Cancer remains hardly curable by modern therapies. The author narrates his research and practice for curative therapies to control cancer using natural products such as lignans. Beginning with cancer cases of successful treatment, the author elaborates on why cancer may develop in some people but not in others, how cancer should be effectively treated, what lignans can do to cure cancer without causing detrimental reactions to the immune or other physiological functions, and how a person can effectively prevent cancer without having to suffer from so many uncomfortable prohibitions in daily life. The author emphasizes that lignans are not super killers to control cancer. Instead of killing cancer, lignans redress malignancy by ameliorating the gut microbiome and removing the tumor microenvironment. For instance, suppression of malignant angiogenesis minimizes blood supply to cancer and thus starves the cancer, leading to its gradual shrinkage and eventual disappearance via programmed cell death processes. Lignans strictly suppress malignant angiogenesis and other cancerous molecular events in the tumor microenvironment. This book is written for a broad range of readers, including biomedical professionals and those without a medical background, to learn about a novel dimension of effective cancer control.