The American Cancer Society has happily announced that cancer deaths have declined for the second straight year. This is big news -- mostly because our population is growing and aging and it's entirely possible this could have led to an increase in cancer deaths. Not only is this not true, but the drop in deaths for this second year is eight times greater than the drop during the first year. Amazing.

It's hard to imagine in light of this great news that there are still less hopeful statistics out there on the cancer front. But there are so many dimensions to this disease -- prevention, detection, diagnosis, treatment, survival -- that the numbers can vary tremendously depending on perspective.

From the perspective of diagnosis, one in two men and one in three women in America today will develop cancer during their lifetimes. These staggering statistics, based on data collected during 2001 through 2003, are detailed in a pivotal paper appearing in The Oncologist -- a monthly peer-reviewed journal for doctors devoted to cancer patient care.

Dr. Matthew Hayat and colleagues, who worked on this paper for the National Cancer Institute, reveal other worrisome numbers and facts.

It seems the number of new cancer patients is expected to more than double from the current 1.36 million in 2000 to almost 3 million in 2050. Five-year survival for all cancer stages combined ranges from as low as 16 percent for lung cancer patients to 100 percent for prostate cancer patients. And black Americans are reported to have the highest cancer incidence and mortality rates for men and women for all cancers combined.

So while less people are dying from cancer, diagnosis of the disease seems to be on the rise. Not exactly a perfect scenario -- but if science and research can keep up, perhaps those diagnosed with cancer will need to prepare not for death, but for the management of a chronic condition.

All cancers are not treated equally. Some attract a frenzy of attention -- breast cancer -- and some receive not much attention at all -- gallbladder cancer. Some are vigorously researched and studied. Others sit by idly, rarely the subject of investigation. Some are feverishly funded. Some never prosper by way of financial support. Yet they all share something very important in common. They are all cancer.

All cancers are marked by an uncontrollable division and spread of abnormal cells. And they are all capable of delivering shock and despair and even death to any one of us. And that makes each one -- brain cancer, cervical cancer, colon cancer, eye cancer, liver cancer, prostate cancer, stomach cancer, you name it -- worthy of equal attention.

And so I bring to you Cancer by the Numbers, a series of posts that will feature the basics about all sorts of cancer, beginning with the numbers -- the statistics -- to help define the prevalence of each cancer, followed by important facts about screening, diagnosis, treatment, survival, and more. I will cover the well-known cancers, the sort-of-known cancers, the barely-known cancers. And while I can only offer what I can track down on each form of cancer, I intend to dish out every piece of data I can dig up -- so we all can become a little more informed, a little more prepared should we have to personally do battle with any one of the 100 possible cancers out there.

The American Cancer Society reports that 1,399,790 new cancer cases will be diagnosed in 2006. This estimate does not include most carcinoma in situ (noninvasive cancer) cases and also does take into account the estimated one million cases of basal and squamous cell skin cancers that will be diagnosed this year. Of these predicted cases, about 564,830 will result in death -- that's more than 1,500 people each day. Cancer is the second most common cause of death in the United States, exceeded only by heart disease, and accounts for one of every four deaths.

These numbers are staggering. But without further explanation, they are broad and all-encompassing and don't say much about how all the individual diseases add up. That's what I plan to do -- break it all down, cancer by cancer, until the numbers make sense. And the cancers do too.