High expression of the very late antigen-4 integrin independently predicts reduced risk of relapse and improved outcome in pediatric acute myeloid leukemia: a report from the children's oncology group.

Abstract

PURPOSE:

To evaluate the prognostic significance of the integrin cell adhesion molecule very late antigen-4 (VLA-4) in acute myeloid leukemia (AML).

PATIENTS AND METHODS:

We prospectively quantified VLA-4 expression in 216 patients enrolled onto COG-AAML03P1 by flow cytometry and correlated expression levels with disease characteristics and clinical outcome.

RESULTS:

VLA-4 mean fluorescence intensity (MFI) varied 35-fold (range, 30 to 1,110; median, 219.5). High VLA-4 expression (> median MFI), compared with low expression, was associated with younger age (7.1 v 12.1 years, respectively; P < .001), lower FLT3 internal tandem duplication prevalence (4% v 21%, respectively; P < .001), and higher likelihood of extramedullary disease (16% v 5%, respectively; P = .013). In low- and high-expression groups, rates of remission (89% v 80%, respectively; P = .137) and minimal residual disease (29% v 25%, respectively; P = .700) were similar. Patients with low VLA-4 expression, compared with high expression, had a higher relapse rate (RR; 44% +/- 10% v 24% +/- 9%, respectively; P = .011) and lower disease-free survival (DFS; 48% +/- 11% v 67% +/- 10%, respectively; P = .023) after 3 years. Multivariate analyses showed that low VLA-4 expression was an independent adverse prognostic factor for DFS (hazard ratio [HR] = 1.98; P = .038) and RR (HR = 2.77; P = .009). Subgroup analyses indicated that the prognostic role of VLA-4 expression was most prominent in patients with standard-risk AML, in whom low VLA-4 expression was associated with inferior DFS (34% +/- 16% v 69% +/- 14% for high expression; P = .011) and higher RR (61% +/- 16% v 26% +/- 14% for high expression; P = .009). A similar trend was seen in low-risk but not high-risk patients.

CONCLUSION:

High VLA-4 expression is associated with better clinical outcome in pediatric AML and is an independent predictor of relapse that may refine our abilities to stratify patients without identifiable cytogenetic or molecular risk factors.

• Authors: Roland B Walter, Todd A Alonzo, Robert B Gerbing, Phoenix A Ho, Franklin O Smith, Susana C Raimondi, Betsy A Hirsch, Alan S Gamis, Janet L Franklin, Craig A Hurwitz, Michael R Loken, Soheil Meshinchi
• Journal: Journal of clinical oncology : official journal of the American Society of Clinical Oncology (J Clin Oncol) Vol. 28 Issue 17 Pg. 2831-8 (Jun 10 2010) ISSN: 1527-7755 [Electronic] United States
• PMID: 20421533 (Publication Type: Journal Article)

Chemical References

• Integrin alpha4beta1

Topics

• Adolescent
• Adult
• Age Factors
• Child
• Child, Preschool
• Clinical Trials, Phase III as Topic
• Cohort Studies
• Flow Cytometry
• Humans
• Infant
• Integrin alpha4beta1 (biosynthesis)
• Leukemia, Myeloid, Acute (immunology, pathology, therapy)
• Male
• Prognosis
• Prospective Studies
• Treatment Outcome
• Young Adult