Work

Transformation of marginal zone lymphoma to Hodgkin lymphoma

Year: 2024

Type: article

Abstract: Marginal zone lymphomas (MZLs) make up 5% to 10% of non-Hodgkin lymphomas.1,2 In the United States, extranodal MZL (EMZL) is the most common subtype (61%), followed by nodal MZL (NMZL; 30%) and splenic MZL (SMZL; 9%), with an increased incidence across all subtypes with age.2,3 MZL is characterized by an indolent course with a characteristic clinical presentation by subtype.EMZL frequently presents with localized mucosa involvement at diagnosis.SMZL commonly involves the spleen, bone marrow, and peripheral blood and less frequently the lymph nodes.4 NMZL typically presents with lymphadenopathy, occasionally involving the bone marrow or peripheral blood, and without splenic or extranodal involvement.5 The overall survival (OS) of patients with MZL is favorable with a 5-year relative survival rate of 90%. 2 In a subset of patients, MZL transforms to more aggressive lymphomas, most commonly to diffuse large B-cell lymphoma (DLBCL).Transformation has been shown to be an independent risk factor for a shortened OS. 6 Failure to achieve complete response (CR) after initial treatment, elevated lactate dehydrogenase, and >4 nodal sites at the time of MZL diagnosis have been associated with histologic transformation to DLBCL.[6][7][8][9] Rarely, MZL can also transform to Hodgkin lymphoma (HL).10,11 This event is poorly understood with fewer than 10 cases reported in the literature.[11][12][13][14][15] Furthermore, whether this represents transformation of MZL or co-occurrence is unknown.In this study, we report, to our knowledge, 1 of the largest cohorts of MZL transformation to HL and elucidate the clinical characteristics of this rare event.A total of 10 patients with transformation from MZL to HL were identified at the University of Miami (5 patients), the University of Iowa (1 patient), and the Mayo Clinic (4 patients).At the University of Miami, the cases were identified by search of an MZL database containing 757 cases of MZL diagnosed from June 1996 to July 2023.Of the 757 patients, 5 had biopsy-proven transformation to HL (0.66%).At the University of Iowa and the Mayo Clinic, data were collected from 2 sources, namely the Molecular Epidemiology Resource and the Mayo Lymphoma Database.16 The Molecular Epidemiology Resource prospectively enrolled and followed 529 cases of MZL diagnosed from 2002 to 2015, and 3 of those cases subsequently transformed to HL (0.56%).The Mayo Lymphoma Database contained 347 cases of MZL diagnosed between 1995 and 2002, and 2 of those cases transformed to HL (0.57%).The clinical characteristics were collected from electronic medical records.Staging was based on imaging, which included computed tomography scans, positron-emission tomography, and bone marrow biopsy as per the discretion of the treating physicians.The study was approved by the institutional review boards.All the biopsies were reviewed at the time of diagnosis by expert hematopathologists at each institution.Ten patients with MZL who transformed to HL were identified, including 6 patients initially diagnosed with SMZL, 3 with EMZL, and 1 with NMZL.The clinical characteristics of the patients are summarized in Table 1.The median age at MZL diagnosis was 65 years (range, 25-75) with a male to female ratio of

Source: Blood Advances

DOI: 10.1182/bloodadvances.2024013434