Personalized Cancer Therapy on the Horizon
Reported April 20, 2011
(Ivanhoe Newswire) — Cancer survival rates could drastically improve with whole-genome sequencing. A recently published study offers examples of the power that genomic data holds for patients with a cancer diagnosis.
Whole-genome sequencing is a high-tech process that fundamentally maps a person’s DNA and analyzes it for mutations. This has permitted cancer therapies to evolve from a standard therapy for all patients with a given type of cancer to a somewhat more modified and better-suited individualized treatment.
“In patients with breast cancer, colon cancer and gastric cancer, we now have specific approaches for tumors that exhibit certain genetic abnormalities,” Boris Pasche, M.D., deputy director of the University of Alabama at Birmingham Comprehensive Cancer Center, was quoted as saying. “Whole-genome sequencing gives us the ability to screen a much larger number of tumors and correlate them with the outcome of the patient, so it is very likely that our targeted therapy is going to be exploding in the next decade.”
According to the American Cancer Society, half of all men and one-third of all women in the United States will develop cancer during their lifetimes, and few, if any, do not know someone who has had cancer or died because of it. This new-fangled advance could alter those chances.
“In one study, a patient with leukemia had a poor prognosis, but through sequencing, this patient was found to have a gene that showed they would react favorably with a different therapy than originally recommended,” Pasche said. “If patients have certain genes, they may not respond to certain treatments. But whole-genome sequencing gives a full picture of the genetic make-up of the tumor and the patient, and it may allow the physician to target a new treatment.”
Pasche adds that the impartial picture of the sequenced DNA allows physicians to look at tumors in a way not achievable beforehand. Even when the technology ultimately was accessible, it was far too costly. Currently, the price to sequence a patient’s complete genome and the genome of their tumor as well is down by more than 100 fold; however, it still ranges from $30,000 to $40,000.
“Prices are still dropping very rapidly; in the next 10 years, it will cost less than $10,000, and it certainly will be more affordable in the next five years,” says Pasche, who believes having sequencing covered by insurance or otherwise is ultimately a work in progress.
At UAB, Pasche says whole-genome sequencing is being implemented in myriad projects, most markedly in a clinical trial for women with triple-negative breast cancer.
“There is a high degree of expectation with whole-genome sequencing,” he concludes. “The hope is that it will help survival rates of those with cancer.”
SOURCE: JAMA, April 20, 2011
