A Novel del(20q) in Aggressive Nodal Marginal Zone Lymphoma

This is a case report of a previously undescribed 20q chromosomal deletion (del(20q)) in marginal zone lymphoma (MZL). A 54-year-old Caucasian male presented with an enlarging neck mass and multiple violaceous skin nodules over his chest. Biopsy of the neck mass and cervical lymph nodes revealed MZL. Cytogenetic evaluation of both lymph node and bone marrow tissue revealed del(20q). This was an unexpected finding, as del(20q) is associated with myelodysplastic syndromes and myeloproliferative neoplasms and rarely seen in diffuse large B-cell lymphoma, follicular lymphoma, and T-cell lymphoma, but has not previously been described in MZL. We describe the case presentation and histologic findings and discuss the significance of this novel finding. 1. Introduction 20q chromosomal deletion (del(20q)) is a well-described cytogenetic abnormality in myeloid neoplasms such as myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), and the myeloproliferative neoplasms (MPN) [1]. Del(20q) is rare in lymphomas, but has been detected in cases of diffuse large B-cell lymphoma, follicular lymphoma, and T-cell lymphoma [1]. A literature search and the National Cancer Institute’s Recurrent Chromosome Aberrations in Cancer Database failed to reveal any reported cases of del(20q) in marginal zone lymphoma (MZL) [2]. Here we present the first reported case of MZL with del(20q), detected by FISH in lymph node tissue and by karyotyping in involved bone marrow tissue. 2. Case Presentation The patient is a 54-year-old Caucasian man with a slowly enlarging neck mass, accompanied by multiple violaceous skin nodules over his chest and neck and B symptoms. Physical exam revealed an ？cm tender, erythematous right neck mass as well as multiple violaceous, mobile skin nodules on the neck and chest. Splenomegaly was not present. Also of note, the patient is hepatitis C virus positive, which is associated with MZL [3]. A CT of the neck revealed a large, poorly defined right neck mass measuring up to 9？cm as well as many enlarged cervical lymph nodes. An open biopsy was performed and a right posterior cervical lymph node and tissue from the deep neck mass were sent for histologic evaluation. Microscopic examination showed almost complete effacement of the node (Figure 1(A)). Follicles were replaced by atypical monocytoid cells (Figures 1(B) and 1(C)), which stained positive for PAX-5, CD19, and CD20, but were negative for CD5 and cyclin D1. The effaced area had a MIB-1 labeling index of 10%. BCL-6 and CD23 were diffusely positive in remnant germinal centers which were replaced by