Primary breast diffuse large B-cell lymphoma: a population-based study from 1975 to 2014.

Area of Science:

• Oncology
• Hematology
• Epidemiology

Background:

• Primary breast diffuse large B-cell lymphoma (DLBCL) is a rare non-Hodgkin's lymphoma with limited epidemiological data.
• Understanding incidence trends, prognostic factors, and treatment outcomes is crucial for this distinct patient population.

Purpose of the Study:

• To determine incidence trends, prognostic factors, and survival rates of primary breast DLBCL in the US.
• To evaluate the role of surgery and compare outcomes with nodal DLBCL.
• To analyze the impact of diagnostic era and treatment advancements on breast DLBCL survival.

Main Methods:

• Population-based study utilizing Surveillance, Epidemiology, and End Results (SEER) cancer registries (1973-2014).
• Inclusion of 1021 patients diagnosed with primary breast DLBCL.
• Multivariate analysis to identify independent predictors of overall survival (OS) and disease-specific survival (DSS).

Main Results:

• Incidence of both breast and nodal DLBCL increased over time.
• Breast DLBCL patients were older, predominantly female, diagnosed at earlier stages, and had lower prevalence in white and black races compared to nodal DLBCL.
• Older age (≥70) and advanced stage predicted worse OS, while younger age (<70), early stage, and post-2000 diagnosis predicted better DSS. Surgery offered survival benefit only in specific diagnostic periods (2001-2010), with decreasing utilization over time. Breast DLBCL generally had better outcomes than nodal DLBCL.

Conclusions:

• Primary breast DLBCL incidence is increasing, with significant survival improvements observed over four decades.
• The introduction of rituximab appears to positively impact breast DLBCL outcomes.
• Further research is necessary to refine understanding and optimize treatment strategies for breast DLBCL.