When Bilateral Mastitis is not Mastitis: Primary Breast Burkitt Lymphoma in Pregnancy - A Case Report and Literature Review

Background Primary breast Burkitt lymphoma (PB-BL) is a rare, aggressive, malignant tumor of the breast that affects women of reproductive age during pregnancy or lactation. It can mimic benign and inflammatory conditions, leading to delayed diagnosis that inversely affects the prognosis. Here, we present a case of lactating women with no identifiable risk factors who were misdiagnosed as inflammatory mastitis, delaying the diagnosis to the postpartum period. Case Presentation A 32-year-old female in her third trimester of pregnancy presented with progressive bilateral breast enlargement and was initially mismanaged as inflammatory mastitis that failed to respond to multiple courses of antibiotic therapy. Following the delivery, as the woman continued to suffer with no improvement, the imaging study and mammography showed multiple matted heterogeneous, hypoechoic masses with increased vascularity and bilateral massive breast-positive axillary lymph nodes consistent with BIRAD-4c, suggesting malignancy. Multiple breast biopsies were taken with fine needle aspiration of the lymph nodes. Histopathology and immunohistochemistry revealed a starry sky morphology with Ki-67 proliferation, c-MYC overexpression, and CD10 positivity, confirming the diagnosis of primary breast B-cell lymphoma of the non-Hodgkin type. Intensive chemotherapy was started with follow-up. Conclusion The physician should practice a high index of suspicion when a breast condition presents with an aggressive course or when it fails to respond to medical therapy, even in the absence of risk factors. Imaging can help exclude potential diagnoses, but the gold standard remains histopathology and immunohistochemistry. The current case emphasizes the importance of early diagnosis and timely intervention, which are positively associated with improved patient survival.