Looking forward to going on a trip to the beach with friends this year. Already started getting in shape. Now I've been told I have cancer. How can I explain to them how I got it?

Wow! What a way to ruin a trip! some cancer can wait (prostate for instance), some wait for nothing (pancreas, glioblastoma). You may want to share, or perhaps you awnt to bow out quietly...You do not owe anyone explanations. A lot perhaps depends on your friends, but also your prognosis and what the treatment entails. Good luck with what you are dealing with!
Why explain. You did not say what cancer you have. More than likely, it was not some thing you did, unless you are smoker and drinker. Cancer occurs due to a combination of genetic susceptibility and environmental factors. Why do you feel the need to explain?

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Looking forward to going on a trip to the beach with friends this year. Already started getting in shape. Now I've been told I have larynx cancer. How can I explain to them how I got it?

A variety of thing. Depending on your age, laryngeal cancer is usually squamous cell carcinoma. Smoking, increased alcohol use, and even human papilloma viruses are implicated in causation. But, so is radiation in a few cases. In general, though, "cause" is not as easy to be sure about. Read more...