title: ALK-positive anaplastic large-cell lymphoma: strong T and B anti-tumour responses may cause hypocellular aspects of lymph nodes mimicking inflammatory lesions.
abstract: The anaplastic large cell lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) is a rare type of non-Hodgkin lymphoma which occurs in children mostly. The ALK protein is highly immunogenic and elicits both humoral and cellular immune responses. A 15-yr-old child presented with fever and adenopathy and did not respond to antibiotics. Biopsy of the enlarged lymph node contained almost no lymphoid element except for a few CD8-positive T cells, plasma cells and isolated CD30-positive blasts. The patient's condition improved following lymphadenectomy but relapse occurred 3 months later with multiple nodes, high fever and an abdominal mass. This time an ALK-positive ALCL was diagnosed and the retrospective analysis of the initial biopsy revealed rare, isolated ALK+ cells. Molecular analysis showed T-cell clones and oligoclonal B cells in both biopsies and peripheral blood of the patient. The tumour cells harbour a t(2;5) translocation, revealing a null phenotype by immunohistochemistry and no evidence for T-cell clonality by Southern blotting. The patient's serum contained anti-ALK antibodies. Our findings suggest that the T-cell clones and anti-ALK antibodies in this patient constitute an anti-tumour response that caused the hypocellularity of the initial lymph node. Hypocellular and oedematous lymph nodes occurring in a child with evocative symptoms should be tested for the presence of ALK.
authors.affiliation: Department of Pathology, University Hospital of Geneva, Geneva, Switzerland. bettina@borisch.ch
authors.forename: B
authors.initials: B
authors.lastname: Borisch
authors.forename: S
authors.initials: S
authors.lastname: Yerly
authors.forename: Ch
authors.initials: Ch
authors.lastname: Cerato
authors.forename: J
authors.initials: J
authors.lastname: Schwaller
authors.forename: P
authors.initials: P
authors.lastname: Wacker
authors.forename: A H
authors.initials: AH
authors.lastname: Ozsahin
authors.forename: N
authors.initials: N
authors.lastname: Brousse
authors.forename: D C
authors.initials: DC
authors.lastname: Hoessli
mesh_terms: D000293:Adolescent; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D015139:Blotting, Southern; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D007249:Inflammation; D017730:Ki-1 Antigen / Q000096:biosynthesis; D008198:Lymph Nodes / Q000166:cytology / Q000473:pathology; D008207:Lymphatic Metastasis; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics* / Q000473:pathology*; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics; D008957:Models, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*; D013997:Time Factors; D014178:Translocation, Genetic
chemical_list: D017730:Ki-1 Antigen; D012333:RNA, Messenger