Entertainment exec Mathew Knowles: I have breast cancer

By American Heart Association News

Mathew Knowles at his office in Houston. He was diagnosed this summer with breast cancer and a genetic mutation that puts him at risk for other types of cancer. (Photo by Anzola Media for AHA News)
Mathew Knowles at his office in Houston. He was diagnosed this summer with breast cancer and a genetic mutation that puts him at risk for other types of cancer. (Photo by Anzola Media for AHA News)

HOUSTON – One night in July, entertainment executive Mathew Knowles peeled off his white undershirt and noticed a red dot on it. He thought it was lint. It wasn't, but he hardly gave the speck another thought.

The next night, he saw another red dot on his T-shirt. It was in the same area, near his right nipple. Although he laughs about being the kind of guy who wants an MRI to make sure a headache is only a headache, he continued to downplay it.

Days later, Knowles saw it again. He mentioned it to his wife. Come to think of it, she said, she'd seen red spots on their bedsheets in recent days.

Now Knowles was curious enough to squeeze his right nipple. Out came blood, beginning a series of events with potentially life-altering ramifications for himself and his family, including his daughters Beyoncé and Solange.

Knowles turned out to be one of the rare men with breast cancer. Further testing uncovered that he has a mutation of one of the so-called "breast cancer genes," specifically BRCA2.

That discovery may explain why he developed cancer in his right breast, and it means he's at a higher risk of developing other forms of cancer. He's already had a mastectomy of his right breast and is planning one for the left side to be safe.

Aggressive, proactive response to the risks associated with this genetic mutation became part of the national conversation years ago when actress Angelina Jolie learned that she had the BRCA1 mutation and opted for a preventive double mastectomy. She then had her ovaries and fallopian tubes removed to guard against ovarian cancer.

The fact that Knowles has the mutation gives each of his children a 50% chance of having it. If any females have it, their risks increase sharply for breast cancer and ovarian cancer.

As a longtime volunteer for the American Heart Association, Knowles knew he was fighting more than cancer, the No. 2 killer of Americans. Cancer patients can experience cardiac complications related to treatments including chemotherapy and radiation or as a result of the hormonal changes that follow procedures such as removal of the ovaries.

His relationship with the AHA is why he chose to reveal what he's been through with American Heart Association News in advance of his public disclosure Wednesday on "Good Morning America."

Knowles – who managed supergroup Destiny's Child and co-wrote their hit song "Survivor" – is sharing his story to draw attention to the links between heart disease and cancer, as well as other powerful messages:

– Men can have breast cancer.

– Genetic testing for mutations of the BRCA1 or BRCA2 gene is often wise for men and women of all ethnicities with a family history of breast cancer.

– Early detection improves the chances for a successful outcome.

"I don't want people to be worried – I want them to be proactive," Knowles said. "The sooner you address it, the better you have a chance of having a normal lifestyle and living a normal life."

So far, so good for Knowles.

Since the mastectomy, he's been exercising more, watching what he eats and drinking less alcohol. He's lost 15 pounds and hopes to drop 10 more. He's also begun taking medicine to control his blood pressure and meditating to manage stress.

At 67, he understands that prioritizing his health lets him enjoy a full life. In the coming months, he'll be releasing a book, album and musical about Destiny's Child. He also teaches a weekly class in sports, event and entertainment marketing at Prairie View A&M University in Texas.

"What is quality of life?" Knowles said. "It's not just money. It starts with health."


As a former college basketball player who's endured five surgeries related to his athletic career, Knowles has long been in tune with his body. A family history of heart disease and cancer also have helped him be vigilant with his medical care.

Still, when he squeezed his right nipple and blood emerged, his first thought was to find a simple reason for it.

Was he taking any new medicines? No.

"Did I hurt myself somehow?" he thought. "Could it be related to working out? Was it from something I ate? Are the cleaners using different chemicals?"

Once he eliminated those options, he considered breast cancer.

In addition to losing several relatives to it, the disease also was top of mind because his wife's mom is battling it and, in January, his wife's sister died of it. Tiffany Smith was 49. Her case made the news because her husband, Rick Smith, resigned as general manager of the NFL's Houston Texans to care for her and their three kids. Along the way, Knowles saw the toll breast cancer took on her and her family.

While he figured it unlikely that he had breast cancer, Knowles couldn't rule it out. So he tapped out a text to someone who could, his internist, Dr. James Muntz.


Muntz saw Knowles the next day. The doctor drained fluid from Knowles' right nipple and sent the sample for testing.

In his 35-year career, Muntz had seen only one male patient with breast cancer. He already feared that he was seeing another.

Still, neither he nor Knowles used the words "breast cancer."

"Mathew is pretty open about all this and seemed calm," said Muntz, who also is the team doctor for Houston's NFL, MLB and NBA teams. "But he was aware of what we were looking for."

In fact, Knowles was uniquely aware of how breast cancer is detected.


