Systemic Anti-Cancer Therapy Dose Modifications for Individuals With Duffy Null Phenotype

This research study is a parallel arm, pragmatic, pilot study. As a pilot study it will be the first time investigators are examining using Duffy null specific dose modification guidelines for treatment dosing for participants with multiple myeloma or triple negative breast cancer receiving treatment of: * Daratumumab, lenalidomide, bortezomib and dexamethasone for multiple myeloma * Paclitaxel, carboplatin, doxorubicin, cyclophosphamide, and pembrolizumab for triple negative breast cancer The study will also be looking to understand health experiences of participants with and without the Duffy null phenotype through optional observational and survey studies. The U.S. Food and Drug Administration (FDA) has approved daratumumab, lenalidomide, bortezomib and dexamethasone as a treatment option for some individuals with multiple myeloma. This study uses these drugs in ways typically used in clinical practice but not in ways approved by the FDA. Specifically, the FDA approval does not approve the use of this treatment for more than 4 cycles prior to stem cell transplantation or in those who are deferring or ineligible for transplantation, or with the specific drug dosing used in this study. These unapproved modifications, however, are supported by treatment guidelines from the National Comprehensive Cancer Network. The U.S. Food and Drug Administration (FDA) has approved paclitaxel, carboplatin, doxorubicin, cyclophosphamide, and pembrolizumab for preoperative treatment of triple negative breast cancer. This study uses these drugs in ways typically used in clinical practice but not in ways approved by the FDA. Specifically, the FDA approval does not approve the use of this treatment in individuals who have 1-10% ER or PR positivity (called low-level positivity). This population, however, is often treated as having ER or PR negative disease, and this treatment decision is noted as acceptable by the National Comprehensive Cancer Network. The research study procedures include screening for eligibility, clinical exams-medical history/physical exam, study treatment, and surveys. The study treatment for the multiple myeloma group will be Bortezomib, Daratumumab, Lenalidomide, and Dexamethasone given over a 28 day cycle for 6 cycles. The study treatment for the triple negative breast cancer group will receive treatment in two phases. * The first phase will be Paclitaxel, carboplatin, and pembrolizumab over a 21 day cycle for 4 cycles. * The second phase will be doxorubicin, cyclophosphamide, and pembrolizumab over a 21 day cycle for 4 cycles. Participants who elect to take part in the optional observational studies will provide use of medical records for comparison of Duffy null and non-Duffy null populations. Participants who elect to take part in the optional short surveys will complete the short surveys. It is expected that about 90 people will take part in this research study, 60 in the treatment study, and 30 in the observational study. The Principal Investigator of this study and Dana-Farber Cancer Institute are the primary sponsors of this study.