These data will be tabulated according to the affected body system. Descriptive statistics will be used to summarize changes from baseline. The second objective will be achieved by evaluating the immune response to HER2 in a quantitative fashion based on experimental data obtained using methods described in section 12. A significant immune response in an individual patient will be defined as either the development of, in patients with no measurable precursors at baseline, precursor frequencies > 1:20,000 as measured by CFC; or as a 2- fold increase in baseline precursor frequency in those patients who have a pre existent immune response. The number of patients who achieve a significant immune response after vaccination will be used to assess the immunogenicity of the vaccine. Fourteen or more patients out of 20 would need to be successfully immunized for the vaccine to be considered immunog enic. This criterion is based on our hypothesized immunization rate of at leas t 70% against the HER2 antigen , which would justify conducting a Phase II study, designed to evaluate the ability of the immune response to protect against recurrence of HER2 overexpressing tumor. Table 4 shows the probability of observing 14 or more successes among 20 subjects for several true rates of success. 6304p Protocol 118 04/06/2016 Table 4. Probability of observing at least 14 successes in 20 patients True rate of success Pr (≥14 successes) 50% 0.06 60% 0.25 70% 0.61 80% 0.91 90% 1.0 Regarding secondary objective, OS in the Stage IV breast cancer patients will be compared to the rate in a cohort of historical controls. This study was not designed to be sufficiently powered for any particular hypothesis testing, since time -to-event analyses generally require larger sample sizes than simple two- way comparisons.