title: Alternate clonal dominance in richter transformation presenting as extranodal diffuse large B-cell lymphoma and synchronous classic Hodgkin lymphoma.
abstract: OBJECTIVE
  Richter transformation (RT) represents the rare occurrence of a secondary aggressive lymphoma in the setting of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL).
  
  
  METHODS
  Here we describe the peculiar case of a patient with trisomy 12+ and atypical (CD5+, CD23-) CLL/SLL who developed a two-step RT with complex morphologic and molecular features.
  
  
  RESULTS
  Molecular analysis of a CLL/SLL population detected two different immunoglobulin rearrangement patterns corresponding to a main peak and a minor peak. Transformation took place both as gastric diffuse large B-cell lymphoma and as a synchronous bone marrow classic Hodgkin lymphoma with the same immunoglobulin rearrangement pattern corresponding to the minor peak detected in CLL/SLL at diagnosis. During chemotherapy, progression occurred as axillary nodal involvement by a CD5+ high-grade lymphoma with an immunoglobulin rearrangement pattern corresponding to the main CLL peak.
  
  
  CONCLUSIONS
  In this case, the elaborate clinical and molecular picture may be correlated to an alternate dominance of two distinct clonal populations probably influenced by therapeutic and environmental factors.
authors.affiliation: From the Department of Anatomic Pathology, Orthopaedic Institute G. Pini, Milan, Italy; Andrea.DiBernardo@gpini.it.
authors.forename: Andrea
authors.initials: A
authors.lastname: Di Bernardo
authors.affiliation: Department of Hematology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy; Università degli Studi di Milano, Milan, Italy; and.
authors.forename: Alberto
authors.initials: A
authors.lastname: Mussetti
authors.affiliation: Department of Pathology and Laboratory Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Aiello
authors.affiliation: Department of Pathology and Laboratory Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: De Paoli
authors.affiliation: Department of Pathology and Laboratory Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
authors.forename: Antonello Domenico
authors.initials: AD
authors.lastname: Cabras
mesh_terms: D000368:Aged; D001853:Bone Marrow / Q000276:immunology / Q000473:pathology*; D002471:Cell Transformation, Neoplastic / Q000276:immunology / Q000473:pathology*; D006689:Hodgkin Disease / Q000175:diagnosis / Q000473:pathology* / Q000628:therapy; D006801:Humans; D007136:Immunoglobulins / Q000276:immunology / Q000378:metabolism; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis / Q000473:pathology* / Q000628:therapy; D008297:Male; D009378:Neoplasms, Multiple Primary / Q000473:pathology* / Q000628:therapy; D016896:Treatment Outcome
chemical_list: D007136:Immunoglobulins
keywords: Clonal dominance; Diffuse large B-cell lymphoma; Hodgkin lymphoma; Richter syndrome