Innovative vaccine could offer hope to patients with advanced ovarian cancer

Jul 10 2013

Loyola University Medical Center is conducting a clinical trial of an innovative vaccine that could offer hope to patients with advanced ovarian cancer.

The vaccine, derived from the patient's tumor cancer cells, is designed to jumpstart the patient's immune system to attack and kill cancer cells.

Ovarian cancer is the fifth leading cause of cancer-related deaths in American women, causing more than 15,000 deaths per year. In about two-thirds of patients, the cancer has spread beyond the ovaries to other parts of the body by the time it is diagnosed. Current treatment is to surgically remove as much of the tumor as possible, followed by chemotherapy. But despite improvements in surgical techniques and chemotherapy, most patients with advanced ovarian cancer relapse at some point. The five-year survival rate for patients with advanced ovarian cancer is less than 30 percent. There is no cure for patients with relapsed or metastatic ovarian cancer who have failed first-line treatment.

In the vaccine trial, Loyola is enrolling patients who have advanced ovarian cancer. Following surgery, tumor cells are dissolved in a solution called lysate that contains fragments of the cancer cells. The lysate is joined with some of the patient's immune system cells to create the vaccine. (The immune system cells used in the vaccine, called dendritic cells, are taken from the patient's bloodstream.)

A dendritic cell is a type of white blood cell, sometimes called a "presenting cell." A dendritic cell primes the immune system by presenting fragments of a tumor cell to the immune system's killer cells. In effect, the dendritic cells educate killer cells to attack and kill cancer cells.

A patient receives as many as nine vaccine shots, spaced two weeks apart. The vaccine is injected into lymph nodes in the pelvis.

Ovarian cancer appears more likely to respond to such immune system therapy than other solid-tumor cancers such as breast, lung and kidney cancers, said Dr. Patrick Stiff, principal investigator of the vaccine trial and director of Loyola's Cardinal Bernardin Cancer Center.

Colleen Olund, 62, of La Porte, Ind. had relapsed twice from ovarian cancer before receiving the experimental vaccine. After her first round of chemotherapy, she was in remission for three and a half years. But after a second round of chemotherapy, her remission lasted only three months.

Shorter and shorter remissions are typical in ovarian cancer. But after Olund received the ovarian vaccine, the cycle was reversed - the cancer was in retreat a full 10 months. Moreover, the vaccine did not have the toxic side effects of chemotherapy. Olund felt a bit nauseous after a few of the injections. "But compared to chemotherapy, the vaccine was a walk in the park," she said.

Although the cancer has begun to creep back, Olund continues to feel good and work full time running a non-profit housing development corporation and a public housing authority.

"The vaccine has been a very successful treatment for me," she said.

Stiff agrees. "To see such a significant remission is unusual for any type of therapy for ovarian cancer, especially a therapy that is non-toxic," he said.

Further refinements of the vaccine could make it more effective. The vaccine also might be more effective if patients received booster shots, or if the vaccine were given earlier in the disease, Stiff said.

"We definitely think we are on the right track," Stiff said.

Source: Loyola University Medical Center