Pancreatic cancer cells.
Image: Steve Gschmeissner Photo Researchers, Inc.
-
The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
Read More »
A patient who receives a diagnosis of pancreatic cancer has only a 5 percent chance of surviving for five years, a harrowing prognosis that scientists have long struggled to understand. Part of the problem, new research suggests, is that the disease is not typically diagnosed until 15 years after the first cancer-causing mutations appear, by which point the cancer has spread and become highly aggressive. The findings indicate that there may be plenty of time for doctors to intervene before pancreatic cancer becomes lethal—an exciting prospect given recent advances in diagnosing the disease early, when it can be successfully removed with surgery and chemotherapy.
In research published recently in Nature (Scientific American is part of Nature Publishing Group), scientists at Johns Hopkins University sequenced the genomes of seven people who had died of late-stage pancreatic cancer. Their tumor cells contained different types of mutations that the scientists traced back in evolutionary time using mathematical models to build a kind of “family mutational tree.” The models suggested that cancer cells appear 10 years after the first cancer-causing mutation arises and that another five years pass before the cancer cells spread and become deadly. The findings question “the pervasive belief that pancreatic cancer is so aggressive and grows so quickly that screening cannot be effectively used,” says study co-author and Johns Hopkins pathologist and oncologist Christine A. Iacobuzio-Donahue.
In the past two years scientists have brought screening techniques for pancreatic cancer closer to reality. In February 2010 researchers at the University of California, Los Angeles, compared RNA found in the saliva of 60 treatable pancreatic cancer patients with the saliva of 30 cancer-free individuals and identified four RNAs that together could correctly identify the cancer 90 percent of the time. And in March 2009 Northwestern University researchers publishing in the journal Disease Markers developed an optical technology that recognizes various stages of pancreatic cancer cells with 95 percent sensitivity. The technique uses light scattering to detect changes in the cells of the duodenum, part of the small intestine adjacent to the pancreas, which can be viewed using minimally invasive endoscopy.
These technologies are not yet available commercially, but early detection using optical tests and blood or saliva analyses should “advance measurably in the next decade,” says David Tuveson, an oncologist at the Cambridge Research Institute in England. Until then, he notes, doctors should consider using current techniques such as CT and MRI scans to screen patients who are at high risk because of family history of the disease. “Recall that our Supreme Court Justice Ruth Bader Ginsburg had a small pancreatic cancer diagnosed in January 2009 when she was undergoing a CT scan,” Tuveson says. One month later doctors removed it successfully and discharged her with a clean bill of health.
This article was originally published with the title How Old Is Your Cancer?.
Already a Digital subscriber? Sign-in Now
If your institution has site license access, enter here.
See what we're tweeting about
10 Comments
Add CommentBetter diagnostic methods could allow us to treat cancer sooner enough without actually requiring better treatment methods. Still, cancer is so difficult to treat because you're basically fighting evolution on a very fast scale. If you find one treatment that works for most cancer cells in a tumor there will often be a few cells in the tumor that evolve a countermeasure to it. I don't think we'll actually cure cancer until we're able to make it impossible for cancer cells to divide by making a fundamental change to them, like the WILT strategy (Whole-body Interdiction of Lengthening of Telomeres) proposes to do.
Reply | Report Abuse | Link to thisI agree with the response of openeyes999, because surgical removal of cancer cells, does not guarantee the removal of all cancer cells. Therefore, it is rather wise for us to develop a technique to mutate the genes, perhaps by revising our current chemotherapeutic diagnosis.
Reply | Report Abuse | Link to thisPancreatic Cancers, like that of Breast, Colon, and other forms of Cancers, have been the number one killer of so many people in the world today. Advancements in technologies are creating better diagnostic tools that making it easier to understand and cure many of these illnesses of humankind, but there is one question that does not seem to be raised by the medical community; why are these mutations arising in the human biology in the first place? Why are these lethal mutations occurring in the first place. Even if we do find a "cure" for these cancers, it does not stop them from taking root in the first place. And, what role will these mutations have on the future evolution of the human species? What role does mutations play in the evolution of a species? Are mutations just one of the outward symptom of the disease, rather than the disease itself?
Reply | Report Abuse | Link to thisMy sister and my father both died from Cancer, but my mother and myself are cancer free. If cancer cancer is hereditary, why did my sister and father die from it and we are cancer free?
The epigenome, which regulates how genes may be expressed, is probably a factor. It causes identical twins to have different genetic outcomes in some cases. See the PBS Nova segment:
Reply | Report Abuse | Link to thishttp://www.pbs.org/wgbh/nova/genes/
Recently read somewhere that cancer has been found in some pretty old human remains. It's been with us a long time, possibly a few thousand years.
Reply | Report Abuse | Link to thisNatural selection would have little interest in a disease that mostly occurs in older adults. Only one thing counts toward selection and that is whether you reproduce. The prime age for that in humans is around 15 - 25.
If you have had no children, or are past the age when it is likely, evolution loses all interest in you.
An innovative <a title="Brand new cancer blood test might revolutionize prognosis and remedy" href="http://personalmoneystore.com/moneyblog/2011/01/04/new-cancer-blood-test/"> blood test to detect cancer cells</a> could eventually replace conventional methods. The brand new cancer blood test might make early diagnosis of cancer easier. Testing a patient's blood using the brand new technique could result in more effective remedy and help determine if the cancer has been defeated.
Reply | Report Abuse | Link to thisApparently cancer's been with human race for a long time. I do doubt that surgical removal of the tumors can actually make them completely disappear. We all hope that one day cancer is completely eradicated.
Reply | Report Abuse | Link to this@kristi276, i agree with euler21, probably epigenetic factors.
Reply | Report Abuse | Link to thisthis is such a good article to read (:
diagnosed with chronic idiopathic pancreatitis and having a family history of pancreatic cancer, the 10 year wait for available screening technology will be too late for me I fear.
Reply | Report Abuse | Link to thiskristi276,
Reply | Report Abuse | Link to thisYour mother could not have inherited cancer from your father. She's safe enough. Your sister probably inherited it from your father. You may be cancer-free by not having inherited those genes that caused the susceptibility from your father (you inherit only half his genes).
Hereditary causes are probabilistic, not deterministic. May you be safe, and your children, too.