I am not a doctor this is my knowledge gained through my experience with my father's colon cancer and all the information I learned during and since. Thankfully, he is in Remission. Every person has cancer cells but not everyone develops it. Our choices matter. Disease or disease free. We must take responsibility of what we input into our mind, body and spirit. Why do you think you have cancer? We need to resolve and get to the root cause to dissolve it. Definitely, if you are diagnosed with Cancer a lifestyle change is necessary!
Nourish: You are what you eat or actually you are what you absorb. If you eat junk you will be junk. Sugar is a toxin, cancer feeds on sugar (Obligate Glucose Metabolizer) so one must take out sugar for sure. Flour destroys our gut lining and distorts our hormones. Processed foods, our bodies simply can't digest correctly. Get rid of sugar, flour and processed foods. Nutrition is the key and foundation to our health. Cancer is an immune system failure so one must ehance the immune system. Enhance your immune system with nutrient dense whole foods such as cruciferous veggies and also include powerful immune modulating herbal support such as lingzhi and cordyceps.
Detox: We need to reduce any toxicity of the mind, body, spirit. Aside from toxic food, reduce other toxins such as environmental toxicity (herbicides, pesticide, chemicals, pollutions, mercury etc!) and especially internal negative emotions/energy. How do we detox? Easy! as nature intended. Sleep more (heal & repair), drink more (pee it out), breathe more (exhale it out), fiber more (crap it out), move more (sweat it out) and most importantly get rid of stress/negative emotional energy (convert to positivity). Herbs that are adaptogens can support this process by helping you relax more and adapt to stress. Some herbs such as Reishi/Lingzhi are also known to even support your spirit. Reishi/Lingzhi is an incredible herb which supports all major organs. In addition, it is revered because it is known for making our immune system smarter. Please do look into it.
Chemotherapy:  I believe the chemo almost killed my dad, I tell people my father survived the chemo process not cancer. He lost all is bowel movements, at one point he was so weak we had to wait weeks for his next treatment. I started asking people their experience with chemo and much to my sadness several people told me they believed the chemo not the cancer killed their love ones. So of course I asked my dad to stop after finding these frightening stories - who would have known this was the start of my optimal wellness journey! So what I believe saved him was that we kept his immune system strong, did our best to keep him nourished, stayed away from sugar, we tried to laugh lots even when it wasn’t funny and the best attitude my dad had was that he would say cancer, what cancer, I don’t have cancer! Truth About Cancer statistics noted that the survival rate of chemo is 2%, even if you find that the number is slightly higher or significantly higher it is obviously still an abysmal statistic.  I found out after the fact that there are many alternative ways of going into remission but here in the US doctors are instructed to only inform us about chemo & surgery. If you are diagnosed most likely you have had that cancer for years, don't let their scare tactic rush you into a decision. Please do some research and you will be surprised how many choices we have - the Truth About Cancer series documents different approaches.
If we were to do this again, we would have added medicinal mushrooms and herbs such as Lingzhi and Cordyceps, taking in tremendous amounts of  cruciferous vegetable - we would have gone mostly vegetarian, getting protein from beans and not from pork, beef and chicken. Adding in movement meditations such as Qigong, Taichi and/or Yoga as cancer cannot live in an oxygenated environment as cancer is an Obligate Anaerobic Metabolizer. Definitely take out any sugar, flour and processed foods and other environmental toxins.
The above should not be interpreted as medical advice, and is not intended to diagnose, treat or cure your condition, or to be a substitute for advice from your physician or other healthcare professionals. The methods discussed here are intended to support health and healing, not to be a medical treatment. Whether you choose conventional treatments, alternative treatments, or both, work closely with the doctor or healthcare professional to properly diagnose and treat your condition, and monitor your progress.