October 29, 2010
Pancreatic Cancer : Not So Aggressive
(Ivanhoe Newswire) -- Pancreatic cancer only has 4.6 survival rate, mostly due to not being able to catch it in its early stages. Scientists have discovered that pancreatic cancer develops and spreads more slowly than was previously thought, and therefore allows a longer window of opportunity to catch it and stop it.
"For the first time, we have a quantifiable estimate of the development of pancreatic cancer, and when it would be best to intervene," Christine Iacobuzio-Donahue, M.D., Ph.D., associate professor of pathology and oncology at Hopkins' Sol Goldman Pancreatic Cancer Research Center was quoted as saying "so there is potentially a very broad window for screening." Right now, however, she adds, "pretty much everybody is diagnosed after that window has closed."
Pancreatic cancer is notorious for not being able to catch in its early stages because there aren't noticeable symptoms or imaging machines specific for cancer.
After the first cancer cell appears, it takes an average of seven years for that cell to turn into the billions that make up a cancerous tumor the size of a plum. At this point, at least one of the cells within the tumor has the potential and ability to spread to other organs. Patients typically die, on average, two and a half years after the cancer metastasizes.
This contradicts the previous idea that pancreatic cancers metastasize very early in their development.
For the study, scientists collected tissue samples during autopsies of seven patients who died from pancreatic cancer that had metastasized to other organs. The tissue samples were taken within six hours after each patient's death, so the scientists were able to keep some of the cells alive long enough to extract DNA from them. They then sequenced the series of chemical "letters" that form genes.
The scientists used mathematical models to simulate the timing of pancreatic cancer progression. They conservatively estimated an average of 11.7 years before the first cancer cell develops within a high-grade pancreatic lesion, then an average of 6.8 years as the cancer grows and at least one cell has the potential to spread, and an average of 2.7 years from then until the patient's death.
The Hopkins scientists say the goal is to develop a pancreatic cancer screening methods similar to the protocol used from breast and colon cancer. Since the early stages of pancreatic cancer show no symptoms, Iacobuzio-Donahue says, perhaps at a certain age people should undergo an endoscopy to screen for pancreatic cancer.
SOURCE: Nature, published online October 27, 2010