- Pregnant or lactating women. Pregnant women are excluded from this study. Women of childbearing potential must have a negative pregnancy test per standard of care prior to the surgery for tumor removal. A second pregnancy test must be performed 7 days prior to the first vaccination and must be negative. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother, breastfeeding should be discontinued if the mother is treated on study.