- People with history of smoking have less effective immune system, study shows
- Those with genetic signs of a high immune system also affected if they smoked
- Researchers said the findings stress the importance of quitting after diagnosis
Smoking cigarettes stops the body from fighting deadly skin cancer, according to research.
Smokers and former smokers are 40 per cent less likely to survive the disease ten years after diagnosis than those who have never smoked.
A connection between smoking and the bodies response to melanoma, most commonly caused by exposure to the sun, has not been previously found.
The immune response of smokers appears to work, but is less effective, researchers at the University of Leeds said.
They stressed the importance of people dropping the habit, especially if they are fighting the skin cancer, which has shown to be on the rise in the UK in recent years.
Professor Julia Newton-Bishop, lead author of the Cancer Research UK-funded study, said: ‘The immune system is like an orchestra, with multiple pieces.
‘This research suggests that smoking might disrupt how it works together in tune, allowing the musicians to continue playing but possibly in a more disorganised way.’
The study used data from more than 700 patients with melanoma, which takes the lives of 2,000 in the UK every year, and 9,000 in the US.
The research, published in the journal Cancer Research, found that people who have smoked have a 40 per cent lower survival rate.
People who had any history of smoking were found to be at greater risk of dying of melanoma – they do not have to be smokers at the time of their illness.
However the researchers did not specify how many cigarettes would impact a person’s health.
The smokers and past smokers were compared to people who had never been hooked on cigarettes.
In a small group of 156 patients who appeared to have genetically better immune systems, smokers were around four-and-a-half times less likely to survive than non-smokers.
Given that reduced survival was found to be greatest for smokers in the group with most indicators of immune cells, the researchers think that smoking could directly affect how smokers’ bodies deal with the melanoma cancer cells.
However, due to the study design, they cannot prove that smoking was the cause in the drop in survival.
Professor Newton-Bishop said: ‘The result is that smokers could still mount an immune response to try and destroy the melanoma, but it appears to have been less effective than in never-smokers, and smokers were less likely to survive their cancer.
‘Based on these findings, stopping smoking should be strongly recommended for people diagnosed with melanoma.’
Dr Julia Sharp, head of health information at Cancer Research UK, said: ‘Overall, these results show that smoking could limit the chances of melanoma patients’ survival so it’s especially important that they are given all the support possible to give up smoking for good.’
Scientists are have reported in the past the adverse effects smoking has on the immune system, but it’s not yet known which chemicals are responsible.
There are no UK-wide statistics available for melanoma survival by stage.
In England and Wales, more than 90 per cent of people will survive their cancer for 10 years or more after diagnosis, according to Cancer Research UK.
Generally survival rates are lower for men, possibly because they are less likely to see a GP about their symptoms in the early stages.
WHAT IS MELANOMA AND HOW CAN YOU PREVENT IT?
Melanoma is the most dangerous form of skin cancer. It happens after the DNA in skin cells is damaged (typically due to harmful UV rays) and then not repaired so it triggers mutations that can form malignant tumors.
The American Cancer Society estimates that more than 91,000 people will be diagnosed with melanoma in the US in 2018 and more than 9,000 are expected to die from it.
Around 15,900 new cases occur every year in the UK, with 2,285 Britons dying from the disease in 2016, according to Cancer Research UK statistics.
- Sun exposure: UV and UVB rays from the sun and tanning beds are harmful to the skin
- Moles: The more moles you have, the greater the risk for getting melanoma
- Skin type: Fairer skin has a higher risk for getting melanoma
- Hair color: Red heads are more at risk than others
- Personal history: If you’ve had melanoma once, then you are more likely to get it again
- Family history: If previous relatives have been diagnosed, then that increases your risk
- Removal of the melanoma:
This can be done by removing the entire section of the tumor or by the surgeon removing the skin layer by layer. When a surgeon removes it layer by layer, this helps them figure out exactly where the cancer stops so they don’t have to remove more skin than is necessary.
- Skin grafting:
The patient can decide to use a skin graft if the surgery has left behind discoloration or an indent.
- Immunotherapy, radiation treatment or chemotherapy:
This is needed if the cancer reaches stage III or IV. That means that the cancerous cells have spread to the lymph nodes or other organs in the body.
- Use sunscreen and do not burn
- Avoid tanning outside and in beds
- Apply sunscreen 30 minutes before going outside
- Keep newborns out of the sun
- Examine your skin every month
- See your physician every year for a skin exam
Source: Skin Cancer Foundation and American Cancer Society