Possibility of Personalized Treatment Regimes for Cancer Patients
By Layla HoodPublished May 1, 2013Researchers at the University of Washington celebrated the remission of a colleague’s Leukemia last July. Leukemia is a cancer of the blood cells, caused by mutations in cell reproduction. In an attempt to determine what was wrong with the young doctor, researchers at the university sequenced the genomes of both his cancer cells and his healthy cells. They were then able to compare the genome sequences of the two types of cells in order to determine the specific cause of the leukemia. The knowledge of the specific genome mutation allowed the research team to identify the most effective course of treatment, resulting in remission of the doctor’s ailment.
The National Cancer Institute reported that 1 in 74 men and women will be diagnosed with Leukemia in their lifetime. Of those diagnosed, about half will die. The recent advancements in genome sequencing introduce the possibility of personalized treatment methods. The ability to sequence entire genomes allows for determination of the root cause of cancers, and therefore the most effective method for treatment. Most physicians currently classify and treat Leukemia, as well as other cancers, based on level of progression and location in the body. Surely, all people with acute lymphocytic leukemia do not respond to available treatments. If they did, survival rates would be dramatically higher. People suffer from mutations at different locations within their genomic sequence, so tailoring treatment methods to specific cases will make the future of leukemia treatment more effective and efficient.
Scientists at the Genome Institute found that even as cancers evolve they maintain the original cancer-causing mutations. Researchers predict that drugs targeting the founding cancer-causing mutations will result in positive responses to treatment, increasing the likelihood of remission. In order to achieve this, the genomic sequence in its entirety must be evaluated. A single human chromosome is estimated to contain 6 billion base pairs and may take several hours or days to sequence entirely, depending on the availability of technology. Sequencing machines with these capabilities cost about $149,000 per machine and an additional $1,000 per sequencing, a huge drop from the $10 million cost just 5 years ago. The drop in cost has resulted in a small increase in whole genome sequencing to determine the causes of cancer, improving the course of treatment.
The barrier for many patients to utilize genomic sequencing will be that insurance may not cover the cost of sequencing and necessary treatments. Although it may become more common for whole genome sequencing to occur, many patients cannot afford it out of pocket. Furthermore, insurance companies often shy away from more expensive treatment methods if cheaper, albeit less effective, treatment methods are available. For example, the young doctor from the University of Washington who suffered from leukemia could not afford the medicine which ultimately caused his leukemia to go into remission—a treatment that was only considered following a whole genome sequence. 7 ½ months of the drug he needed would have cost more than 7 times his annual salary. After a compassionate donation of the expensive drug, his blood work shows no cancerous cells.
As whole genome sequencing becomes cheaper and more accessible to doctors to diagnose the cause of leukemia and other cancers, insurance companies must consider paying the initial higher cost for more effective and efficient sequencing. Although alternate methods may be available and less expensive, doctors will be able to more effectively identify the correct treatment using genomic sequencing. Additionally, as doctors become better at prescribing the most effective treatment methods, the possibility for remission may increase and patients will become healthier, potentially saving insurance companies and America more money in the long run. Insurance companies should strive to make these live-saving treatments more accessible to ailing cancer patients.