Neuroblastic tumours, also known as neurogenic tumours, are a group of tumours that arise from neuroblast cells (young nerve cells) and/or a specific type of chromaffin cell called paraganglia cells, which produce catecholamine hormones in nerve tissue. These tumours often develop within the sympathetic chain in the body, which consists of the bilateral nerves that run parallel to the spine from the base of the skull to the coccyx (bottom portion of the spine). The nerves in this chain are primarily responsible for the ‘fight or flight’ responses, such as sweat, reflexes and accelerated heart rate.
The nervous system is made up of two primary components: the central nervous system (CNS), and the peripheral nervous system (PNS). The CNS is made up of the brain and spinal cord, and is responsible for all sensory and motor functions in the body. The PNS encompasses all nerves outside of the CNS, and is responsible for all involuntary functions in the body. The PNS is further subdivided into the autonomic nervous system (ANS) and the somatic nervous system (SNS). The ANS controls involuntary processes and glands, such as heart rate, blood pressure, respiration, and digestion. Comparatively, the SNS is responsible for voluntary and involuntary muscle movements, as well as transmitting sensory information to the CNS.
Neuroblastic tumours are generally diagnosed equally among the sexes, and are generally diagnosed in children under 10. However, anyone can develop these diseases.
Types of Neuroblastic Tumours
There are three primary types of neuroblastic tumours, which are categorised by the types of cells they develop from.
Ganglioneuroma
Ganglioneuromas are a rare type of neuroblastic tumour that contain ganglion cells and neuronal cells without an immature blast cells. Unlike most neuroblastic tumours, ganglioneuromas tend to be slightly more common in females. These tumours are often slow-growing, non-aggressive, and can have a good prognosis.
Ganglioneuroblastoma
Ganglioneuroblastoma is a more common type of neuroblastic tumour that contains ganglion cells, neuronal cells, and immature blast cells. These tumours are often attached to a nerve trunk, which is a bundle of nerve fibres or the main stem of a nerve. These tumours can be aggressive, but can have a good prognosis when found early.
Neuroblastoma
Neuroblastomas are neuroendocrine tumours that develop from neuroblast cells (young nerve cells) in nerve tissue. Neuroblasts are most commonly found in the adrenal glands, which are located on top of the kidneys; however, they can also be found in the nerve tissues of the neck, chest, abdomen or pelvis. For more information on neuroblastomas, please refer to the Rare Cancers Australia Neuroblastoma page.
Treatment
If a neuroblastic tumour is detected, it will be staged and graded based on size, metastasis (whether the cancer has spread to other parts of the body) and how the cancer cells look under the microscope. Staging and grading helps your doctors determine the best treatment for you.
Cancers can be staged using the TNM staging system:
- T (tumour) indicates the size and depth of the tumour.
- N (nodes) indicates whether the cancer has spread to nearby lymph nodes.
- M (metastasis) indicates whether the cancer has spread to other parts of the body.
This system can also be used in combination with a numerical value, from stage 0-IV:
- Stage 0: this stage describes cancer cells in the place of origin (or ‘in situ’) that have not spread to nearby tissue.
- Stage I: cancer cells have begun to spread to nearby tissue. It is not deeply embedded into nearby tissue and had not spread to lymph nodes. This stage is also known as early-stage cancer.
- Stage II: cancer cells have grown deeper into nearby tissue. Lymph nodes may or may not be affected. This is also known as localised cancer.
- Stage III: the cancer has become larger and has grown deeper into nearby tissue. Lymph nodes are generally affected at this stage. This is also known as localised cancer.
- Stage IV: the cancer has spread to other tissues and organs in the body. This is also known as advanced or metastatic cancer.
Cancers can also be graded based on the rate of growth and how likely they are to spread:
- Grade I: cancer cells present as slightly abnormal and are usually slow growing. This is also known as a low-grade tumour.
- Grade II: cancer cells present as abnormal and grow faster than grade-I tumours. This is also known as an intermediate-grade tumour.
- Grade III: cancer cells present as very abnormal and grow quickly. This is also known as a high-grade tumour.
Once your tumour has been staged and graded, your doctor may recommend genetic testing, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.
Treatment is dependent on several factors, including location, age, stage of disease and overall health.
Treatment for neuroblastic tumours may include:
- Surgery to remove as much of the tumour as possible.
- Radiation therapy.
- Chemotherapy.
- Stem-cell transplants.
- Immunotherapies.
- Clinical trials.
- Palliative care.
For more information on the treatment options, please refer to the Rare Cancers Australia treatment options page.
Risk factors
While the cause of neuroblastic tumours remain unknown, the following factors may increase the likelihood of developing the disease:
- A family history of ganglioneuromas, ganglioneuroblastomas and/or neuroblastomas.
- Certain genetic conditions, such as:
Not everyone with these risk factors will develop the disease, and some people who have the disease may have none of these risk factors. See your general practitioner (GP) if you are concerned.
Early symptoms
Neuroblastic tumours may present as asymptomatic during the early stages of disease. As the tumour progresses, some of the following symptoms may appear:
- Lump or swelling in the affected area.
- Abdominal pain.
- Unexplained weight loss/loss of appetite.
- Issues urinating and/or with bowel movements.
- Exophthalmos (bulging eyes).
- Dark circles around the eyes.
- Uncontrolled eye movements.
- Bone and/or other unexplained pain.
- General weakness or paralysis.
- Difficulties breathing and/or swallowing.
- Diarrhoea.
- High blood pressure.
- Rapid heartbeat.
- Unexplainable sweating.
- Flushing of the skin.
- Blood in the urine.
Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.
Diagnosis/diagnosing
If your doctor suspects you have a neuroblastic tumour, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment.
Physical examination
Your doctor will collect your overall medical history, as well as your current symptoms. Following this, they may examine your body to check for any abnormalities.
Imaging & blood tests
The doctor will take images of your body using magnetic resonance imaging (MRI), a computed tomography scan (CT scan), x-ray, bone scan, metaiodobenzylguanidine (MIBG) scan and/or positron emission tomography (PET scan), depending on where it is suspected the cancer is. The doctor may also look at other parts of the body and look for signs of metastasis. Additionally, a blood and urine test may also be taken to assess your overall health and help guide treatment decisions.
Biopsy
Once the location(s) of the cancer has been identified, the doctor will perform a biopsy to remove a section of tissue using a needle. In most cases, this will be done by a bone marrow aspiration and biopsy. This process involves inserting the needle into the hipbone (or the breastbone in some cases) to remove samples of solid and liquid bone marrow. These samples will then be analysed for cancer cells.
Prognosis (Certain factors affect the prognosis and treatment options)
While it is not possible to predict the exact course of the disease, your doctor will be able to give you a general idea based on stage, rate/depth of tumour growth, susceptibility to treatment, age, overall fitness, and medical history. Generally, early-stage neuroblastic tumours have good prognosis and survival rates. However, if the cancer is advanced and has spread, the prognosis is not as good and there is a higher risk of cancer recurrence.
References
Some references are to overseas websites. There may be references to drugs and clinical trials that are not available here in Australia.