The treatment isn't perfect, said Simone, but "you've got a very good chance (for survival)." Survival rates are about 70 percent (although in some of these cases the disease recurs 20 years later).

"They're playing with fire, these people," Simone said about the Jensens. "Every cancer is worse if it comes back. It's much harder to cure. It doesn't mean it's impossible, if it's caught in a very early relapse phase. It's maybe half (the cure rate) what it was before."

The Jensens have said they wanted to explore alternative therapies for their son. They had made an appointment at the controversial Burzynski Clinic in Houston — known for its antineoplaston therapy to treat cancer — but were unable to get an evaluation there after the state of Utah intervened.

The Cancer Cure Foundation of Thousand Oaks, Calif., lists more than 50 alternative therapies on its Web site but stresses that it "does not recommend the abandonment of conventional therapies in favor of alternative therapies."

Dr. Susan Silberstein, executive director of Center for Advancement in Cancer Education in Wynnewood, Pa., said she is sometimes contacted by families who balk at chemotherapy for their children.

"It's such a legal hot potato that what we've suggested is that they at least explore complementary therapy," Silberstein said. Complementary therapy, as opposed to "alternative" therapy, is the combining of conventional (in this case chemotherapy) and non-conventional therapies. These would include botanicals, vitamins, homeopathic medicine and play therapy, with the goal of enhancing the child's immune system, minimizing side effects and preventing recurrence.

"We've had some excellent successes (with alternative therapies), but 99 percent of the time we can't do it without also using conventional therapies" because of the legal ramifications, she said.

The goal, she said, is to avoid an antagonistic situation between families and medical professionals. So she encourages some families to do at least an initial round of chemo. For those who refuse, she encourages them to write a "disclaimer letter" to their doctor and hospital saying that the family respects their recommendation of chemotherapy but "at this time we accept full responsibility for a decision to work with another credentialed physician." This would be a medical doctor who also believes in alternative therapies, although she said "it's not easy to find people like that."

"We coach them how to write the letters. But we explain that they're really playing with fire," because they might still have the child removed from their custody, said Silberstein.