While screening can sometimes catch the very aggressive kind in time, I've read that it can often develop and metastasise in the year between annual screenings. It's almost a different disease: my oncologist told me it represents about 1 in 20 prostate cancer cases, and most typically appears in people of African or Caribbean ancestry (which I'm not).

In my case, there was was nothing visible in my prostate. They were trying to figure out where the metastasis on my spine had come from, and CT and MRI showed a perfectly-normal prostate with no signs of tumours and normal volume. After the tumour biopsy showed prostatic origin, they gave me a DRE, and the urologist thought -- just, maybe, not sure -- he *might* have felt a tiny nodule, but he didn't sound too confident.

In my case, that sucker just escaped the prostate almost as soon as it was born and made a beeline for my spine. That's what I mean by two different diseases ­— with the really aggressive kind, you might not have the luxury of years, or even months, to catch it early. And just coincidentally, for a week I was sharing a hospital room with an army vet (also not of African or Caribbean ancestry) who'd had the same experience: he was getting annual PSA screenings, and his prostate cancer just appeared out of nowhere and almost instantly metastasised.