Prognostic Factors : MYCN Amplification

Amplification (greater than 10 copies per dipoloid genome) of MYCN oncogene on chromosome 2p24 is seen in about 25% of neuroblastomas and predicts poor prognosis. It is associated with deletion of 1p and gain of 17q. The morphologic correlate of MYCN amplification is undifferentiated or poorly differentiated histology, a high mitotic-karyorrhectic index, and prominent nucleoli. Patients with MYCN amplification show rapid tumor progression. It can be detected by PCR, FISH (shown here), or by immunohistochemistry. The MYCN status of a given tumor remains unchanged after chemotherapy. This FISH image of neuroblastic tumor cells displaying MYCN gene status (green signal) shows amplification in the tumor cells in the left panel. The control panel on the right shows normal diploid signals. Image modified from: Copy number gain of MYCN gene is a recurrent genetic aberration in Chinese pediatric neuroblastoma patients Authors: Miao Wang, Chunju Zhou, Rongqin Cai, Yong Li and Liping Gong. Diagnostic Pathology 2013, 8:5; Used in accordance with Creative Commons License 2.0