MYC cytogenetic status correlates with expression and has prognostic significance in patients with MYC/BCL2 protein double-positive diffuse large B-cell lymphoma

Am J Surg Pathol. 2015 Sep;39(9):1250-8. doi: 10.1097/PAS.0000000000000433.

Abstract

MYC/BCL2 double-hit lymphoma (DHL), defined by conventional cytogenetic or fluorescence in situ hybridization (FISH) analysis, and MYC/BCL2 double-positive lymphoma (DPL), defined by immunohistochemistry, are associated with a poor prognosis. However, DHL and DPL are not concordant, and it is unclear whether MYC and BCL2 aberrations have prognostic impact in DPL patients. In a cohort of 135 patients diagnosed with large B-cell lymphoma between 2010 and 2014 in whom MYC/8q24 and BCL2/t(14;18)(q32;q21) statuses were assessed by FISH at diagnosis, we evaluated MYC and BCL2 expression by immunohistochemistry. A total of 54 (40%) cases were positive for MYC and BCL2 supporting DPL. Among them, 19 (35%) had MYC rearrangement including 11 DHLs, 12 (22%) had multiple copies of MYC, 19 had no MYC abnormalities, and in 4 cases FISH analysis failed. BCL2 abnormalities were present in 28/54 (52%) cases (20 rearranged and 8 multiple copies). MYC rearrangement correlated with a significantly worse overall survival in DPL (P<0.05), whereas BCL2 genetic status did not correlate with survival (P>0.05). MYC and BCL2 expression by immunohistochemistry correlates with gene status by FISH; however, immunohistochemistry is neither specific nor adequately sensitive to be used as a surrogate for MYC and BCL2 gene status using any cutoff level. In conclusion, MYC rearrangement identifies a subset of patients with DPL who have a significantly worse prognosis. Although immunohistochemical assessment for MYC and BCL2 may be a helpful initial screen to identify higher-risk patients, FISH analysis for MYC remains important for further risk stratification in patients with DPL.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / analysis
  • Biomarkers, Tumor / genetics*
  • Female
  • Gene Amplification
  • Gene Rearrangement
  • Genetic Predisposition to Disease
  • Humans
  • Immunohistochemistry*
  • In Situ Hybridization, Fluorescence*
  • Kaplan-Meier Estimate
  • Lymphoma, Large B-Cell, Diffuse / chemistry
  • Lymphoma, Large B-Cell, Diffuse / genetics*
  • Lymphoma, Large B-Cell, Diffuse / mortality
  • Lymphoma, Large B-Cell, Diffuse / pathology
  • Male
  • Middle Aged
  • Phenotype
  • Predictive Value of Tests
  • Prognosis
  • Proto-Oncogene Proteins c-bcl-2 / analysis
  • Proto-Oncogene Proteins c-bcl-2 / genetics*
  • Proto-Oncogene Proteins c-myc / analysis
  • Proto-Oncogene Proteins c-myc / genetics*
  • Reproducibility of Results
  • Time Factors
  • Young Adult

Substances

  • BCL2 protein, human
  • Biomarkers, Tumor
  • MYC protein, human
  • Proto-Oncogene Proteins c-bcl-2
  • Proto-Oncogene Proteins c-myc