Genetic testing offers new hope
Families of those with disease can find out if they are at greater risk
With pancreatic-cancer patients facing the grimmest of all cancer prognoses, the B.C. Cancer Agency is ramping up research and protocols to provide more hope for such patients and their families.
About 700 B.C. residents are expected to be diagnosed with pancreatic cancer, according to a recent report, but since the cancer is most often detected in the advanced stage and is so difficult to treat, only six per cent survive past five years.
Up to 10 per cent of those diagnosed with pancreatic cancer have an inherited risk for the deadly disease, so in those patients with susceptibility genes identified, healthy (unaffected) family members are now being offered predictive genetic testing once they are referred to the Hereditary Cancer Program.
Dr. Kasmintan Schrader, a medical geneticist at the agency and co-director of the hereditary program, said there are several gene mutations thought to be linked to the development of pancreatic cancer. Some of them, like the BRCA1 and 2 mutations, aren’t specific to pancreatic-cancer risks; they’re also strongly linked to breast and ovarian cancer.
"We have found that if you test all pancreatic-cancer patients, there’s about a five-per-cent chance of identifying one of these high-risk predisposition genes.
“If we test people (family members) who have a higher risk, then that chance goes up to 10 per cent,” she said, referring to the fact that broad screening offers fringe benefits by expanding the pool of those who learn they may be predisposed to various types of cancer. Such individuals can then take prevention or risk-reduction measures, like going for more frequent screenings and imaging tests.
For everyone trying to prevent pancreatic cancer, lifestyle strategies are important — maintaining a healthy weight, exercising, limiting alcohol and not smoking.
Judy Patterson, a 71-year-old Vernon resident, was diagnosed in 2015 with pancreatic cancer, the same type that killed her brother in Chilliwack. Patterson said she provided a saliva sample that looked for about 30 gene mutations and she learned she was a carrier of the ATM gene linked to the cancer. Both her middle-aged sons and other relatives have been tested to determine if they inherited the same gene and they’re awaiting their results.
“All my life I was aware that there was a lot of cancer in my family history, but it was still a shocking diagnosis. I had been having a lot of pain on the left side of my abdomen, which was initially thought to be irritable bowel syndrome. Finally my doctor said I should get a CT scan, but the wait for that at the hospital in Vernon was up to six months, so I paid $1,100 to get it done at a private clinic in Vancouver and boy, am I ever happy I didn’t wait any longer,” she said.
Surgery can sometimes be curative, but Patterson’s tumour was deemed to be inoperable because of where it was.
Patterson’s cancer has recently spread and she’s had more than a year of chemotherapy. Yet she remains optimistic.
She said one of her sons was a bit apprehensive about getting the genetic testing. “But you can’t not want to know if it helps to know,” she said of the way she rationalized it to her son.
Inheriting genetic mutations doesn’t necessarily mean an individual will get pancreatic cancer, a rare cancer. Quantification of risk increases are still being worked out, but this much is known: In those who have a first-degree relative with pancreatic cancer, the lifetime risk goes from about 1.5 per cent to about four per cent.
The gene-testing program is being sponsored through philanthropic funding, largely from the Glotman-Simpson Cypress Challenge, an annual cycling event that was held last weekend in Vancouver. Nearly 700 riders registered for the event — the largest fundraiser for pancreatic research in Canada. This year, $410,000 was raised, bringing the total to just over $2.7 million since it began 10 years ago.
Schrader said none of the testing and research would be happening without private donations.
“This is critical to point out. All pancreatic-cancer patients know they are facing a deadly disease because of the difficult statistics. What we are offering, with these pilot studies and other research, is some hope, and perhaps a silver lining that we identify other family members with the mutations,” she said, noting that when there is a strong family history, individuals can choose to occasionally undergo novel screening techniques like endoscopic ultrasound or MRI imaging.
The cancer agency is also now recruiting patients for a clinical drug trial to test the effectiveness of adding novel immunotherapy drugs to a standard chemotherapy regime. Immunotherapy drugs being used have been helpful for kidney and lung cancers.
Dr. Daniel Renouf, co-director of the Pancreas Centre, is leading the local trial that is underway at several Canadian sites.