This information in this post was gathered from the most recent version of Cancer Facts and Figures 2013, published by the American Cancer Society.
    New cases of cancer projected for 2013 are primarily of the lung, breast, colon/rectum and prostate. The biggest killers, based on my quick scanning of the number projected to occur and the number projected to cause death, are lung, colon and pancreas.  The number of new cases of pancreatic cancer are a quarter that of lung cancer, and 13% them will die.  Half the lung cancer patients will also die (slightly more men than women).  Tobacco is expected to contribute to 174,100  of the 2013 cancer deaths (most will be from lung cancer).  In the American Cancer Society report, a chart showing the trends for cancer death rates  is remarkable in its depiction of lung cancer.  It trends up for both men and women, hitting a peak for men about ten years earlier - and has been declining in men from about 1990 and more recently for women.  A review of the research on smoking suggests that these trends are related to when men and woman started to smoke (different era) and when they started to quit.  It is the kind of graph that smoking friendly countries need to consider.  The incidence of cancer comes some ten to twenty years after smoking rates pick up.
   We lack effective treatments for pancreatic, lung and colon cancers.  However, colon cancer is one that can be prevented, like cervical cancer, by regular screenings which identify pre cancerous lesions that can be removed.  (Breast cancer is one that continues to occur but kills less people because of treatment options)
   What is most important from my position in public health is that as much as 33% of the projected new cancer cases could be prevented because they are associated with poor diet, overweight/obesity and lack of physical activity.  
   Cancers that are caused by infections, such as HPV, HBV, and HCV may be avoided with vaccines.  HIV related cancer can be reduced by preventing the transmission of HIV through safer sexual contact.
   Other risks for cancer include genetic and environmental.  Usually a series of events occur before cells mutate into cancer.  We are getting better at finding cancer sooner, but it can be as many as ten years from an exposure to a diagnosis (think smoking, suntanning, CT scans, phthalates in plastic, etc).
   There is so much more to tell you, and I regret not having the time to really dive into this report - as I have in years previous. Instead, I strongly encourage you to open this document.  The introduction alone is worth its length in gold.  It explains what cancer is, what may lead to it,  how it is diagnosed and staged and what certain terms like life time risk and relative risk mean.  
   Briefly, the life time risk of developing any type of cancer is about 44% for men and 38% of women.  This is in general and does not take into account any of your individual risks or protective factors (i.e., it could be higher or lower for you).  The life time risk for a certain cancer maybe higher or lower than those numbers as well.  Relative risk, as explained in the document, is when you compare a persons risk to someone elses - someone who may be different.  For example, the relative risk of lung cancer between smokers and non smokers, or colon cancer between those who eat a plant based diet and those who eat a meat based diet.
   Please take the time to look at the document.  I know you have heard about this on the news lately - or seen newspaper articles, but its not the same as "being there".