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Background: There is an international consensus that evaluation of MYCNamplification should be done in all cases of newly diagnosed neuroblastoma. MYCN is the most important prognostic factor for neuroblastoma and determines treatment strategy.
Materials and methods: In this study we evaluated paraffin embedded tissue block and bone marrow aspiration of 75 neuroblastoma patients with mean age of 4.1 years, including 32 female and 43 male, by conventional and also real time quantitative PCR.
Results: Forty eight and 43 percent were MYCN amplification positive by Real time and conventional PCR, respectively. 28% of patients less than one year old and 48% of patients older than one year showed MYCN amplification.50 percent of cases with pathological diagnosis of small round cell tumor had MYCN amplification.
Conclusion: PCR is a fast, reliable and cost effective method for the evaluation of MYCN amplification and can be performed using DNA extracted from small tissue samples and paraffin embedded blocks. As expected regarding detection power and convenience, Real time PCR was superior to conventional PCR.