International Physician Update
Uncovering the Secrets of Pancreatic Cancer
 |
|
| Cancer surgeon Charles Yeo, targeting new therapies for pancreas cancer. |
|
|
|
Surgeon Charles Yeo recalls a patient who had a completely asymptomatic cancer of her pancreas. Using conventional screening, no one had been able to detect it. Then she came to Hopkins, where she was intensively re-screened because she had a strong family history of the disease.
Using CT, endoscopic ultrasound and fine needle aspiration, an early malignant lesion was identified and removed.
“Her CT scan was negative and her serum markers were normal—by standard tests, you’d say there was nothing to worry about,” says Yeo. “But we detected it, resected it, cured it.”
That case, Yeo explains, best illustrates the clinical impact of a decade-old Hopkins research group, the Pancreas Cancer Interdisciplinary Working Group. Headed by Yeo, the group has been tapping the talents of oncologists, surgeons, pathologists, gastroenterologists and geneticists, among others, to identify distinct types of pancreatic cancer early, with the aim of targeting therapies to prevent and treat them.
They’ve had some success. A trinity of key genes—p16, p53 and DPC4—has been uncovered, which has helped lead to the identification of certain types of pancreatic cancer and high-risk patient populations.
One type, the medullary variant, has been identified in about 5 percent of patients and has been shown to respond better to certain drug therapies. Another has been linked to Fanconi’s anemia, a rare inherited disease (Cancer Research, May 15, 2003).
“What we think we have is a new genetic cause of some cases, approximately 10 percent or more, of pancreatic cancers,” says oncologist Scott Kern. “The up side is that while these gene mutations cause a horrific disease, they may actually be the Achilles heel of the tumor and make these particular cancers more responsive to treatment.”
“We want to get to the point where every tumor can be well analyzed genetically,” adds Yeo, “so we can target therapeutics on an individual basis.”
The fact that Hopkins operates on more than 150 pancreatic cancer patients each year is moving the group much closer to that goal. Tumor samples are harvested and produced as xenografts in mice models, creating, Yeo says, “a wealth of living pancreatic tumors” to study. Explosive advances in gene expression analysis and proteomics are moving the group forward, too.
“We’ve put the molecular genetics of pancreatic cancer on the map,” Yeo says. “The more we publish, the more people come to us. And that’s made Johns Hopkins a center of excellence for pancreatic and related cancers.”
