ALK activation by the CLTC-ALK fusion is a recurrent event in large B-cell lymphoma

Blood. 2003 Oct 1;102(7):2638-41. doi: 10.1182/blood-2003-04-1050. Epub 2003 May 15.


We present 3 cases of large B-cell lymphoma (LBCL) with a granular cytoplasmic staining for anaplastic lymphoma kinase (ALK). All of the cases showed striking similarities in morphology and immunohistochemical profile characterized by a massive monomorphic proliferation of CD20-/CD138+ plasmablast-like cells. In one of the cases, initially diagnosed as a null-type anaplastic large cell lymphoma (ALCL), the B-cell phenotype became evident only at recurrence. Fluorescent in situ hybridization (FISH) and molecular studies led to the detection of a CLTC-ALK rearrangement in all 3 cases, without any evidence of full-length ALK receptor expression. The associated t(2;17)(p23;q23) was demonstrated in the karyotype of 2 cases. Although a similar CLTC-ALK aberration was previously identified in ALK-positive T-/null cell ALCL and inflammatory myofibroblastic tumor, its association with ALK-positive LBCL seems to be specific and intriguing.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Adult
  • Amino Acid Sequence
  • Anaplastic Lymphoma Kinase
  • Base Sequence
  • Child
  • Chromosomes, Human, Pair 17
  • Chromosomes, Human, Pair 2
  • Clathrin / genetics*
  • Female
  • Genotype
  • Humans
  • Lymphoma, B-Cell / genetics*
  • Lymphoma, B-Cell / metabolism*
  • Male
  • Molecular Sequence Data
  • Oncogene Proteins, Fusion / genetics
  • Oncogene Proteins, Fusion / metabolism*
  • Phenotype
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • Receptor Protein-Tyrosine Kinases


  • Clathrin
  • Oncogene Proteins, Fusion
  • oncoprotein CLTCL-ALK
  • ALK protein, human
  • Anaplastic Lymphoma Kinase
  • Protein-Tyrosine Kinases
  • Receptor Protein-Tyrosine Kinases