Adolescent Adult Aged Aged, 80 and over Antineoplastic Agents--therapeutic use Breast Neoplasms--diagnosis Chemotherapy, Adjuvant Cohort Studies Female Health Status Disparities Healthcare Disparities--statistics & numerical data Humans Mastectomy Middle Aged North Carolina--epidemiology Outcome and Process Assessment, Health Care Prognosis Registries Retrospective Studies Survival Analysis Time Factors Young Adult