My first kidney stone was in 1983, and I prayed that I would never have another one. It was a gut wrenching experience, to say the least. Thirty years later, a second one, but this one literally saved my life. The pain from the stone was severe, almost unbearable. In the ER they did a CAT scan to find the exact location of the stone, and in the process found a mass on my OTHER kidney. That mass turned out to be cancer, but at an early enough stage that I had no symptoms and it was fully contained within the kidney. I had to have a nephrectomy, where my kidney was removed, but that has been almost four years now with no cancer reoccurrence. I was told that 5 year survival for kidney cancer is about 15%, but in my case, because of how early it was found, my odds are 95% that the cancer will not return. So as bad as having a kidney stone is, sometimes there is actually a silver lining, even we don't normally think of cancer as a silver lining.