Staging of disease
There are two main staging systems for neuroblastoma -:
- International Neuroblastoma Staging system (INSS), which is a similar staging system to that used in other cancers, with stages 1-4 (and then a special 4S).
- International Neuroblastoma Risk Group Staging System (INRGSS) is a more recently introduced staging system that describes whether the patient has a tumour which can be removed by surgery only (L1) or whether the patient needs chemotherapy initially (L2), as well as having more distant disease (M or MS).
The table below shows details of how patients are staged within the two systems. The two staging systems are different and there is now a gradual move from the old INSS system to the newer INRGSS. INSS stage was previously assigned after surgery but the newer INRGSS tries to determine on CT and MRI appearances which tumours should be resected and which should be biopsied based on surgical risk factors. Therefore stage 1 and 2 tumours by INSS do not necessarily correlate directly with L1 tumours on INRGSS.
Staging terms used in the INSS and INGRSS staging system classifications for risk stratification in neuroblastoma
| INSS Stage | INRGSS Stage |
|---|---|
Stages 1 and 2 Stage 1: The tumour is localised and can be completely removed with surgery. Stage 2: The tumour has not spread and is on only one side of the body but cannot be completely removed by surgery because of its size or position. Stage 2A: No lymph node spread. Stage 2B: Lymph node spread is present. |
Stage L1 L1: Surgical removal looks straightforward. |
Stage 3 Stage 3: The tumour has spread to nearby organs close to where it started. Lymph nodes may or may not be involved. |
Stage L2 Stage L2: Surgery is possible but difficult i.e. there are ‘surgical risk factors’ present. |
Stage 4 Stage 4: The cancer has spread to other parts of the body that are some distance from the primary tumour |
Stage M Stage M: The cancer has spread to other parts of the body that are some distance from the primary tumour |
Stage 4S Stage 4S: This is a special case and has a better outlook than other stages. It means the child is under 12 months old and has neuroblastoma that has spread to the liver or skin but not the bones. Less than 10% of the bone marrow cells are cancer cells. Some of these children may not need any treatment because the cancer can disappear or ‘regress’ on its own. |
Stage MS Stage MS: This is a special case and has a better outlook than other stages. It means the child is under 12 months old and has neuroblastoma that has spread to the liver or skin but not the bones. Less than 10% of the bone marrow cells are cancer cells. Some of these children may not need any treatment because the cancer can disappear or ‘regress’ on its own. |
