The Howard Stern Show's Robin Quivers on Living with Endometrial Cancer for Over a Decade: 'I'm Still Here' (Exclusive)

Radio personality Robin Quivers was out of town for a friend’s wedding in May 2012 when she started feeling unusually tired and recalls having trouble urinating.

“It was painful, it was scary, it was bizarre,” the long-time co-host of The Howard Stern Show tells PEOPLE in this week’s issue. 

After a trip to the emergency room, she learned a grapefruit-size mass was lodged in her pelvic area and staff told her, “As soon as you get home, see a doctor.” Days later she returned to New York City to see a gynecologist and a gastroenterologist, but a series of CT scans, MRIs and biopsies all came back inconclusive.

“Nobody was able to diagnose it,” recalls Quivers, 71. “They told me, ‘We really don’t know what this is. We can’t identify it without going in and getting it.’”

Surgeons later discovered the mass had been resting on “every organ” in her pelvic area, requiring a complete hysterectomy. “Then it was hours of meticulously scraping off layers of tissue and not destroying [whatever] organ it had been touching,” she says. 

Quivers spent weeks waiting for test results — and reviews from a new team of doctors — before being diagnosed with a rare form of stage 3C endometrial cancer.

According to the American Cancer Society, an estimated 66,000 women will be diagnosed with cancer of the endometrium (the lining of the uterus) this year, making it the most common gynecological cancer in the U.S.

Following her recovery from surgery, Quivers began a grueling 15-month regimen of radiation and chemotherapy. During those low points, she leaned on close friends, like Howard Stern, who she says “just surrounded me and made this network to take care of me. I never had to ask for anything. It was just overwhelming.” 

Quivers managed her six-week session of radiation with little difficulty, and, thanks to preventive medications, her six rounds of chemotherapy treatments went smoothly, with minimal side effects or nausea. “I was pretty tired, but I felt fine,” says Quivers.

Treatment for endometrial cancer is often a combination of surgery, radiation and chemotherapy. 

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Quivers was cancer-free for more than three years. However, she relapsed in December 2016. During a routine scan, doctors discovered Quivers’s cancer had returned and metastasized to her lymph nodes. “It’s never been a huge problem,” says Quivers. “When it’s shown some growth, then we have to manage that.”

Since she had stage 3, there was more than a 50 percent chance that it would come back and most likely require chronic treatment,” says Dr. Christina Annunziata, senior vice president of Extramural Discovery Science at the American Cancer Society, who did not treat Quivers.

Now, Quivers undergoes immunotherapy infusions intermittently, but she hasn’t let that slow her down. 

“That’s a very hard thing to do, to describe my health these days,” she tells PEOPLE. “When you’re in and out of treatment, you’re always recovering and trying to get back to where you were.”

“I feel fine. It’s been 11 years of dealing with this — and I’m still here,” adds Quivers, who has made several healthier lifestyle changes and even started traveling more. “I’m interested in everybody having a fuller life, more options and knowing what’s possible.”

For more on Robin Quivers, pick up the latest issue of PEOPLE, on newsstands Friday, or subscribe here.