Primary non-Hodgkin’s lymphoma of the breast: First report of the multicentre retrospective study of the International Extranodal Lymphoma Study Group (IELSG-15)

Abstract

6575 Background: Primary breast lymphoma is a rare poorly-defined condition. This large multi-centre retrospective review investigates its prognosis and patterns of relapse. Methods: Patients presenting with histologically-proven primary non-Hodgkin’s lymphoma of one or both breasts between 1980 and 2003 are included. Data was obtained retrospectively from patient medical records. Central histology review was undertaken where possible. Survival curves were estimated using the Kaplan-Meier method, and prognostic factors analysed by univariate and multivariate analysis. The major study endpoints were progression-free and overall survival. Results: A total of 276 eligible patients were identified. Of these, 202 patients had diffuse large B-cell histology, and form the basis of this analysis. Sixty-seven percent of patients had Stage IE disease, 28% were stage IIE, and 5% were stage IVE(bilateral). B-symptoms were present in 4%. International Prognostic Index (IPI) was 0,1,2 and 3 in 27,37,15 and 3%, respectively. Eighty percent of patients received chemotherapy, 64% radiotherapy, and 50% both, with 87% of patients achieving a complete response at the end of planned first-line therapy. Thirty-seven percent of patients subsequently progressed in one or more sites. The crude rates for recurrence in breast, loco-regional nodes, and central nervous system (CNS) were 15%, 6%, and 5%. Only one breast relapse occurred in an irradiated breast. The median progression-free survival was 5.9 years (95% CI: 3.7, 8.0), with a median follow-up duration of 5.5 years. Median overall survival was 8.4 years (95% CI: 6.5, 10.9). The only statistically significant prognostic factor on multifactor analysis was IPI. Conclusions: The outcome for patients presenting with primary diffuse large B-cell non-Hodgkin’s lymphoma of the breast was significantly worse than that anticipated for Stage I and II nodal lymphomas treated during a similar period. The data suggests that future prospective studies should investigate intensification of treatment, and that the addition of specific prophylactic therapy targeted at the major sites of recurrence may improve prognosis. No significant financial relationships to disclose.