Introduction/Background Primary Breast Lymphoma (PBL) Is A Rare Entity.Because Of Its Non Specific Presentation, It Had Diagnostic And Therapeutic challenges.

To describe the clinicopathological and therapeutic features of this uncommon malignancy.

Methodology We report two cases of PBL, treated at the radiation (RT) oncology department in Sousse, Tunisia in 2006 and 2023.

Results Case 1: A woman in her early 50s, presented with a 1 cm left breast nodule with an ipsilateral axillary adenopathy. Mammography showed a BI-RADS 5 lesion. Core needle biopsy confirmed a diffuse large B-cell lymphoma (DLBCL). LDH concentration was above normal and no other lesions were detected in the CT scan. With the diagnosis of Ann Arbor stage IIE PBL, she was treated according to the Non-Hodgkin Lymphoma (NHL) 2002 protocol, which consisted of ACVBP (doxorubicin,cyclophosphamide,vindesine,bleomycin,prednisone) chemotherapy (CT) followed by locoregional RT at a dose of 50 Gy in 25 fractions. After five years of follow-up,there was no relapse.

Case 2: A 35 year-old female complained of a palpable right breast mass.Mammography revealed a BI-RADS 5 lesion.The biopsy confirmed the diagnosis of DLBCL. LDH levels exceeds the normal ranges.The PET/CT scan, bone marrow biopsy and lumbar puncture (LP) returned normal results. The patient was diagnosed as being at stage Ie lymphoma with an international prognostic index (IPI) score of 1 and was treated according to the NHL 2013 protocol, including 8 cycles of R-CHOP therapy (rituximab,cyclophosphamide,doxorubicin,vincristine,prednisone) and 4 LP prophylaxis. A follow-up PET/CT scan showed a complete response. Currently, she in undergoing consolidative RT at a dose of 30 Gy in 15 fractions to her right breast.

Conclusion The management of PBL has not been standardised yet. Surgery is not recommended and was associated with poor survival.Combined CT and RT is the most consensual option with favorable results such as our patients. Further studies are needed to determine optimal treatment strategies.

Disclosures All authors declare that they have no conflicts of interest.