Andy Manson’s wife, Michelle, had to force him to go to the doctor. Manson, a broadband engineer from Reading, had been experiencing a stabbing pain in his left nipple for months. But he ignored it until December 2013, when it got so bad that Michelle insisted. “She said: ‘I don’t know what you’re playing at!’” Manson remembers.

The speed with which the GP referred him to the breast clinic at the Royal Berkshire hospital was Manson’s first inkling that something was wrong. “You figure it’s more than just a pain,” Manson, now 48, remembers. He was right. He had stage four breast cancer that had spread to his lymph nodes. Six years on, following a mastectomy, chemotherapy and radiotherapy, Manson’s cancer is in remission – and he is hugely thankful he listened to his wife. “I was lucky,” he admits. “I didn’t go to the doctor as quickly as I should have, but I got away with it and – touch wood – I’m in the clear.”

Often mistakenly viewed as a women-only disease, breast cancer can, and does, strike men, including Mathew Knowles, Beyoncé’s father, who went public with his diagnosis last week.

According to research from Breast Cancer Now, about 370 men are diagnosed with breast cancer every year in the UK (versus 55,000 women). Most will get the diagnosis between the ages of 60 and 70. Like women, they are more likely to develop it if they are obese.

Because men are more reluctant to visit GPs – and because of the misconception that only women can get breast cancer – their breast cancer is typically more advanced by the time it is diagnosed. “When men have a suspicious lump in their chest, they often disregard it,” says Prof Valerie Speirs of the University of Aberdeen, a cancer biologist who specialises in male breast cancer. “This means they usually present at a later stage than women and the cancer can be more difficult for clinicians to treat, because it’s spread to the lymph nodes or other parts of the body.”

“Men need to be breast aware,” says Grete Brauten-Smith, a clinical nurse specialist for Breast Cancer Now. She advises men to look out for breast lumps, which can be painless or close to the nipple, inverted nipples, sores on the chest or nipples that won’t heal, swelling under the arm or in the chest area, or nipple discharge, which may also be bloody. “It’s so important that they check their breast tissue, get to know any changes and report them to their GP.”

“It was such a shock,” Doug Harper, 57, from Plumstead, says of his breast cancer diagnosis. “I remember telling my mates and them saying: ‘What do you mean? Men can’t get breast cancer.’” Like Manson, Harper was cajoled into visiting the GP in January 2012 by his wife, after mistakenly thinking he had a cyst on his nipple. “She said: ‘Go to the doctor – this is getting annoying.’” When he took off his T-shirt, the doctor’s entire demeanour changed. Jokingly, Harper asked the doctor if it might be cancer. “He said: ‘It could be.’ I said: ‘Oh God.’”

Male breast cancer sufferers will find themselves in a system designed for women. When he was recovering from his mastectomy at Queen Elizabeth hospital in Woolwich, Harper’s wardmates asked what procedure he was in for. “I’d say I had a mastectomy for breast cancer, and they’d say: ‘That can’t possibly be right.’”

He was given the leaflet of a support group, but the wording only referred to female patients. Men attending breast cancer clinics will often be pegged as supportive partners, rather than patients. “You sit in the mammogram waiting room, and you’re the only bloke there,” Manson says. “You feel like people are looking at you, thinking you shouldn’t be there.”

At present, men are excluded from breast cancer clinical trials, although the situation is improving. “There’s more research into breast cancer in men than there was before. People are starting to realise that male breast cancer needs to receive the same kind of attention that female breast cancer has for years,” Speirs says. More work still needs to be done. “I’d like there to be more awareness of male breast cancer. Everything is a sea of pink.” (The international symbol for breast cancer is a pink ribbon.)

Having breast cancer as a man can be isolating in other ways. The cancer drug Tamoxifen’s side effects can include impotence, which men may find embarrassing or difficult to talk about. After being diagnosed in January 2012, Harper didn’t meet another man with breast cancer until July of that year, when he took part in a charity event.

“I made a beeline for him,” he remembers. “I just wanted to talk with someone else who had been through the same as me.” (Breast Cancer Now runs a matching service to connect male breast cancer patients with other men with the condition.)

Recently, when he was going for a routine mammogram – his cancer is in remission – Harper saw a young man in his 20s being screened. He wanted to pass on his details, but decided against it in case he alarmed him. “I’ve always wondered how he got on.”