Do B17 kernels prevent cancer?

Well it hasn't for me, today I've had two mole like growths taken off from my scalp and in the new year a further basel cancer lesion from my forehead is to be operated on. I've been taking kernels for several years since attending a Credence.org meeting combined with a fluoridation meeting in Dorset where Philip Day gave a convincing explanation of what cancer was and the benefits of B17. Take eight a day and if you have no symptoms you wont develop cancer. I didn't have then but I still got cancer.
How many other people have developed cancer after taking kernels for years. I sent an e-mail to Phillip and Credence.org asking if they ever received negative reports but I had no response.
Hopefully the mole like growths may turn out to be benign and the basel cancer is the least aggressive cancer you can get so maybe I'll live a few more years yet. But for a believer of alternative medicine it is a bit of a disappointment.
Bill