There is an interesting result from the cancer research community today, which could be a major breakthrough in treatment methods (although it is admittedly very unscientific).

An oncology researcher in the U.S. had been diagnosed with leukemia several years back, and had undergone several rounds of chemotherapy. Unfortunately each time his cancer would go into remission and then return again later. The latest rounds of treatment were not having any significant effect at all.

So his fellow researchers decided to try a simple experiment. They took two DNA samples from the patient, and sequenced all of the genes in both healthy tissue and in the cancer cells. (As an indication of the scale of this project, when I was an undergraduate science student fifteen years ago the human genome project required thousands of staff members and millions of dollars to do such a sequencing. With modern technology though, it can be done by a single large medical lab for only a few thousand dollars)

What the researchers discovered was that the cancer cell DNA contained one defective gene that was allowing it to reproduce quickly. This gene would be a like a signature of the cancer cells and not the healthy cells nearby. Even more amazing for this team was that the defective gene was identical to one that had been identified in kidney cancers, but not in leukemia before now. Based on this discovery, the patient was given a medication used in kidney cancers that blocks the production of new cancer cells, and for the present at least it has put the patient's leukemia into remission.

Now the research team are examining DNA from other leukemia samples to determine if this patient was unique or if such treatments would work for all patients. 

Of course this result is not scientific, and must be taken with some healthy skepticism. It was a single patient who may be uncommon. The cancer could have gone into remission on its own, or another substance could have aided the treatment, or any number of other causes. We also do not know if the patient is permanently cured, only temporarily cured, or if the drug has just caused a suppression of the cancer and not really cured it. All of these things will have to be studied before it can truly be considered a breakthrough.

However it is an interesting result. There may come a day when oncologists simply place a biopsy sample in a machine that analyzes the DNA and prints out the specific type of gene defect. Instead of chemotherapy or radiation therapy that attacks everything, new treatments could be developed to only attack cells carrying this defective gene. Maybe one day in the foreseeable future cancer will be a minor annoyance and not a life altering event. 
Indeed, routine DNA sequencing is a scary prospect for many reasons, but in this case it could soon become a life saving tool of doctors and hospitals everywhere.