As the nation remembers the lives lost during the terrorist attack on September 11, 2001, some are working to bring awareness to first responders and others still suffering from 9/11-related illnesses.

"We're only now beginning to understand and witness the long-term effects of that work and the full extent of the sacrifices of all of our first responders," FBI Director Christopher Wray said at the 9/11 Memorial & Museum in New York City last week.

This comes at the same time a New York City law firm claims to have around 15 male clients who are suffering from breast cancer believed to be linked to the toxins from Ground Zero.

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Jeff Flynn is one of those clients. He worked for a data storage company near the World Trade Center site and helped many financial firms get back on their feet. A decade later, he was diagnosed with stage III breast cancer.

"I thought it was a cyst or a gland and I ignored it for a while," he told CBS News. "And that was the wrong thing to do because it spread to my lymph nodes."

Flynn's doctors excised 35 lymph nodes during surgery. Thirty-four of them were cancerous. "The diagnosis was pretty bleak at the time," he said, but after receiving treatment and then going through a relapse, he is currently cancer-free.

John Mormando worked as a commodities broker in the World Trade Center area until 2007. He was preparing to compete an Iron Man race when he noticed a lump on his chest.

He went in for testing soon after and learned he had breast cancer.

"I was totally floored," Mormando said. "We know breast cancer is a popular disease, unfortunately, but for men, it's very rare. And I had it in both breasts, believe it or not."

Breast cancer is, indeed, very rare in men. According to the American Cancer Society, men have a 1 in 833 risk of developing breast cancer in their lifetime — compared to about a 1 in 8 lifetime risk for women. It is 100 times less common among white men than white women and 70 times less common among black men than black women.

Several studies have brought attention to the health risks of 9/11-related exposures.

A study published in The Lancet in 2011 found that New York City firefighters exposed to the 9/11 World Trade Center disaster site were 19 percent more likely to develop cancer in the seven years following the attacks as their non-exposed colleagues and up to 10 percent more likely to develop cancer than a similar sample from the general population.

Another study published earlier this year in JAMA Oncology concluded that those exposed to the World Trade Center site, including firefighters and recovery workers "will experience a greater cancer burden than would be expected from a demographically similar population."

"This underscores the importance of cancer prevention efforts and routine screening in WTC-exposed rescue and recovery workers," the authors wrote.

However, the potential link to cancer is not without some debate.

In a JAMA Oncology editorial also published this year, Dr. Otis Brawley, the American Cancer Society's Chief Medical and Scientific Officer, brought attention to concerns around relatively small sample sizes and the fact that other research has shown that firefighters nationwide are at a higher risk of many diseases, including cancer.

But Flynn and Mormando's attorney, Michael Barash, argues that the link is undeniable.

"They'd never seen jet fuel – for 99 days it was cooking all the phones the computers, the concrete dust. They measured the pH level of the concrete dust. It was the same as Drano," Barash said.

Mormando described what it was like to work in the area at the time.

"The smell was horrific but we were told that the air quality was OK," he said. "Politicians said go back to work, you're doing fine. They called us heroes and we all ate it up and said we're doing the right thing getting back to work."

Former head of the Environmental Protection Agency Christine Todd Whitman later admitted she was wrong to call Ground Zero air quality safe after 9/11.

The World Trade Center Health Program, established by Congress, provides treatment for a specific list of physical and mental health conditions that have been determined to be caused by exposure to the 9/11 terrorist attacks. The program covers 68 cancers, including breast cancer.

For their part, Flynn and Mormando want to raise awareness about male breast cancer.

"We want to get the word out to other men because it is very rare and men tend to ignore it and don't see a physician," Flynn said.

Mormando recommends men talk to their doctor about breast cancer risk. "When you go in for your yearly physical, most men are programmed to get certain tests like prostate exam. … Just get a breast exam, too, especially if you were in the 9/11 area because you're at such a higher risk," he said.

Flynn works with support groups to provide resources and counsel to other men who have been diagnosed with breast cancer.

"I swore that if I survived this disease I would help other men," he said. "Once you're diagnosed, it's very lonely. There's not a lot of [resources] for men. Somebody helped me and I believe that the people I've tried to coach through this appreciate the support."

More information on the World Trade Center Health Program and the September 11th Victim Compensation Fund is available online.