Infertile men may be twice as likely to develop male breast cancer than those without fertility issues, new research has suggested.
The study, published in Breast Cancer Research, also found there were significantly more men with no children among those who had been diagnosed with breast cancer.
Scientists at The Institute of Cancer Research, London (ICR), suggest the findings indicate further work is needed to understand the underlying causes of male breast cancer – something that is largely unknown.
The new research from the Breast Cancer Now male breast cancer study looked at 1,998 men newly diagnosed with the disease in England and Wales over a 12-year period.
About 370 men are diagnosed with breast cancer each year in the UK, and because male breast cancer is rare, research into the disease is usually limited to a small number of patients.
Studying a larger group of men enabled the team to show a statistically significant association between infertility and risk of invasive breast cancer in men.
The men were asked whether they had biological children, if they or their partners had ever experienced problems conceiving, or if they had visited a doctor or clinic for fertility concerns.
Researchers directly compared the fertility of the men with breast cancer to 1,597 men with no history of the disease.
While the biological reason is unclear, they discovered that men diagnosed with breast cancer were more likely to report fertility issues.
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Study author Dr Michael Jones, senior staff scientist in genetics and epidemiology at the ICR, said: “These are important findings linking infertility to breast cancer in men.
“Our study suggests that infertile men may be twice as likely as those without fertility issues to develop breast cancer.
“The reasons behind this association are unclear, and there is a need to investigate the fundamental role of male fertility hormones on the risk of breast cancer in men.
“We hope this could lead to insights into the underlying causes of male, and possibly even female, breast cancer.”
He added: “Breast cancer is often thought of as something that only affects women, but men can also be diagnosed with the disease.”
While men have breast tissue, which means they're still at risk of breast cancer, many men are unsure of the signs and symptoms to look out for.
Recent statistics from Insurancewith.com revealed that only 20% of men would see their GP immediately with common symptoms of breast cancer, whilst 78% of men believe there to be poor awareness of the disease.
Meanwhile, 24% of British men don’t think they will be diagnosed with the condition – rising to 42% in the 18-24 age bracket.
But though breast cancer in men isn’t overly common – Cancer Research UK suggest there are around 350 men diagnosed in the UK each year – increasing awareness of the disease is crucial to saving lives.
“While women are significantly more likely to suffer from breast cancer, it is an issue that can affect men as well,” explains Dr Jan Schaefer, chief medical officer at MEDIGO.
“In fact, men have a 1 in 1,000 chance of getting it and, while the risks are significantly higher for women, men should also be aware of any potential warning signs.”
The biggest concern for experts is the lack of awareness surrounding male breast cancer, which can often mean a late diagnosis.
“In cases of male breast cancer, once the condition is diagnosed, 30-40% of the time it is at a III or IV stage,” Dr Schaefer continues.
“At MEDIGO, a handful of the 80,000 patients we have helped were men with breast cancer and, unfortunately, all of them were already at a late stage, which supports the fact that there is a lack of awareness, not just amongst men but amongst their partners and caregivers too.”
Dave, 64, from Bristol was was diagnosed with breast cancer in 2015. He has since had a mastectomy, treatment and is now in good health but still taking drugs to reduce the chances of the cancer returning.
“I was on holiday in Florida, celebrating my birthday, when I found a lump on my chest in the shower," he says.
“It wasn’t painful and I didn’t tell anyone about it because life just seemed normal.
“I wasn’t aware that men should check for breast cancer, but I know that if your body changes, you shouldn’t leave it so I went to see my GP as soon as I got home and they referred me to see a specialist consultant.
“Despite being told it was probably just a fatty deposit, I had an ultrasound and biopsy. One week later I was diagnosed with breast cancer. The tumour was the size of a golf ball.”
He adds: “My mother died from ovarian cancer when she was 68 years old, and I knew there was a link between ovarian and breast cancer, but generally little is known about male breast cancer.
“People will say, ‘I didn’t realise men could get that’ and to be honest, I didn’t think I would ever get it.”
Male breast cancer: the facts
Dr Jan Schaefer, Chief Medical Officer at MEDIGO explains some of the symptoms men should be looking out for and when to seek medical help…
Not much research has been done into the causes of male breast cancer, as the chances of men having it are so much smaller. However, there are a number of factors that might increase the risk in men.
Family history and genetics could have a role to play. Men whose relatives had breast cancer are more susceptible to developing the disease in later years – especially in their 60s and 70s.
Other known factors include radiation exposure and increased levels of, or exposure to, oestrogen.
Oestrogen in men could be increased through medication, obesity and liver disease.
Additionally, alcoholism has been found to have links with breast cancer in men.
What to look out for
Given the fact that the male breast is typically smaller than a woman’s, this makes spotting any symptoms easier, which is why it is essential that men know exactly what to look out for, to catch the condition early and get the required treatment.
It is important to know how to check yourself for any early signs of breast cancer. Whenever you have the opportunity, whether in the shower or just before bed, press your fingers flat against your chest (right hand for the left pectoral, and left hand for the right) and move your fingers in a clockwise motion.
Check the entire area, starting from the outside and moving towards the nipple, looking out for any unusual bumps or lumps. An unusual lump is typically hard, not painful and doesn’t move around.
Once you’ve done this, check your nipples, looking out for any unusual discharge by gently squeezing each one in turn. You should also check for visual signs, such as the nipple turning inwards, a sore or rash around the nipple, or the surrounding skin becoming hard, red or blistered.
Lastly, you should also check your armpit for any unusual bumps, which can indicate swollen glands.
When to see your GP
The chances of men developing breast cancer are very low; however, if during a routine self-check you find any warning signs, like lumps, unusual discharge, rashes, or puckering of the skin, make sure to visit your GP.
If you and your family have a history of breast cancer, make sure to mention this during your visit, along with any of the symptoms that you are experiencing.
For more information on male breast cancer and the signs and symptoms of breast cancer to watch out for visit Breast Cancer Now.
Additional reporting PA.