TWO BREASTS, TWO ENTITIES: SYNCHRONOUS CARCINOMA AND MALT LYMPHOMA maria.gualter@hotmail.com

PW04-18

TWO BREASTS, TWO ENTITIES: SYNCHRONOUS CARCINOMA AND MALT LYMPHOMA

5

Portugal

Poster Exhibition only

Primary breast lymphoma is rare, representing less than 1% of all breast malignancies, with MALT lymphoma being an exceptional entity. Its clinical and radiological features often mimic breast carcinoma, making diagnosis challenging.

We present the case of a 68-year-old woman with a strong family history of hematological disease and breast cancer, referred after abnormal findings on screening mammography. Bilateral breast lesions were identified: a suspicious density in the right breast and a nodular lesion in the left breast. Core biopsies were performed.

Histology of the right breast lesion revealed invasive carcinoma, ER/PR positive and HER2 amplified. The left breast lesion demonstrated a dense lymphoid infiltrate with lymphoepithelial lesions, immunophenotype CD20+, CD79a+, BCL2+, and low Ki-67, consistent with MALT lymphoma. The patient underwent right breast lumpectomy with sentinel node biopsy, confirming localized disease. The left breast MALT lymphoma was treated after with combined chemotherapy and radiotherapy.

This case illustrates the diagnostic challenge of synchronous breast carcinoma and MALT lymphoma, a rare association requiring multidisciplinary management. Awareness of this entity is crucial to avoid misdiagnosis and to tailor therapy according to the distinct biological behaviors of these tumors.