2 Answers

There are different types of cancer. Read here > http://www.cancer.gov/cancertopics/cancerlibrary/what-is-cancer

Our bodies are rather complex and demanding. When some cells remember some ancient creature or find reproducing the old standard pattern less interesting, we call that oddity “cancer” and treat it medically to keep it under control, kill the group of maverick cells by a variety of ways, let it do its own thing for a while or remove it in some proven method. Such events in your physology could end your life abruptly or not bother you again. Some Doctors study these anomalies and may recognize their pattern of advancement if any. Doctors are trained in how to approprately deal with these conditions and should be consulted as soon as possible to find what course of action, if any, may be called for.