Be mindful. Vitamin B17 won't destroy a tumor. B17 kills the malignant aspect (cells) of the tumor. The tumor will swell as the B17 releases its cyanide/benzaldehyde/sugar. The swelling is alarming, for those who don't expect it. Tumors are 90-95% benign, meaning: they don't shrink considerably when the cancer is gone. Surgery is required, after B17 therapy, if the tumor is impinging on nerves and/or blood vessels.