Cancer is a symptom of a weakened immune system. The cure for cancer is to strengthen the immune system while killing the cancer cells using nutrition and supplements - and simultaneously detoxing the body with supplementation and enemas. Gerson Therapy has been around for a century.
But the american medical system has outlawed natural treatments for cancer, requiring doctors to use only the standard, modern protocol of Chemo, Radiation and Surgery, referred to by natural healers as Cut-Burn-Poison. Nutrition and metabolic processes are not taught in medical school. Most education is sponsored by Big Pharma and there is millions to be made in the Oncology industry. Phyisicians can even get large kickbacks in the chemo business. Doctors risk losing their license if they even counsel patients on nutritional therapies.
There is a plethora of information out there, Youtube videos can get you started, just search for "healing cancer naturally". Websites like GersonTreatment.com, Books like "The Cancer Revolution" by Dr. Leigh Connealy, "Chris Beat Cancer" by Chris Wark. Chris has a youtube channel called "ChrisBeatCancer" where he interviews doctors, scientists, and testimonials of people who cured their own cancer. I think his website and book are the best place to get started as he is becoming a hub of references and opportunities for Q&A. He always reminds us that cancer cells are ever present in our body - their job is to defend against things like toxins, and when overwhelmed, they form tumors, then when the tumors are overwhelmed or damaged, they metastisize (my layman's understanding of the process :)
Other good references, Dr. Stephanie Seneff who has discovered convincing trends between the meteoric rise of cancer, autoimmune diseases, autism and alzheimers since the introduction of Roundup in the mass market in 1990. ALso Dr. Zach Bush, M.D. Basic things like knowing that cruciferous vegetables contain Glutathione which is powerful to protect against the damage of glyphosate. Acetic acid (natural sources in lemons, apple cider vinegar) and all the anti-oxidant foods like berries, can kill cancer cells.
I could ramble on for pages here - just wanted to say that there is no mystery about what causes cancer, how to prevent it and how to cure it (in most cases when all conditions are corrected like stress, diet, chemicals in environment, and a spiritual BELIEF that one can be cured).