Treatment of Neuroblastoma by Risk Group

Treatment for neuroblastoma is largely based on which risk group a child is in. Generally, younger children with smaller tumors are in the lower risk groups, while older children, children with tumors that have spread throughout the body, and children whose tumors have unfavorable features or extra copies of the MYCN gene are in the high-risk group. Some infants with neuroblastoma that has spread throughout the body can still be considered low risk, especially if their tumor does not have extra copies of MYCN or other unfavorable features.

Low risk

Children at low risk usually don’t need very intensive treatment to cure the neuroblastoma. In fact, some children (especially young infants with small tumors) might not need to be treated at all because some of these neuroblastomas will mature or go away on their own.

If a child is low risk and the tumor can easily be removed, surgery might be the only treatment needed. Even if some neuroblastoma is left behind after surgery, the child can usually be watched carefully without further treatment because the remaining tumor will often mature or go away on its own. 

If much of the tumor can’t be removed, the tumor gets bigger after surgery, or if the tumor is causing symptoms, chemotherapy (chemo) is typically given. A common chemo regimen is a combination of carboplatin, cyclophosphamide, doxorubicin, and etoposide. But other combinations may be used.

For those few children who have symptoms from a low-risk tumor that can’t safely be treated right away with surgery, a short course of chemo might be given first. For example, if the tumor is pressing on the spinal cord or affecting breathing, chemo may be used to shrink the tumor to control the symptoms. A short course of radiation therapy might be used if the symptoms are not getting better with chemo, are life threatening, or are causing spinal cord compression.

Infants with stage 4S (MS) disease and no symptoms can often be watched carefully with no treatment, because these cancers typically mature or go away on their own. If the tumor causes problems such as an enlarged liver, which can be life-threatening for very young infants, chemo that is less intense may be used to shrink the tumor. Radiation therapy may be used if chemo doesn't shrink the liver right away.

Infants younger than 6 months with small adrenal tumors (which are assumed to be neuroblastomas) can often be watched closely with imaging tests, without needing surgery or other treatments. Many of these tumors will mature or go away on their own, but if a tumor keeps growing or is causing symptoms, surgery or chemo might be used.

Intermediate risk

Surgery is an important part of treatment for children at intermediate risk, but it is rarely enough on its own. Children are typically given 4 to 8 cycles (about 12 to 24 weeks) of chemotherapy before or after surgery. The chemo drugs used usually include carboplatin, cyclophosphamide, doxorubicin, and etoposide. If chemo is used first, surgery may then be done to remove any remaining tumor. Radiation therapy usually isn't needed unless the tumor is not responding well to chemo or if a child's symptoms from the tumor require emergency treatment.

Doctors are also studying the possibility of observing infants and young babies with no symptoms and favorable tumor features instead of treatment with surgery and/or chemotherapy. In this approach, doctors watch the tumor closely using imaging tests to make sure the tumor goes away or does not get bigger. If the tumor does gets bigger or a child has symptoms, then treatment with chemotherapy will be started. Some studies have shown promising results using this approach, and more studies are now being done.

Children at intermediate risk who need chemo are monitored closely to see how they respond after every 2 cycles (6 to 8 weeks). The total number of cycles they get depends on how well the chemo shrinks the tumor. Doctors hope that treating with chemo based on these results can allow children who have tumors that respond quickly to get less chemo.

High risk

Children at high risk require more aggressive treatment, which often includes chemotherapy, surgery, radiation, stem cell transplant, immunotherapy, and retinoid therapy. Treatment is often done in 3 phases.

Induction: The goal of this phase is to get the cancer into remission by destroying or removing as much of it as possible. Treatment usually starts with chemotherapy, using alternating regimens of several drugs (in the United States, typically cisplatin, etoposide, vincristine, cyclophosphamide, doxorubicin, and topotecan) given at higher doses than what is used for other risk groups.

Doctors are also studying the use of other treatments in this phase, such as targeted drugs for tumors with ALK gene mutations and MIBG radiotherapy for tumors that take up MIBG.

Surgery is usually done after induction to try to remove any tumors that are still visible.

Consolidation: This phase uses more intensive treatment to try to get rid of any remaining cancer cells in the body. High-dose chemotherapy is given, followed by one or two stem cell transplants. Some research has suggested that giving two stem cell transplants back to back (tandem stem cell transplants) may be better than giving one stem cell transplant. This is now being studied further in clinical trials.

Radiation is often given to the primary tumor site after a stem cell transplant (even if the tumor was removed by surgery) and to any other parts of the body that might still have cancer, based on MIBG scan results.

Maintenance: The goal of this phase of treatment is to try to lower the chance that the cancer will come back. Treatment is typically given for about 6 months after consolidation has been completed, and includes the retinoid drug 13-cis-retinoic acid (isotretinoin), as well as immunotherapy with a monoclonal antibody such as dinutuximab (Unituxin) and immune-activating cytokines (GM-CSF and IL-2). As part of this treatment, the drug eflornithine might be given for up to 2 years as well.

Recurrent neuroblastoma

If neuroblastoma comes back after initial treatment, it is known as a recurrence or relapse. Treatment of recurrent neuroblastoma depends on many factors, including the initial risk group, where the cancer recurs, and what treatments have been used.

For low- and intermediate-risk neuroblastomas that recur in the same area where they started, surgery with or without chemotherapy may be effective.

For high-risk cancers or those that recur in distant parts of the body, treatment is usually more intense, and may include a combination of chemotherapy, surgery, and radiation therapy (such as MIBG radiotherapy). Chemotherapy might include drugs that weren’t used during the initial treatment. Other options might include intensive treatment with high-dose chemotherapy followed by a stem cell transplant, or treatment with the monoclonal antibody naxitamab (Danyelza).

Because these cancers can be hard to treat, clinical trials of newer treatments, such as other monoclonal antibodies, CAR T-cell therapy, or other new anti-cancer drugs, might be another reasonable option. To learn more, see What’s New in Neuroblastoma Research?