Chromosomal and molecular markers
Over the last 2 decades, many chromosomal and molecular abnormalities have been identified in patients with neuroblastoma. These biologic markers have been evaluated to determine their value in assigning prognosis, and some of these have been incorporated into the strategies used for risk assignment.
The most important of these biologic markers is MYCN. MYCN is an oncogene that is overexpressed in approximately one quarter of cases of neuroblastoma via the amplification of the distal arm of chromosome 2. This gene is amplified in approximately 25% of de novo cases and is more common in patients with advanced-stage disease. Patients whose tumors have MYCN amplification tend to have rapid tumor progression and poor prognosis, even in the setting of other favorable factors such as low-stage disease or 4S disease.