Doctors have long wondered why two women with the "same" type of breast cancer could have wildly different prognoses when following the same treatment plans. A new, multinational research study may illustrate why that is as well as providing scientists with new directions to take future research studies in. That research, published in the journal, Nature, highlights the fact that current information may only hold a very small piece of the breast cancer puzzle.

Researchers from Canada, Britain and other nations reviewed genetic material, including both RNA and DNA from more than two thousand different breast cancer tumors and found that while modern science has classified four to five different subtypes of breast cancer, the number is likely to be much higher that that, possibly as much as twice as high. That may mean that many of the treatment plans that are being used today may be ineffective at best and potentially toxic at worse.

Members of the research collective came up with two potential uses for this research that will serve as the road map for future studies. The first, will be to come up with a way to use these new subtypes to determine if a current treatment type would be helpful or not in treating it. The second would be to find new drugs and other alternative treatment tandems that could address the gene variants.

Doctors and patients have long been frustrated by the difference in outcomes with seemingly similar types of breast cancer. Patients who have been diagnosed with one type of estrogen receptor positive breast cancer have fairly positive outcomes with more than seventy percent still alive at the fifteen year mark while women who have been diagnosed with a secondary type of a similar breast cancer has a less than thirty percent chance of that rate of survival even with similar treatment plans in place for both.

There are other factors that determine how well a cancer will respond to treatment, regardless of the type of cancer or the type of treatment including prior health history, age at detection, family history and of course, what stage the cancer was in when found. Researchers want to continue finding the best type of treatment plans for each of the many subtypes of breast cancer but warn that there will never be a single, best case treatment or outcome for everybody because of all of the individual factors that are involved.