Definition and Overview
Neuroblastoma is a malignant cancer formed by a certain group of nerve cells known as the neural crest. These types of cells are responsible for creating and developing tissues in the body and the nervous system.
In the normal cycle of cells, newly formed cells mature and then eventually die to give way to new cells. In case of cancer, the cells do not mature; instead they proliferate until they form tumours or masses. Some of these cancer cells can then break out, travel through the bloodstream, and latch to a tissue or blood vessel, where new tumours can form. In this case, the cancer is said to have metastasized (or spread).
Neuroblastoma creates tumours or masses that can be seen in various areas of the body such as the neck and abdomen. However, they can also be detected in the spinal cord and adrenal glands, which many experts believe to be the site of origin of most of the neuroblastoma cases. These glands, which are found above the kidneys, secrete hormones that help regulate blood pressure and heart rate, among others. From the original site, the cancer can spread to the lymph nodes, liver, kidneys, and skin.
This cancer occurs almost always in children, while in very rare instances, some adults can also be diagnosed with such.
The symptoms associated with the disease depend on the original site of the tumour. If neuroblastoma begins in the abdomen, the child may feel pain in the abdomen or suffer from abdominal cramps. If he or she is having issues with coordination and motor skills such as walking or grabbing objects, the cancer may be in the spinal cord.
Neuroblastoma is unique compared to other cancers in the sense that it sometimes goes away even without any treatment. However, since the cancer is often detected in its later stages, treatment such as surgery, chemotherapy, radiotherapy, immunotherapy, and stem cell transplant are often provided.
Who Should Undergo and Expected Results
Children who are born in families with the history of the disease may have an increased risk, although it’s rare to have a familial-oriented neuroblastoma. In the majority of cases, it is sporadic, which means it happens for unknown reasons or causes.
Neuroblastoma is often diagnosed among children who are five years old and below. Newly born babies can also develop the disease. Boys are more likely to have it than girls.
The results of the treatment depend on many factors including the age, severity of the condition, aggressiveness of the disease, and the kind of treatment provided. Children below five are more likely to recover especially if the disease is discovered in its earliest stages such as stage 1 and 2. This also means that cancer cells have not yet spread to other parts of the body.
Unfortunately, neuroblastoma cases are usually discovered in their advanced stages. They may already be more aggressive, and thus, different kinds of treatments may have to be administered to save the life of the patient.
A protein known as MYCN can play a critical role in the child’s survival. The protein is part of a gene that can mutate and become cancer. If the MYCN amplification of neuroblastoma is present, the condition may be harder to treat as the protein itself promotes the growth and spread of the cancer cells.
Some children are diagnosed with stage 4S cancer. This occurs among children below a year old. It’s not clear how it develops, but it’s often left untreated but monitored since it almost always goes away.
Some patients go through neuroblastoma only once. There are others, however, who are at risk of recurrence, particularly those who are classified as high risk.
How Does the Procedure Work?
A lump in any or several parts of the body of a child may compel parents to see their doctor for a diagnosis. To confirm neuroblastoma, a variety of tests are often conducted. These include HVA (homovanillic acid) or VMA (vanillylmandelic acid) examinations, which use urine samples.
A special kind of image scan known as MIBG (metaiodobenzyl guanidine) may also be carried out. It involves injecting MIBG into the body, allowing the neuroblastoma cells, which are responsible for the development of the condition, to absorb it. In turn, the cells appear during imaging. Biopsy, meanwhile, is a standard cancer diagnostic tool where a sample of tissue or spinal fluid is obtained to detect the presence of cancer cells.
Other tests include urinalysis, physical exam, X-ray, and other imaging tests such as CT and MRI scans.
Once the condition has been confirmed, the next step is to determine the stage of cancer. In the new method of staging, the doctor can determine the first course of action. For instance, stages 1 to 2B can still be treated with surgery, which involves removing the tumour, but advanced stages may render the technique futile.
Otherwise, surgery is followed by other forms of treatment like chemotherapy, radiation therapy, immunotherapy, and stem cell transplant.
In chemotherapy, drugs are administered to kill the cancer cells. Lately, chemotherapy has become more targeted to significantly reduce side effects and avoid harming healthy cells and tissues. Chemotherapy may also be combined with stem cell therapy in which stem cells are harvested from the bone marrow. They are then frozen and stored. The bone marrow is then destroyed by high-dose chemo. Once it’s wiped out, the stem cells are reintroduced. This technique, nevertheless, is recommended only for high-risk patients.
Possible Risks and Complications
The risks and complications can greatly vary depending on the treatment, stage of the disease, body’s immunity, and dosage provided. Surgery increases the risk of infection. Chemotherapy, meanwhile, can induce vomiting, nausea, and fever. It may also cause temporary hair loss, brittle nails, and fatigue. Radiation therapy can burn the targeted site, especially if several sessions have to be performed.
There have been reported cases where patients develop problems with their hearing fertility, and cardiovascular system. Thus, it is important for the doctors and parents of the patient to weigh the benefits and risks of every treatment to make a well-informed decision.
Dome JS, Rodriguez-Galindo C, Spunt SL, Santana VM. Pediatric solid tumours. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff's Clinical Oncology. 5th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2014:chap 95.
National Cancer Institute: PDQ neuroblastoma treatment. Bethesda, MdD: National Cancer Institute. Date last modified 9/6/2013. Available at: www.cancer.gov/cancertopics/pdq/treatment/neuroblastoma/HealthProfessional. Accessed November 26, 2014.