Update Course Rewind: Staging and Management of Neuroblastoma 2022

The Case

A 16-month-old presented with a right adrenal mass measuring 8 centimeters 0:00. Biopsy revealed favorable-cell neuroblastoma biology with no MYCN amplification but with segmental chromosomal abnormalities 0:00. The question was how to risk-stratify this tumor 0:00 0:00.

The Decision Point

For years, MYCN amplification has been the dominant molecular marker driving neuroblastoma risk stratification 0:24. Its absence typically signals lower-risk disease 0:24. But this tumor carried segmental chromosomal aberrations — losses or gains of portions of chromosomal arms — and the significance of those findings in the absence of MYCN amplification was evolving 0:00 0:24.

The Children's Oncology Group neuroblastoma classification tree is constantly changing as new information is added 0:24. Between the time many surgeons completed training and this case presented, the evidence base had shifted 0:24. COG reviewed patients enrolled in trials between 2007 and 2017 0:24 and found that the presence of segmental chromosomal aberrations such as loss or gain of a portion of the chromosomal arm can have a negative impact on patient outcomes 0:24. The question was whether this patient's tumor, lacking MYCN amplification but carrying segmental abnormalities, should be treated as intermediate-risk or escalated to high-risk therapy 0:24 0:24.

What the Team Did

Based on the 2021 COG classification, the tumor was classified as higher risk 0:24. The updated schema classifies tumors as high risk when there is no MYCN amplification but segmental chromosomal abnormalities are present 0:24. This represented a meaningful change in approach — a tumor that might have been managed with less intensive therapy under older schemas now warranted high-risk protocols 0:24 0:24.

What This Changes

The case illustrates how molecular profiling continues to refine neuroblastoma risk stratification beyond the traditional markers 0:24 0:24. MYCN status remains critical, but it is no longer sufficient 0:24 0:24. Segmental chromosomal aberrations — detectable on array comparative genomic hybridization or next-generation sequencing panels — now carry independent prognostic weight 0:24 0:24.

For surgeons, this means two things 0:00 0:24. First, biopsy tissue must be adequate for comprehensive molecular analysis, not just histology and MYCN testing 0:00. Second, risk classification at the time of diagnosis may differ from what the same tumor would have received even a few years earlier 0:24 0:24. The treatment plan follows the classification, so understanding the current schema matters for informed consent and for anticipating the intensity of therapy a family will face 0:24 0:24.

The outcome of this specific case was not discussed. What was discussed was the framework: favorable histology and absent MYCN amplification are no longer enough to call a tumor lower-risk if segmental chromosomal abnormalities are present 0:00 0:24. That distinction now determines whether a child receives intermediate-risk or high-risk chemotherapy, and whether the surgical approach is primary resection or delayed resection after induction 0:24 0:24. The biology drives the strategy, and the biology we can detect keeps expanding 0:24 0:24.