Ethan Zohn, cancer back, still running marathon

Ethan Zohn has battled competitors on the soccer field and on the set of the popular TV shows "Survivor" and "The Amazing Race." Now, the real-life survivor is facing the fight of his life -- again.

He was the survivor who not only triumphed in the network series of the same name, winning "Survivor Africa," but beat back Hodgkin's lymphoma, a cancer that attacks the lymphatic, or immune system. He was diagnosed with in 2009.

Zohn underwent intensive chemotherapy and radiation, keeping a video diary and shaving off his trademark curls before the chemo caused too much of his hair to fall out. After receiving a stem cell transplant and more radiation, he learned his cancer was in remission.

This year, Zohn and his girlfriend of eight years and fellow "Survivor" winner, Jenna Morasca, signed up for the "Amazing Race" that kicked off in September. The same month, Zohn learned his cancer had returned after 20 months of remission, localized in the lung area.

"I have to carry on, knowing I have the best doctors in the world and an incredibly supportive family and girlfriend in Jenna," he said.

He is now receiving a new chemotherapy treatment that only targets the areas affected, and he is still moving forward with his plans to run in the New York City Marathon on Sunday, refusing to let the cancer sideline him.

The couple stopped by "The Early Show" to tell how they're coping with the difficult news, yet trying to persevere.

Zohn says itchy skin led to tests that revealed the Hodgkin's lymphoma had resurfaced.

"One of the symptoms of Hodgkin's lymphoma is itchy skin with fever and night sweats and loss of weight, which I didn't have. I felt completely healthy and normal. We were filming a TV show, 'Everyday Health,' and our life was going great and then -- bang! You get slapped in the face," he said.

To fight through this once is one thing, but now to have to deal with it yet again is another. So, how is the couple coping?

"I think," Morasco said, "the first time we were like, 'OK. We are going to do this. We're going to clear our deck. We are going to make everything available.' Then, when you go into remission, you get your life back and you make plans, and we have things we wanted to do and, all of a sudden, it's threatened to be taken away from you again. You're just -- there is the flurry of emotions. It's almost more devastating."

"Angry and sad and scared, everything" Zohn adds.

But Zohn isn't going to let cancer take the New York City Marathon away from him.

"No way," he said.

"I've been training for months. My charity, Grassroots Soccer, we have 70 runners this year and raised $200,000 for HIV/AIDS, and there's some 'Amazing Race' racers on there, too."

How difficult was training for the NYC Marathon?

"The chemotherapy I'm on right now is pretty good. It's called SGN-35, and side effects aren't that bad, and it's targeted and smart therapy, and I've been training through it and feeling strong and healthy," he said.

The treatment this time around is localized and a little bit different. Is it more painful?

"So far, it's good. But, you know, it's called 'smart therapy' because it only targets the cancer cells," he explained.

"It's confusing, though," Morasca said, "because it only targets the cancer cells, so it doesn't destroy your body. You don't lose your hair, so he doesn't look sick, but inside, there is this epic battle going on. So it's really confusing, because he looks fine, but you have this kind of war going on inside, so it's really hard to kind of manage these two worlds."

Zohn is clearly a fighter, but so is Morasca. She has been there by his side the entire time. What advice can she offer for partners who are going through this?

"For every person fighting, there is someone helping out, a caretaker, and for me, it's being able to have a good support system and someone you can really break down to, to scream at, do whatever you need to do that you don't feel comfortable doing in front of the person you're taking care of. I think we all need that outlet and we need good friends and keeping your activities and keeping the things you love to do. Don't let cancer take anything away from you, you know? Just kick it out the door."

A lot of people know Zohn from "Survivor" and "The Amazing Race," and now he's running in the marathon, so they might assume he's a superhero in some sorts. But getting cancer a second time around is a whole different ballgame.

"I'm scared. Every single day, you wake up and you have the worst fears going through your head. But for me, you've got to take that crisis, you've got to take that moment, that negativity, and turn it into something positive. And for me, doing what I'm doing, going public, it's just sending a message of hope to everyone out there. The perception of cancer in the world is there are winners and losers. You either win and you beat cancer or you lose and you die. There are millions of people who are living with cancer and that's OK, too. I'm not a failure."

"I'd like to run (the marathon) better than last year -- four hours and 16 minutes -- but I'm guiding a blind runner this year, as well. But he's a fast runner, so there's no excuse, really!"

"I think long as you finish..." Morasca says.

"It's the act of running it that's more important," Zohn said.