Abstract
T-cell lymphoma involvement of the breast is rare and represents a diagnostic challenge. Here, we present a case of T-cell acute lymphoblastic leukemia (ALL) in a 20-year-old woman who presented in September 2023 with a history of bilateral breast enlargement associated with general weakness, weight loss, and a feeling of heat, which had lasted for about two months. She was examined clinically and found to have huge bilateral breast enlargement. A breast ultrasound (US) was performed and showed a diffuse abnormal heterogeneous parenchymal appearance of both breasts with multiple enlarged bilateral axillary lymph nodes. The patient was referred to the Military Cancer Center for breast core biopsy, which showed bilateral breast involvement by T-cell lymphoblastic lymphoma. Subsequently, bone marrow examination revealed T-cell ALL. The patient was started on the augmented Berlin-Frankfurt-Münster protocol, achieved complete remission, and maintained it for two years after diagnosis. ALL in the breast is rare but should be considered especially in young patients presenting with sudden breast masses.