Patients who have had a recent diagnosis of diabetes mellitus (DM) and have undergone a surgical resection for pancreatic ductal adenocarcinoma may have poorer survival outcomes than those without diabetes, or those with longstanding DM, according to a recent study.
The prospective observational study looked at 296 patients. Of that group, 140 had DM—26 with longstanding disease, 99 with recent-onset DM, and 15 whose diagnosis date was unknown.
Longstanding DM and postoperative DM diagnoses had no impact on prognosis after surgery, according to the study, but there was a difference seen with patients who had recent-onset DM (2 to 4 years before the cancer diagnosis).
Disease-free survival was 1.14 years in the recent-onset group, compared with 1.3 years in the diabetes-free group, and overall survival (OS) was 1.52 years versus 1.87 years.
“Compared to cases without DM, patients with recent onset DM were more likely to have residual disease after surgery and develop liver metastases during follow-up,” the authors wrote.
Recent DM diagnoses were also independently associated with pancreatic cancer relapse, according to the study, though researchers are still unclear why.
“The data suggest that the association of diabetes with survival of patients is more complex than previously hypothesized,” study author Lorenzo Piemonti, MD, Deputy Director Diabetes Research Institute (DRI) at San Raffaele Scientific Institute in Milan, Italy, said in an interview, noting that there may be a number of explanations behind the results.
“We can speculate that the loss of pancreatic parenchyma leading to the diabetes onset may be the consequence of a more aggressive cancer or of a tumor with longer duration before diagnosis,” he said. “Another possibility could be that under recent-onset hyperglycemic conditions, an increased level of oxidative stress and pro-inflammatory factors cause pancreatic nerve damage and an inflammatory response, which simultaneously facilitates cancer cell proliferation, migration, and metastasis.”
Further research explaining the correlation between pancreatic cancer and diabetes is particularly important, noted Piemonti as pancreatic ductal adenocarcinoma is one of the most lethal forms of human cancer and is growing in incidence.
The success of finding patients who are at increased risk of asymptomatic pancreatic diseases will largely depend on the ability to identify biomarkers, especially as primary diabetes is common and pancreatic diseases are far less common.
“Identification of a specific diabetes signature associated to pancreatic ductal carcinoma could be a key to detect asymptomatic, early stage tumors,” Piemonti said. “Epidemiological studies indicate that about half of all patients with pancreatic cancer have diabetes at the time of cancer diagnosis.”
While advances have been made in the field of chemotherapy to treat pancreatic cancer, surgery still remains the only treatment that gives potential for being cured.
In the meantime, there are some things that patients can do that may improve their outcomes, such as maintain a healthy weight and diet.
“Poor nutritional status has been reported to be associated with worse survival,” Piemonti said. “The adequate treatment of diabetes must be pursued to improve the chance to fight against this tumor.”
Balzano G, Dugnani E, Gandolfi A, et al. Effect of diabetes on survival after resection of pancreatic adenocarcinoma. a prospective, observational study. PLoS One. 2016;11(11):e0166008.