Abstract
Anaplastic lymphoma kinase (ALK)-positive diffuse large B-cell lymphoma (ALK+ DLBCL) is characterized by the presence of immunoblastic or plasmablastic cells with a strong ALK protein expression that is frequently associated with t(2;17)(p23;q23). The present study reports a case of ALK+ DLBCL in a 26-year-old male with a duodenal mass. Histologically, the neoplastic cells demonstrated prominent plasmablastic differentiation with abundant amphophilic cytoplasma and central nucleoli. Paraffin immunohistochemistry revealed: an exclusively cytoplasmic granular expression of ALK; CD138, immunoglobulin A (IgA) and CD79α positivity; and focal expression of multiple myeloma oncogene 1 (Mum-1), CD30 and epithelial membrane antigen (EMA). However, the immunohistochemical staining was negative for CD3, CD38 and CD20. Fluorescence in situ hybridization (FISH) analysis using an ALK break-apart probe revealed the presence of ALK gene rearrangements in the patient. To the best of our knowledge, the current case represents the first example of primary extranodal ALK+ DLBCL presenting as a duodenal mass.
Highlights
Anaplastic lymphoma kinase (ALK)‐positive diffuse large B‐cell lymphoma (ALK+ DLBCL) is a rare novel subtype of DLBCL that was recognized as a separate entity in the 2008 World Health Organization (WHO) classification of lymphoid neoplasms [1]
An ALK gene rearrangement was not detected in ALK+ DLBCL and the full‐length ALK protein was considered to be the pathogenesis of the lymphoma [2]
The analyses were conducted with a large panel of monoclonal antibodies, including antibodies against CD20, CD79α, CD3 (BD Biosciences, Heidelberg, Germany), CD138, CD38, CD56, epithelial membrane antigen (EMA), AE1/AE3, CD30, multiple myeloma oncogene 1 (Mum‐1), CD10, B-cell lymphoma 6 (Bcl‐6; BD Biosciences), immunoglobulin A (IgA; DAKO, Glostrup, Denmark) and Ki67 (ZSGB-BIO), following antigen retrieval
Summary
In 2003, Gascoyne et al [4] and De Paepe et al [5] described six and three cases, respectively, of ALK+ DLBCL. They were characterized by t(2;17)(p23;q23), which results in the fusion of the ALK gene at chromosome band 2p23 and the clathrin gene (CLTC) at 17q2. Subsequent studies revealed chromosome translocation at t(2;5)(p23;q35), which was frequently associated with ALCL, and a cryptic insertion of the ALK gene into chromosome 4 at band 4q22‐24 fusion in certain cases of ALK+ DLBCL [6,7,8].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
