None of the options Charles Edgington's doctor presented after diagnosing him with prostate cancer included flying to Puerto Vallarta to have the disease annihilated by a robotic ultrasonic probe that heated his prostate to 212 degrees. The options did include confiscating the whole walnut-looking gland altogether, or freezing it with cryotherapy, or radiating it externally, or permanently implanting a hundred radioactive pellets—all standard and highly successful approaches that require long recoveries and carry better than even odds that Edgington, a 67-year-old retired state trooper from Swayzee, Indiana, would be left impotent or in diapers, or both. "If you look at the possible side effects, they are less than ideal," he said.

So Edgington, one of the 225,000 men diagnosed with prostate cancer in the United States last year, went home to cruise the Internet in hopes of finding an alternative that would leave his equipment functioning the way he preferred and frequently enjoyed. He quickly discovered high-intensity focused ultrasound, or HIFU for short, an experimental prostate cancer treatment in the United States that is already widely accepted in Europe, Asia, and Central America, precisely because the odds of impotence and incontinence are slim compared to the standard treatments.

US HIFU, a company based in Charlotte, North Carolina, is working to get FDA approval for the treatment within the next two years, but in the meantime it is arranging for patients like Edgington to fly to centers outside the country where they can be treated by Dr. George Suarez, a Miami urologist and the company's medical director. Suarez became a proponent of HIFU four or five years ago after searching for alternative options for his patients, since the outcomes using the standard treatments often proved worse than the disease itself. "Regardless of what treatment you use, the chances of survival are very good," Suarez said. "But being impotent is not an acceptable compromise. Being in diapers isn't either. There are quality-of-life issues you have to contend with. Would you rather have sex or be alive? Go ask a hundred guys and you'll be surprised what you hear."

So Suarez helped start US HIFU, a partnership with Focus Surgery, an Indiana company that makes an ultrasound machine called the Sonablate 500. It looks like a unit one might typically find an obstetrician using to locate a baby inside a woman's belly. The critical difference is that the Sonablate 500 is about a thousand times stronger, emitting energy through a robotic probe that narrows in on cancerous cells and heats them to death. Patients lie on their backs with their feet in stirrups, causing a strange and not entirely positive spiritual connection to their wives' pelvic exams.

In the case of HIFU, once the probe has been inserted, locked into place, and aimed directly at the prostate, the doctor fires up the computer's software, sending a signal to the probe to start mapping the cancerous gland. An image is transmitted to the monitor and the doctor selects the areas he wants to hone in on and destroy. Battle is waged with incredible precision: The cancerous cells are annihilated while the tissue and important nerve endings just millimeters away are left unscathed. "It's like a GPS smart bomb," Suarez said. "Imagine having a 2,000-pound bomb and saying, 'I'm gonna launch this thing at the front window of the second floor, and take out everything there, but nothing else.'" Two to three hours later, the procedure is done.

While there have been few large-scale, long-term clinical trials on the procedure, some smaller studies of the Sonablate 500 and another HIFU machine used in Europe have shown that between 70 and 90 percent of patients remain disease-free for at least six years. That's about the same as for the standard treatments. But of the 400 or so patients US HIFU has treated so far, Suarez said that fewer than 1 percent have experienced impotency or become incontinent.

The $20,000 treatment is not yet covered by American insurance companies, so Edgington opted for an installment plan and boarded a plane headed to Mexico with his wife and daughter. Except for the few hours he spent with the US HIFU team at the hospital, the trip was like any other vacation: The family stayed at a resort, took in the scenery, and swam in the ocean. The day after the procedure, Edgington and his family walked a mile down to the marina and went sailing for hours. "I really couldn't believe it," he said. "I felt fine. I thought it was too good to be true."

The other day Edgington went back to the doctor for a check-up. The cancer is nowhere in sight.