According to an article recently published in the Journal of the National Cancer Institute, gene expression profiling may help predict the risk of cancer progression among patients with neuroblastom who lack MYCN gene amplification.
Neuroblastoma is a disease in which cancerous cells form in the nerve tissues of the adrenal gland, neck, chest, or spinal cord. Although neuroblastoma is rare (it affects roughly 650 children and adolescents in the U.S. each year), it is the most common malignancy diagnosed in infants.
The severity of neuroblastoma is classified as “high”, “intermediate”, or “low”; classifications refer to the risk of a cancer recurrence or cancer progression following standard therapies. Patients classified as “low” have a significantly improved outcome compared to those classified as “high”.
Although some markers have already been established that help classify patients with neuroblastoma, researchers continue to define other variables that may be linked with certain outcomes; this research is part of an effort to individualize therapeutic approaches for patients with this disease. MYCN gene amplification is one known variable that is associated with a more aggressive course of neuroblastoma.
Gene expression profiling measures the expression of specific cancer genes. Gene expression profiling is becoming widely evaluated in clinical trials for various types of cancers because it has demonstrated the ability to identify subgroups of patients with the same disease who have different outcomes with standard therapies. By identifying these subgroups of patients, treatment may ultimately become individualized.
Researchers from Ohio and North Carolina recently conducted a clinical trial to evaluate the accuracy of gene expression profiling in patients with neuroblastoma who did not have MYCN gene amplification. This trial included 102 patients with newly diagnosed neuroblastomas who were between the ages of 0.1 months to 151 months.
- A gene signature including 55 genes could distinguish two separate groups of patients who were diagnosed over the age of 12 months.
- Among those diagnosed over the age of 12 months, the gene signature identified one group with a progression-free survival rate of 16% and the other group with a progression-free survival rate of 79%.
- The gene signature also identified two groups of patients from those who were diagnosed over the age of 18 months; one group had a progression-free survival rate of 15% and the other group had a progression-free survival rate of 69%.
The researchers concluded that gene expression profiling can help identify subgroups of patients with significantly varying outcomes following standard therapy. Those identified through gene expression profiling as having more aggressive disease may wish to undergo more aggressive therapies or enroll in a clinical trial, while those identified as having less aggressive disease may be spared from unnecessary side effects of aggressive therapies.
Parents with children who have neuroblastoma may wish to speak with their physician regarding their individual risks and benefits of different types of therapies or the participation in a clinical trial further evaluating gene expression profiling or novel therapeutic approaches for neuroblastoma. Sources of information regarding ongoing clinical trials include the National Cancer Institute (www.cancer.gov).
Reference: Asgharzadeh S, Pique-Regi R, Sposto R, et al. Prognostic Significance of Gene Expression Profiles of Metastatic Neuroblastomas Lacking MYCN Gene Amplification. Journal of the National Cancer Institute. 2006; 98:1193-1203.