Study of the P16 Gene as a Predictor of Myelosuppression in Breast Cancer Patients

Inclusion Criteria: * ≥ 18 years of age; * Histologically confirmed Stage I-IV breast cancer; * ECOG Performance Status 0-3; * Scheduled to start a new course of chemotherapy in the neo-adjuvant, adjuvant or metastatic setting for newly diagnosed or recurrent disease; * Growth factors, e.g., filgrastim, pegfilgrastim, are allowed, but their dose and duration will be tracked. * Absolute Lymphocyte Count (ALC) \> 500 cells/μL as determined by routine CBC with differential; * Signed, IRB approved written informed consent. Exclusion Criteria: * Presence of acute, active infection; * History of clonal bone marrow disorder (i.e., myelodysplastic or myeloproliferative disorder, acute or chronic leukemia); * Other co-morbid illness which would impair ability to participate in the study; * Concurrent experimental therapy (Note: concurrent biologic therapy IS permitted, provided it is not experimental). * Prior or current receipt of histone deacetylase (HDAC) inhibitors