An experimental pancreatic cancer vaccine seems to be nudging survival rates higher for this aggressive, often-fatal malignancy for which there are few treatment options.

Use of the vaccine improves the 2-year survival of patients who have surgery to remove the tumor from about 42 percent to 76 percent, according to the results of a phase II trial presented Tuesday at a cancer meeting in Philadelphia.

Still, the authors emphasize that the findings are preliminary and further follow-up is needed.

The vaccine, which has shown encouraging results in an initial phase I trial, is designed to boost the patient’s immune responses to pancreatic cancer cells that may be left behind after surgery and chemotherapy and radiation.

In the phase II trial, the vaccine, which was given to 60 patients with resected pancreatic cancer, was associated with 1- and 2-year survival rates of 88 percent and 76 percent, respectively. Previous studies have typically yielded corresponding survival rates of 63 percent and 42 percent.

In comments to Reuters Health, study investigator Dr. Daniel Laheru, from Johns Hopkins Kimmel Cancer Center in Baltimore cautioned that while the findings are potentially good news for patients with early stage disease, “only about 15 percent to 20 percent” of patients with the malignancy fit into this category.

“Clearly, the majority of patients have advanced disease at presentation,” he said. He also said   that his group completed a study last year using a similar vaccine in patients with advanced pancreatic cancer and “we’ve just submitted the results for publication.”