Hematolymphoid neoplasms involving the breast: A single institution clinicopathologic study of 59 patients

Breast hematopoietic neoplasms (BHN) are rare and may either primarily (PBHN) or secondarily (SBHN) involve breast tissue. The widespread use of needle biopsy for diagnosis of breast lesions necessitates knowledge of their presentation, radiologic aspects, histomorphology, and outcomes for seeking appropriate hematopathology consultation. Herein, we present our clinical experience as an academic institution and referral center of BHN in the past 20 years. We identified 59 patients diagnosed at the University of Chicago Medical Center between 2002-2021. Demographic, pathologic, radiologic, therapy, relapse data, and vital status were abstracted. Data were examined using univariable statistics with event-free and overall survival (EFS, OS) as primary outcomes examined with the lymphoma subgroup using Cox PH regression adjusted for age. The cases included 27 (46%) PBHN and 32 (54%) SBHN in a cohort comprising 93% females, mostly white (56%). The mean age at diagnosis was 58.8 years. Lymphomas were the most frequent BHN (86.4% of all cases). Patients with primary breast lymphomas (PBL) were significantly older than those with secondary breast lymphomas (SBL) (61.2 vs. 49.8 yrs, p