INTRODUCTION
Cutaneous B-cell lymphomas (CBCLs) are indolent lymphomas presenting in the skin. Primary CBCL is classified according to the WHO/EORTC into three types1: primary cutaneous marginal zone lymphoma (PCMZL), primary cutaneous follicle center lymphoma (PCFCL), and primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT). While PCMZL and PCFCL are generally recognized as indolent diseases with 95% to 99% 5-year survival rate, PCDLBCL-LT has a more aggressive behavior with 5-year survival rates of 50%.2 The incidence of cutaneous T-cell lymphomas (CTCL), specifically of mycosis fungoides (MF), is increased significantly in African Americans (AAs) versus white individuals.3-6 AA patients with CTCL present with an earlier age of onset, and a higher stage at presentation.3 MF in AA patients is associated with disease progression and poorer survival.7-9Primary CBCL is much less common than MF.4 Unlike MF, its incidence in AA patients is significantly lower compared to white patients.3,4,10,11 Given its rarity, there is limited data on presentation and clinical behavior of CBCL in AAs.12 We attempted to characterize the disease presentation and course in this group.
METHODS
We retrospectively searched the tumor registry and pathology reports database for patients with CMZL/CFCL who were diagnosed and followed at our institution between 1997-2016. We defined CMZL/CFCL as skin lesions with histology either consistent with primary CBCL or secondary cutaneous presentation of systemic B-cell lymphoma. Our inclusion criteria were: (1) CMZL/CFCL histology confirmed by pathologists at MSKCC; (2) skin as initial site of involvement by the lymphoma; (3) staging imaging study [positron emission tomography (PET) scan and/or chest, abdomen, and pelvic computed tomography (CT) scan] completed within 12 months of diagnosis. This study was approved by the institutional review board of Memorial Sloan Kettering Cancer Center.Demographic and clinical data were collected from the medical records including age, sex, race and ethnicity, disease distribution, and clinical T classification (according to the ISCL/EORTC TNM staging system13) initial staging results and follow-up data. Race and ethnicity were reported by the patient or their representative upon admission/registration in accordance with the US Census Bureau’s race and ethnicity categories.All demographic and clinical parameters were compared using