Prevalence and clinical implications of bone marrow involvement in pediatric anaplastic large cell lymphoma

Leukemia. 2005 Sep;19(9):1643-7. doi: 10.1038/sj.leu.2403888.


Anaplastic large cell lymphoma (ALCL) harbors the reciprocal chromosomal translocation t(2;5)(p23;q35) in approximately 80% of the cases. The genes involved are nucleophosmin (NPM) and anaplastic lymphoma kinase (ALK) and the resulting chimeric NPM-ALK protein is thought to play a key role in the pathogenesis of t(2;5) positive ALCL. Few data on bone marrow (BM) involvement in ALCL have been published and they mostly rely on morphological examination of BM smears. We studied 52 ALCL for NPM-ALK expression by RT-PCR: 47/52 biopsies were positive. In 41 of the 47 cases we obtained the BM at diagnosis and investigated the prevalence of minimal BM infiltration by RT-PCR and real-time PCR. Minimal disseminated disease was positive in 25/41 patients (61%), of whom six had morphologically infiltrated BM. Survival analysis demonstrated a 5-year progression-free survival of 41 +/- 11% for patients with molecularly positive BM vs 100% for patients with negative BM (P = 0.001). These results suggest that minimal BM involvement at diagnosis is a common event in pediatric ALCL and that minimal BM disease monitoring could identify patients at risk of relapse.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Bone Marrow / metabolism*
  • Bone Marrow / pathology
  • Child
  • Child, Preschool
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Infant
  • Lymphoma, Large B-Cell, Diffuse / diagnosis*
  • Lymphoma, Large B-Cell, Diffuse / genetics*
  • Lymphoma, Large B-Cell, Diffuse / metabolism
  • Male
  • Neoplasm, Residual
  • Nuclear Proteins / genetics
  • Nucleophosmin
  • Prospective Studies
  • Protein-Tyrosine Kinases / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Survival Analysis


  • NPM1 protein, human
  • Nuclear Proteins
  • Nucleophosmin
  • p80(NPM-ALK) protein
  • Protein-Tyrosine Kinases