Diagnosing Neuroblastoma

Oncologists at Hassenfeld Children’s Hospital at NYU Langone are experienced in diagnosing neuroblastoma, a rare cancer of the sympathetic nervous system—the network of nerves that helps control the response to stress in organs and structures such as the intestines, smooth muscle, heart, and glands. Most neuroblastoma tumors are diagnosed in children under age five, with about a third found in infants.

A neuroblastoma tumor arises in early forms of nerve cells that develop before a child is born. It frequently begins in the nerve tissue of the adrenal glands, which are located on top of each kidney and produce hormones that regulate blood pressure, blood sugar, and heart rate. A tumor can also form in other parts of the abdomen, chest, neck, or spinal cord.

Children under the age of 18 months tend to have less aggressive neuroblastomas. Children over 18 months may develop a more aggressive cancer, which can spread beyond its original location. As many as 70 percent of children with neuroblastoma have advanced cancer that has spread to other organs at the time of diagnosis.

Neuroblastoma tumors can occur in numerous areas of the body, including the abdomen, bones, chest, neck, and lymph nodes. As a result, symptoms can vary. They typically occur when a tumor presses on bone, organs, or tissue. Symptoms include swelling of the abdomen, chest, face or legs; problems with breathing, bowel movements, or urination; a painless lump in the abdomen or neck; and unexplained weight loss. Tumors that press on the spinal cord can cause neck and back pain and paralysis.

Very rarely, neuroblastomas go away on their own, though doctors don’t know why. These neuroblastomas almost always occur during infancy.

Neuroblastoma may be diagnosed after the cancer has spread to the bones, bone marrow, liver, or a combination of these areas. