Supplementary Material for: Primary diffuse large B cell lymphoma (DLBCL) of the breast with MYC and BCL2 rearrangements with terminal deoxynucleotidyl transferase (tdt) expression

Primary breast lymphoma represents only 1% of Non-Hodgkin lymphomas. The most common histology is diffuse large B cell lymphoma. When dual translocations of MYC and BCL2 or BCL6 occurs, it is referred to as "High grade B-cell lymphoma with rearrangements of MYC and BCL2 and/or BCL6" according to the 4th edition of the WHO classification of hematolymphoid tumors.This is a case of 54 years old woman presenting with a rapidly growing painless mass. Ultrasound-guided core biopsy of the breast mass showed infiltrate of medium -sized neoplastic lymphocytes which stained as CD79a-positive B-cells co-expressing CD10, BCL2, tdt, and MYC. Ki-67 is positive in 80%. There was Rearrangement of Myc and Bcl2 at FISH. PET scan was negative elsewhere. She was treated with 6 cycles of R-hyperCVAD/MA (R= rituximab, c= cyclophosphamide, v= vincristine, A=cytarabine, D= dexamethasone, M= Methotrexate) and intrathecal chemotherapy (IT CT). Restaging PET show resolution of all avid uptake. We did a review of literature showing the importance of giving an intensive chemotherapy regimen, high dose Methotrexate and cytarabine and IT CT for central nervous system (CNS) prophylaxis. Primary DLBCL of the breast with rearrangement of Myc and bcl2 is an aggressive disease that need to be treated with an intensive CT and CNS prohylaxis. Stem cell transplant (SCT) could be given after first remission.