Checking for early indicators of pancreatic cancer
Pancreatic cancer is one of the deadliest forms of the disease. In Bermuda it is listed as the fourth most common cancer death. Statistics from the Bermuda Hospitals Board show 6.1 percent of cancer deaths in 2009 were from pancreatic cancer.
The main reason pancreatic cancer takes lives is that it is difficult to recognise. Symptoms often are not apparent until the tumours are at an advanced stage. According to researchers at Johns Hopkins this type of cancer “is generally fatal once the lesions become malignant and symptoms appear. At that point, just 25 percent of those eligible for surgery survive five years, while the rest have a less than five percent chance of surviving five years”.
Statistics are not available for numbers of residents with the disease, but a spokesperson for the cancer care charity PALS said there have been quite a few cases in recent years.
Scientists have also seen higher incidences of pancreatic cancer among diabetics. The Bermuda Diabetes Association estimates that at least 13 percent of Bermudians have type two diabetes, this means that 13 percent are also at risk for pancreatic, breast and colon cancers.
In many instances pancreatic cancer is hereditary. Researchers at Johns Hopkins revealed last week that there is new hope for this group. In the CAPS 3 Study, scientists found that four in ten people considered at high risk for hereditary pancreatic cancer, have small lesions on the organ years before they have any symptoms.
“We now know that although these high-risk patients often tend to develop pancreatic lesions, we can detect the lesions, track them over time and remove them before they become cancer,” said Marcia Canto, professor of gastroenterology and oncology at Johns Hopkins University School of Medicine.
Dr Canto and her team — made up of researchers from Johns Hopkins, Mayo Clinic, Dana Farber Cancer Institute, MD Anderson Cancer Center and the University of California, Los Angeles — studied 216 asymptomatic adults with a strong family history of pancreatic cancer and found that lesions on the pancreas were often a precursor to cancer.
The research also showed that abnormal precancerous lesions were more frequent as people aged.
The team found such lesions in just 14 percent of high-risk subjects under the age of 50, 34 percent of those ages 50 to 59 and 53 percent of those 60 to 69 years old.
It’s important to note that not all pancreatic cysts or lesions become pancreatic cancer.
The study also revealed the best way to detect the pre-cancerous pancreatic lesions is by ultrasound via endoscopy. This method proved better than CT scanning and MRI.
In the study, endoscopic ultrasound detected pancreatic abnormalities in 42.6 percent of participants while CT found them in 11 percent and MRI in 33.3 percent.
Dr Canto noted that an important advantage of endoscopic ultrasound over MRI and CT is that it can also be used to collect cells from the pancreatic lesions, secretions from the pancreas, and fluid from cysts for further study.
The endoscopic procedure entails a doctor passing a thin, lighted tube from a sedated patient’s mouth through the stomach, and into the first part of the small intestine. At the tip of the endoscope is a device that uses sound waves that produce patterns of echoes as they bounce off internal organs. These ultrasonic patterns can help identify tumours that cannot be detected by a CT scan. Using ultrasound to help guide the way, a doctor then inserts a thin needle into the pancreas to remove cells that can be studied later.
Pancreatic cancer screening is not recommended for the general population, Dr Canto said. She explained this is because cysts and other possibly precancerous lesions are far less common in the pancreas than in the colon, because the pancreas is harder to reach than the colon, and because removing lesions requires extensive surgery, often including part of the pancreas. Potential complications are also more likely.
“Early detection is the way to go,” she said. “We need smart screening and individualised treatments based on family history, epidemiology, biomarkers and genetics.”
The study used only people with a strong hereditary risk of developing pancreatic cancer — primarily those with two close blood relatives who have had the disease and those who have inherited genetic markers known to increase the risk of pancreatic cancer, including BRCA2 gene mutation that has also been linked to breast and ovarian cancers.
Bermudian women with BRCA1 and BRCA2 have been sought out by American breast cancer specialist Kevin Hughes to be a part of the Bermuda Cancer Genetic Risk Assessment Programme since 1988.
The findings of the CAPS 3 Study, are published in this month’s issue of ‘The American Journal of Gastroenterology’.