[Primary lymphoma of breast: a clinicopathologic, immunophenotypic and prognostic study of 21 cases].

Objective To investigate the clinicopathologic and immunophenotypic features of primary breast lymphoma (PBL) and to discuss the diagnosis pof the tumor. Methods Twenty-one cases of PBL with follow up data were clinically reviewed. The histologic diagnosis of the tumor was based on the Pupdated WHO Classification of tumors of hematopoietic and lymphoid tissues (2008 ). Immunohistochemistry was performed by SP method and antibodies uselected were as follows; CD20, CD3e, CD10, Bcl-6, MUM-1, CD5, Bcl-2, CD23, CD10, cyclin Dl, CD43 and Ki67. Results (1) All 21 patients were female wand the median age of patients was 48 years. The right and the left breasts were involved in 11 (52.4% ) and 10 patients (47. 6% ), respectively. According to Ann Carbor staging system, 20 cases were stage Ⅰ -Ⅱ (95. 2% ) , and the remaining case was stage Ⅳ (4. 8% ). For the international prognostic index (IPI) , 19 cases mwere score 0- 1, and 2 cases were score 2-3. For ECOG score, 19 cases were 0, and the remaining 2 cases were 1. (2) Histologically, all 21 cases (100%) were pDLBCL Immunohistochemically, the frequency of antigen expression was as follows: CD20 (100% ) , MUM-1 (14/21,66. 7% ), bcl-6 (5/21, 23.8%), CD10 (0), (bcl-2 (13/21,61.9%), CD5 (1/21,4.8%); Ki-67 index; 10 cases (47.6%) were less than 59% , with the expression of seven cases (33. 3% ) being 60% - 89% , and cmore than 90% in the remaining four cases (19. 1% ). The median Ki-67 index was 60%. All the cases were considered non germinal center B-cell-like type of 2DLBCL. (3) Follow-up data was available in 64% of the cases.f2 One, two and five-year survival rates were 11 cases, 7 cases and 3 cases, respectively. Conclusion All the cases of PBL in the current study were DLBCL, non germinal center B-cell-like type, and a diagnosis of PBL can only be established after excluding breast involvement in systemic lymphoma. Key words: Breast neoplasms;  Lymphoma;  Immunophenotyping;  Diagnosis;  Prognosis