In 1978, Knowles was selling office copiers for Xerox when he learned about a job opening in the medical division. The position was selling xeroradiography machines, an imaging device used to detect cancer, especially in breasts.

He prepared for the interview by spending countless hours at the library. He learned all he could about breast cancer and the technology behind detecting it.

Talking the talk helped him land the job. It also helped him become the top salesman. He later went to Philips, where his first role was selling CT scanners and MRIs. He ended up spending 20 years in diagnostic imaging, leaving to oversee Destiny's Child.


When Muntz got results from the lab work, he sent Knowles for a mammogram.

Knowles managed to look at the scan.

"I could see it myself – a mass of less than 2 centimeters," Knowles said. "I knew what that meant."

A biopsy confirmed it was malignant. The mastectomy followed. Fortunately, the tumor was stage 1A, one of the earliest, and hadn't spread.

But where did it come from? Why was he among the mere 2,000 or so men in the country likely to get diagnosed with breast cancer this year?

Mathew Knowles after a mastectomy of his right breast. He also plans to have his left breast removed. (Photo courtesy of Mathew Knowles)
Mathew Knowles after a mastectomy of his right breast. He also plans to have his left breast removed. (Photo courtesy of Mathew Knowles)


Everyone has BRCA1 and BRCA2 genes. They're important, too. They help cells stay healthy by repairing damage.

A change in any gene is called a mutation. A change in either BRCA gene makes certain types of cancer more likely, especially breast cancer.

Because only 0.1% of men develop breast cancer but up to 10% of men with a BRCA mutation develop it, doctors often recommend male breast cancer patients undergo a simple blood test to check for those mutations.

"Ten percent is not high in general, but it's astronomically higher – up to 100 times – than for someone who doesn't have the mutation," said Dr. Susan Domchek, executive director of the Basser Center for BRCA at Penn Medicine's Abramson Cancer Center, the world's first comprehensive center aimed at advancing research, treatment and prevention of BRCA-related cancers.

Domchek also is part of Knowles' medical team. They were introduced by AHA officials.

Knowing Knowles had the BRCA2 mutation was a game-changer.

For instance, had Knowles known it sooner, he would've had a double mastectomy from the start. His risk of developing cancer in his left breast remains only as high as 10%. Considering how his odds have broken thus far, his attitude is, "Why even have a risk?"

He also knows his risk of developing prostate cancer has gone from about 11% to as high as 25%, so he's seeing a urologist. An MRI showed cause for concern, prompting further testing and monitoring.

Doctors also are paying close attention to elevated risks for cancer in his skin and pancreas.


The other crucial layer of Knowles knowing he has the BRCA2 mutation is what it means for his family.

Domchek frames it this way: "We often say that we don't test people, we test families, because of the implications for families."

Research is underway to determine which side of his family the mutation comes from. Anecdotal evidence makes it a toss-up.

On his mother's side, breast cancer claimed an aunt and two first cousins. On his father's side, an aunt recently was diagnosed with breast cancer, and prostate cancer claimed the lives of his grandfather and three uncles. Relatives from the affected side will get advice about what to do next.

Then there are his children and grandchildren.

In addition to each child facing a 50% chance of having the mutation, each grandchild has a 25% chance.

If any females have the mutation, their risk of breast cancer goes from 12% to 69%, and their risk of ovarian cancer goes from 1.3% to 17%. They will also need to monitor their skin and pancreas.

"I have let both Beyoncé and Solange be aware and know what's required," Knowles said. "They proudly do routine screening. … Fortunately, my daughters have a wonderful team of experts that have certainly been vigilant in making sure and ensuring that they're OK."


For every 10 women tested for BRCA mutations, only one man gets tested, Domchek said.

That makes it tougher for researchers. Tougher still is that among the men who get tested, most are white.

Knowles, therefore, can help break a lot of barriers for scientists and, ultimately, patients.

"An influential black man with breast cancer and the BRCA2 mutation? This is such an important story to share for so many reasons," Domchek said. "This powerful story will impact and inspire so many."

Knowles especially hopes his story resonates among African Americans, who often face numerous disparities in health and proper care.

After all, despite his extensive experience around cancer, he'd never heard of BRCA mutations until his ordeal. And he considers himself more fortunate than others. A case such as his could raise awareness and spur people into action.

Another way Knowles is trying to help is by joining the cohort of patients with a BRCA mutation being studied by Domchek's team.

"We want to figure out why he developed breast cancer when most BRCA2 carriers do not," she said. "The more we understand that, the more we can help others."


For several years, Knowles has closed speeches by telling about the time he was at the Los Angeles International Airport and a woman gave him a card that read: "Pray not for a life free from trouble. Pray for triumph over trouble. What you and I call adversity, God calls opportunity."

Now, he has a new appreciation for that sentiment.

"My opportunity is to help people have awareness of the BRCA gene (mutation) and of male breast cancer," he said. "Things happens for a reason. I'm grateful for this opportunity to save myself, hopefully save my family and hopefully impact the world in an extremely positive way."

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