Dendritic Cell Vaccines Against Her2/Her3 and Pembrolizumab for the Treatment of Brain Metastasis From Triple Negative Breast Cancer or HER2+ Breast Cancer

Inclusion Criteria: * female participant is eligible to participate if she is not pregnant,not breastfeeding, and at least one of the following conditions applies: * Not a woman of childbearing potential (WOCBP) * A WOCBP who agrees to follow contraceptive guidance * WOCBP must agree to use acceptable birth control methods for the duration of the study and until persistence of the study drug is no longer detected in the peripheral blood:this may be a period of several years. Methods for acceptable birth control include: condoms, diaphragm or cervical cap with spermicide, intrauterine device, and hormonal contraception; it is recommended that a combination of two methods be used. NOTE: If the risk of conception exists, patients must agree to use highly effective contraception throughout the study and for at least two years following the last study treatment administration * Negative serum and highly sensitive urine pregnancy test(s): i) within 72 hours prior to study allocation; ii) following initiation of treatment, pregnancy testing will be performed for WOCBP and interpreted prior to every cycle of pembrolizumab (Initial Treatment Phase); iii) at the End of Treatment (EOT) Assessment; and iv) whenever pregnancy is otherwise suspected. Note: In the event that 72 hours have elapsed between the screening pregnancy test and the first dose of study treatment, another pregnancy test must be performed and must be negative in order for subject to start receiving study medi…