SATURDAY, May 31 (HealthDay News) -- Patients diagnosed with pancreatic cancer -- which historically carries a grim prognosis -- nearly doubled their overall survival when the cancer drug Gemzar was used after surgery, new research shows.

Unfortunately, only about 15 percent of pancreatic cancer patients are even candidates for surgery.

"Pancreatic cancer is probably the deadliest cancer that we face," said Dr. Richard Schilsky, president-elect of the American Society of Clinical Oncology (ASCO) and a professor of medicine at the University of Chicago. "It's frequently not even diagnosed until it's very far advanced, when treatments are not very effective."

Schilsky spoke at a teleconference earlier this month; the results of the new trial, a follow-up from data first presented in 2005, were released Saturday at ASCO's annual meeting in Chicago.

Gemzar (gemcitabine) is the standard treatment for pancreatic cancer that can't be removed surgically.

At three years, 23.5 percent of participants taking Gemzar had survived without a recurrence, versus 7.5 percent in the placebo group; that number dropped to 16.5 percent at five years, versus 5.5 percent in the control arm.

Overall, 36.5 percent of Gemzar patients were still alive at the five-year mark (vs. 19.5 percent in the placebo group) and 21 percent were still alive after five years (vs. 9 percent in placebo).

"Treatment with gemcitabine as compared to observational in patients with resected [surgically removed] pancreatic cancer resulted in improvements in disease-free survival and overall survival," said study co-author Dr. Helmut Oettle, of Charite University Medical School in Berlin. "Adjuvant treatment [with Gemzar] doubled long-term survival rate after five years compared with the observation group. Gemcitabine should be the standard of care for adjuvant treatment of pancreatic patients."

"This represents a very substantial improvement in outcome for these individuals, and I think we can look forward to seeing widespread adoption of gemcitabine for patients with pancreatic cancer that can be surgically removed," Schilsky said.

Researchers at the ASCO meeting also reported progress with another tough-to-treat cancer, advanced kidney cancer.

While there have been significant advances in recent years with drugs such as Sutent (sunitinib), that success has brought a new challenge: How to treat patients who don't respond to the latest generation of new therapies.

Enter everolimus, a drug which interferes with blood supply to the tumor and which is one of the first in a relatively new class of compounds. Patients randomized to receive everolimus plus best existing therapy had a 70 percent reduction in the risk of recurrence or death, compared to patients who received best existing therapy alone. For patients on everolimus, it took about four months for the cancer to return, versus about two months in the placebo group.

"While that may not sound like an enormous leap forward, it's actually a very important observation for several reasons," Schilsky explained. "This drug is targeting a different molecular pathway compared to anti-angiogenesis drugs [those that block blood supply to the tumor], so it's working in a completely different way. Secondly, when we make these observations, not only do patients benefit from a delay in progression of their cancer, but this kind of observation always gives us a new lead and an interest in moving these drugs up earlier into cancer treatment."

"A setting of unmet clinical need that has now been filled," added study author Dr. Robert Motzer, an attending physician at Memorial Sloan-Kettering Cancer Center in New York City. "Everolimus should be the standard of care in this setting, pending approval by regulatory authorities."

More information

The National Cancer Institute has more on pancreatic cancer.