The pancreas is a part of the digestive system, responsible for producing important enzymes and hormones that break down foods.
The study, published in the American Cancer Society's (ACS) peer-reviewed journal CANCER, examines one of the most stealthy cancers; the majority of cases are only discovered at a late stage that is not amenable to surgical intervention.
Only 10-20% of pancreatic cancer patients undergo resection surgery, and of these patients, approximately 80% still die from the disease. The 5-year survival rate for pancreatic cancer is currently less than 5%.
However, according to the study's authors, recent research has suggested that there is a period of 10-20 years from the original cancer-initiating mutation to the establishment of the disease in an advanced form. This gap represents a possible opportunity for intervention, so long as the cancer is detected.
Although pancreatic cancer only accounts for 3% of cancer cases in the US, the ACS estimate that approximately 46,420 people (23,530 men and 22,890 women) will be diagnosed with pancreatic cancer in 2014. Over the past decade, rates of pancreatic cancer have been rising slightly.
A hereditary disposition
Experts have previously found that some cases of pancreatic cancer appear to run within family groups, though despite this, it is largely unknown specifically which genes are responsible for a hereditary disposition toward the disease.
Dr. Andrew Biankin of the University of Glasgow, Scotland, and colleagues analyzed 766 patients who had been diagnosed with pancreatic cancer. Patients were defined by the authors as having an inherited disposition toward the disease if they had one or more first-degree relatives with pancreatic cancer. If not, their cases were defined as sporadic.
Of the 766 patients, around 9% had first-degree relatives with pancreatic cancer. The researchers found that these patients with familial pancreatic cancer tended to have more pre-cancerous tissue in the area adjacent to their cancer than those with sporadic pancreatic cancer.
Dr. Biankin and his team also discovered that members of the families affected by pancreatic cancer were at a higher risk of developing other forms of cancer, such as endometrial cancer and melanoma. Patients with familial pancreatic cancer were more than twice as likely to have family members with other forms of cancer (extrapancreatic malignancy) than those with sporadic cancer.
In cases of both familial and sporadic pancreatic cancer, an association was found between active smoking and a significantly younger age at diagnosis.
Likely that inherited genes play 'a significant role'
"These findings are important because they suggest that the genes we inherit from our parents likely play a significant role in our lifetime risk of developing pancreatic cancer," says Dr. Biankin. He continues:
"Secondly, they emphasize that when assessing someone's individual risk of developing pancreatic cancer, it may be important to assess not just family history of pancreatic cancer but other malignancies too. Finally, our data emphasize the importance of smoking abstinence."
The authors conclude that, in order to identify susceptibility genes, strong clinical characterization of familial pancreatic cases will be essential.
They acknowledge that the study has some limitations. The authors were unable to adjust their rates of extrapancreatic malignancy in the family members of patients for family size. Information regarding first-degree relatives was also obtained from the patients, leaving the study open to recall bias.
There is still some distance to go before health care providers can detect this cancer early with ease. As the organ lies deep within the body, early tumors cannot be detected by physical examination and symptoms do not typically manifest until the cancer has spread elsewhere.
As a result, testing people who could be at an increased risk of the disease is a helpful way of potentially catching pancreatic cancer early. Identifying precisely what makes people more susceptible to the disease is the first part of this battle.
Last month, Medical News Today reported on a study published in the journal Nature Medicine, detailing a newly discovered marker that could lead to the early detection of pancreatic cancer.