphoma that affects around 14,000 people a year in the UK

Dr Christel Nielsen, an associate professor in epidemiology, says tattoo ink can contain substances linked to cancer (i.e. carcinogens) such as heavy metals

A previous study in 2020 found no such link, while research in The Lancet in 2011 ruled an apparent link with skin cancer was nothing more than coincidence.

For the latest study, the Lund University team looked at everyone in Sweden who had been diagnosed with lymphoma between the ages of 20 and 60 between 2007 and 2017 (a total of 1,398 people) — and compared the results with people who had not had cancer.

Everyone completed questionnaires about their lifestyles and whether they had any tattoos — and if they did, how big the tattoo was, when they got it, and whether they’d had any removed.

The results, in the journal eClinicalMedicine, found the risk of lymphoma was highest in the first two years after getting a tattoo and then fell, but rose again 11 years later. Researchers had expected bigger tattoos to increase the risk — but this turned out not to be the case.

‘One can only speculate that a tattoo, regardless of size, triggers a low-grade inflammation in the body, which in turn can trigger cancer,’ said lead researcher Dr Christel Nielsen, an associate professor in epidemiology.

She added that when tattoo ink is injected into the skin, the ‘body interprets this as something foreign that should not be there and the immune system is activated’ — this is why the surrounding area becomes sore and inflamed for a while after getting a tattoo.

Previous studies have found a large amount of tattoo ink is transported away from the skin to the lymph nodes, the small bean-shaped structures that filter lymph (the fluid that surrounds all the cells in our bodies).

Tattoo ink can contain substances linked to cancer (i.e. carcinogens) such as heavy metals, and the cells in the lymph nodes are sensitive targets to these, says Dr Nielsen.

She adds that it’s possible those cancer-causing substances alter lymph node cells, which is what causes lymphoma, or it could be the immune system’s reaction to ink that’s to blame.

But getting rid of tattoos may not be the answer.

‘A few in the study had undergone laser therapy [to remove tattoos], but for them the risk seemed to be substantially higher,’ Dr Nielsen told Good Health.

‘We know that the laser breaks up the stable pigments into smaller molecules that can be removed from the skin. The molecules that are formed are likely more toxic and reactive than the original pigments, and they hit the lymphatic system the same way as the pigments do.’

The study found the strongest link for two types of lymphoma: diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma, which are both forms of non-Hodgkin lymphoma.

Around 5,000 people a year in the UK are diagnosed with DLBCL; slower-growing follicular lymphoma affects around 2,300.

The Swedish researchers stressed the findings did not prove tattoos triggered lymphoma, but ‘suggest tattooed individuals have an increased risk of lymphoma, which underscores the need for continued research into the long-term health effects of tattoos’. Now they are investigating whether tattoos increase the risk of other diseases, including skin cancer.

Dallas Pounds, director of services at the charity Lymphoma Action, said: ‘The survey indicated that people with tattoos had a higher adjusted risk [risk after removing other factors that could alter the results] of lymphoma, and this varied depending on several factors, such as the type of lymphoma and the time since having tattoos.

‘However, an association does not indicate a causal link. For the average person the risk of lymphoma is low, even when you take into account risk factors that increase the likelihood. The important thing is to be vigilant for symptoms.’

T he most common sign of lymphoma is swollen lymph nodes — a lump, or lumps, in the neck, armpit or groin — which persist for longer than a couple of weeks. (Most swollen lymph nodes are caused by the body’s normal infection-fighting response.)

Other symptoms are unexplained weight loss, night sweats, fatigue and an itch without a rash.

Dr Rachel Orritt, health information manager at Cancer Research UK, said: ‘There isn’t enough evidence to say that tattoos increase people’s cancer risk and more research is needed.

‘This is a difficult area to study, because there are lots of different ingredients in tattoo ink, making it tricky to understand the effects. If people are concerned about their cancer risk, there are proven steps they can take to reduce it.

‘These include not smoking, eating a healthy, balanced diet and cutting down on alcohol.’