Please tell me what are some of the most least/dangerous cancers?

Most/least dangerous: There are many factors that affect the "dangerousness" of a cancer. Cancers like ovarian/pancreatic can be dangerous because they often are diagnosed after they have already grown or spread enough to cause symptoms. But they can also be found early, when they may be curable. Other cancers (eg prostate/breast) are often found on screening studies when they are still small and thus more curable.