I, too, was feeling healthy, without a single symptom that would give a clue of prostare cancer, and had negative DRE exams by both my family physician and urologist. To take things a bit further, my PSA blood test (2.5 ng/mL) was well within the normal range, but had spiked from the 0.6 ng/mL baseline the year before.
When we decided to do a prostate biopsy I was advised that there was a 10 to 20% chance that it was cancer. I wouldn't wish prostate cancer on any man but if you have it, it's good to find out asap, when a cure is possible. When symptoms are present it may already have spread.
On the bright side, I am already returning to normal functions only two months after surgery. Continence is good, though not perfect and the first stirrings of return to sexual function are evident.