ORLANDO – Unlike the imaginary monsters of our childhoods, the ones lurking under the beds, in the closets or outside the windows on moonlit nights, the monster haunting Deborah Romero is real.

She had rounds of chemotherapy followed by radiation therapy to get rid of it. She fought it when she was bedridden and wheelchair-bound, too weak and in too much pain to stand up.

And finally one day, all the scans and medical tests told her that she had beaten it. The Stage 4 non-Hodgkin lymphoma was gone.

But the monster still lurks.

"If I feel a pain in an area of my body, I panic. I get headaches and I wonder if it's gone up to my brain," said Romero, 50, who finished treatment four months ago. "It's so frightening. … It messes with your head."

For Romero and many others, cancer — the C word, the Big C, the unmentionable — doesn't just go away, even after the invasive cells are fried and killed. The fear of recurrence can engulf many survivors for the rest of their lives.

"People say, 'You're finished, right? You're back to normal.' But, no, that is largely never the case," said Kristine Donovan, who sits on the board of directors for the American Psychosocial Oncology Society and is a clinical psychologist at the Moffitt Cancer Center in Tampa, Fla.

There are nearly 14.5 million survivors living in the United States, and that number is expected to grow to almost 19 million by 2024, according to the American Cancer Society.

As people live long after their diagnosis, it has become clear that cancer is a chronic illness, and there are physical and emotional side effects that manifest themselves after the survivors are given a clean bill of health. Guidelines now recommend that oncologists give patients survivorship care plans to address needs and concerns after treatment and for follow-up care.