Staging
Staging is a process that tells the doctor if the cancer has spread, and if it has, how far and what organs are affected. Cancer can spread through tissue by growing into nearby areas, through the lymphatic system or the bloodstream. When cancer cells have spread to other parts of the body, it is called metastasis. Staging is an important step in treatment planning. The same procedures used for diagnosis, are used for staging of neuroblastoma. There are approximately 20 characteristics of neuroblastoma tumors on imaging that are considered Image Defined Risk Factors (IDRFs).
Risk Groups Of Neuroblastoma
Doctors divide neuroblastoma into different risk groups (low-intermediate- and high-risk) based on age, stage and specific characteristics of the tumor cells. This helps to determine the treatment options, and prognosis, or chance of curing the disease. High-risk neuroblastoma may be difficult to cure, while low-and intermediate-risk are more likely to be cured.
Doctors use the following prognostic factors to determine the risk group:
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Age of the child at diagnosis
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Stage of the tumor
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Completeness of surgical removal in L1 patients.
When the tumor is completely removed, this is called a gross total resection (GTR).
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Histology
Histology describes how the tumor cells look under a microscope. Tumors with a favorable histology have more normal looking cells; tumors with an unfavorable histology look less like normal cells and divide rapidly.
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DNA Ploidy
DNA ploidy describes the amount of DNA in a cell. Neuroblastoma cells with a normal amount of DNA are called diploid. Cells with too much DNA are hyperdiploid.
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MYCN Gene amplification
MYCN is a gene that helps control cell growth. Neuroblastoma with amplification of this gene (more than 10 copies) grow more rapidly and respond poorly to treatment.
