Radiological imaging and bone marrow biopsy in staging of cutaneous B‐cell lymphoma

Abstract

Primary cutaneous B-cell lymphoma (PCBCL) refers to Blymphocyte derived lymphoma that develops in the skin without any extracutaneous involvement at the time of diagnosis (Kempf et al, 2012). PCBCL constitutes approximately 25–30% of all primary cutaneous lymphoma cases with an incidence of approximately 3–3 5 cases per million personyears (Bradford et al, 2009; Kempf et al, 2012). Primary cutaneous large B-cell lymphoma, leg-type (PCLBCL; 4% of primary cutaneous lymphomas), primary cutaneous follicle centre lymphoma (PCFCL; 11%), and primary cutaneous marginal zone lymphoma (PCMZL; 7%) are the three major types of PCBCL, with PCMZL being included in the broad category of extranodal marginal zone lymphoma of mucosaassociated lymphoid tissue in the 2016 revised World Health Organization (WHO) classification of lymphomas (Willemze et al, 2005; Swerdlow et al, 2016). The 5-year overall survival for PCFCL and PCMZL is 95% or more while that of PCLBCL is about 50% (Willemze et al, 2005). Current guidelines recommend obtaining staging Positron emission tomography/computed tomography (PET/CT) scan and/or CT scan for all PCBCL, and bone marrow biopsy for at least PCLBCL-leg type variant (Kempf et al, 2012; National Comprehensive Cancer Network, 2017). However, evidence supporting these recommendations, especially radiological imaging, is lacking. We sought to address this gap by retrospectively collecting demographics, white blood cell (WBC) count at diagnosis, lactate dehydrogenase (LDH) at diagnosis, and results of staging CT-scan, PET/CT-scan, singlephoton emission computed tomography scan (SPECT-scan) and bone marrow biopsy (BMBx) on all patients seen at our institute between 2001 and 2017 who had presented with a skin lesion and had a biopsy diagnostic of B-cell lymphoma. Patients without any radiological imaging at diagnosis and those diagnosed with diffuse large B-cell lymphoma (DLBCL), marginal zone lymphoma (MZL) or follicular lymphoma (FL) prior to cutaneous manifestation were excluded. A total of 75 patients met our study criteria (95% Caucasian, 57% male). Cutaneous biopsies showed follicle centre histology (n = 18; 24%), marginal zone histology (n = 37; 49%), or large B-cell histology (n = 20; 27%). Staging CT-