Vaccination of Patients With Breast Cancer With Dendritic Cell/Tumor Fusions and IL-12

TUMOR COLLECTION: Tumor cells will be collected from the participant to make the study vaccine. Based on the location of the tumor, a decision will be made as to the best approach to obtain these cells. DENDRITIC CELL COLLECTION: Participants will undergo a procedure known as leukapheresis to obtain their dendritic cells (this procedure may be done before or after the tumor cells have been obtained). This procedure takes about 2-4 hours. If not enough cells are collected, the participant may be asked to return for an additional leukapheresis procedure. If sufficient number of cells are obtained, tumor cells and dendritic cells will then be fused (combined together to make one larger cell) together in the laboratory and divided into the appropriate dose for administration. TREATMENT: Treatment will consist of an injection of tumor cells fused with dendritic cells under the skin every 3 weeks for a total of 9 weeks. The dose that the participant receives will depend on the total number of fusion cells that are made. STUDY COHORTS: The first group of three participants will receive the DC/Tumor Fusion study vaccine alone. The next group of 3 participants will receive the DC/Tumor Fusion study vaccine with a low dose of Il-12. If there are no significant side effects the following groups of subjects will be treated with the DC/Tumor Fusion study vaccine and a higher dose of Il-12. PATIENT MONITORING: Participants will be carefully monitored during the study period and the following tests and procedures will be performed: physical exams (weekly); blood collections (weekly); DC/Tumor Fusion study vaccine Journal (for the participant to record any side effects or other medications they may be taking); tumor cells skin test (before the first vaccine and one month following the last vaccine); skin biopsy at the site of the vaccination administration, accessible tumor site, or if there is a local reaction site.