Vaccine aims to prevent breast cancer recurrence: preliminary results.(Gynecology)

CHICAGO -- A vaccine so simple it could potentially be administered by community physicians induced a durable and specific immune response in a small group of breast cancer patients at high risk of recurrence.

No patient who had a durable response to the vaccine experienced a recurrence of breast cancer over a median follow-up of 18 months, Lt. Col. George E. Peoples Jr. said during a press briefing at the annual clinical congress of the American College of Surgeons.

In all, 34 women previously treated for aggressive breast cancer were enrolled in the government-sponsored study. Because the patients had evidence of involvement in multiple lymph nodes, an expected rate of recurrence in the group would be 20%-25% within 2 years despite the fact that they received extensive therapy, including surgery, hormone therapy, radiation treatment and/or chemotherapy, said Dr. Peoples of Walter Reed Army Medical Center, Washington.

Twenty of the women are being followed as controls in the trial, and four of them have experienced recurrences of their cancer.

The 14 women whose tumors ex pressed the E75 peptide on surfaces of the HER2/neu protein were given a vaccine aimed at that specific target antigen plus granulocyte-macrophage colony-stimulating factor (GM-CSF) intended to trigger a generalized immune response.

Two of the 14 experienced recurrences. These two patients had the weakest immune responses to the vaccine, and their immune responses were transient.

Side effects associated with the vaccine were relatively mild and included fatigue, flulike symptoms, and lightheadedness in several patients.