Imagine fighting for your life after a cancer scare... only to find out you didn't even have cancer in the first place.

Well, imagine no more: If you're a man getting a prostate biopsy, you're putting your life on the line -- because a new study finds the biopsy itself can double your risk of a life-threatening infection in the month after the procedure.

Researchers compared data on 17,472 older men who had prostate biopsies to that of 134,977 who did not, and found that 6.9 percent of the men who underwent the procedure were hospitalized in the 30 days afterward -- versus just 2.9 percent of the un-biopsied.

They also wrote in the Journal of Urology that biopsy victims suffered 2.3 times the infection rate of men who kept their prostates away from the pokers.

Adding insult to infection risk, the median age of men in the study was 73 -- or what even many mainstream docs will admit is well past the age of prostate worry.

The simple truth is that the cancer won't hurt most older men (or even younger ones... but that's a topic for another day) -- but the infections caused by the biopsies can be positively deadly, and it's not hard to see why: The rectum is a germ highway.

Fortunately, the traffic is usually one-way, so the bacteria never have a chance to get inside your body. That only happens when a sharp instrument -- like, say, a biopsy needle -- works its way through and pokes a few holes here and there.

Suddenly, the traffic isn't one-way anymore -- and the bacteria get a free ride right into your bloodstream.

One study earlier this year found that 2 percent of prostate biopsy patients battle sepsis, a potentially deadly infection of the blood. Another study found that nine out of every 10,000 biopsy patients die of infection in the month after.

Here's the cruelest part of that last number: These were all men who didn't even have the prostate cancer that the biopsy was supposed to detect... dead.

But even if they did have cancer, they never needed to fight and lose this infection battle -- because as I told you earlier, prostate cancer is simply not the killer it's been made out to be... especially for older men like the ones in this study.

It's one case where you're better off not knowing -- because sometimes, what you don't know really won't hurt you.