Neuroblastoma

Neuroblastoma is a type of cancer that develops from immature nerve cells found in several areas of the body, most commonly in and around the adrenal glands, which have similar origins to nerve cells and sit atop the kidneys.

Causes and Risk Factors

The exact cause of neuroblastoma is not well understood. However, it is believed that genetic mutations play a significant role in its development. These mutations can occur spontaneously or be inherited. Certain genetic conditions, such as neurofibromatosis type 1, can increase the risk of developing neuroblastoma.

Symptoms

The symptoms of neuroblastoma vary depending on the location and size of the tumor. Common symptoms include:

• A lump or swelling in the abdomen, neck, or chest
• Weight loss
• Fatigue
• Pain in the bones, especially if the cancer has spread
• Difficulty walking or balance problems if the tumor presses on the spinal cord
• Proptosis (bulging of the eyes) or periorbital bruising if the tumor is behind the eye
• High blood pressure if the tumor compresses the renal vessels

Diagnosis

Diagnosing neuroblastoma typically involves a combination of imaging tests, such as:

• X-rays
• Computed Tomography (CT) scans
• Magnetic Resonance Imaging (MRI)
• Metaiodobenzylguanidine (MIBG) scan, which is particularly useful for neuroblastoma as the tumor cells absorb this radioactive compound
• Bone marrow biopsy to check if the cancer has spread to the bone marrow
• Urine tests to look for certain chemicals that might be produced by the tumor, such as vanillylmandelic acid (VMA) and homovanillic acid (HVA)

A definitive diagnosis is usually made through a biopsy of the tumor.

Treatment

The treatment of neuroblastoma depends on the stage of the disease, the age of the patient, and whether there are any high-risk features. Treatment options may include:

• Surgery to remove as much of the tumor as possible
• Chemotherapy to kill cancer cells that have spread
• Radiation therapy to target and destroy cancer cells in specific areas
• High-dose chemotherapy followed by stem cell rescue for high-risk disease, where the patient's own stem cells are collected before chemotherapy and then reinfused afterward to help the bone marrow recover
• Immunotherapy, such as with dinutuximab, which targets the GD2 antigen found on neuroblastoma cells
• Differentiation therapy with isotretinoin for patients with high-risk disease in first remission

Prognosis and Stages

The prognosis of neuroblastoma varies significantly depending on the age at diagnosis, stage of the disease, and biological characteristics of the tumor. Infants and young children tend to have a better prognosis than older children or adults. The stages of neuroblastoma are defined based on the extent of the tumor:

• Stage 1: The tumor is localized and can be completely removed by surgery.
• Stage 2: The tumor is localized but cannot be completely removed by surgery.
• Stage 3: The tumor has spread across the midline of the body or is incompletely resected.
• Stage 4: The tumor has spread to distant parts of the body, such as bone, bone marrow, liver, skin, and/or other organs.
• Stage 4S (also known as special): This stage applies to infants less than one year old with a primary tumor on one side of the body that has spread to the liver, skin, and/or bone marrow but not to the bones. Despite widespread disease, these children often have a favorable prognosis.

Research and Future Directions

Ongoing research is focused on improving our understanding of neuroblastoma biology, developing more effective treatments with fewer side effects, and identifying genetic markers that can predict the risk of developing aggressive disease. This includes studies on targeted therapies, immunotherapies, and combination regimens aimed at reducing toxicity while maintaining or improving efficacy.

Frequently Asked Questions (FAQs)

What is Neuroblastoma?
A type of cancer that develops in nerve tissue.

Where does Neuroblastoma typically occur?
In the adrenal glands or near the spine.

What age group is most commonly affected by Neuroblastoma?
Children under 5 years old.

What are the common symptoms of Neuroblastoma?
Lump or swelling, fatigue, weight loss, and pain.

How is Neuroblastoma diagnosed?
Through imaging tests, biopsy, and blood tests.

What are the stages of Neuroblastoma?
Stages 1-4, with Stage 4 being the most severe.

What are the treatment options for Neuroblastoma?
Surgery, chemotherapy, radiation therapy, and immunotherapy.

Is Neuroblastoma inherited?
Most cases are not inherited, but some may be genetic.

What is the prognosis for Neuroblastoma?
Varies depending on stage, age, and response to treatment.

Can Neuroblastoma be cured?
Yes, with treatment, especially if caught in early stages.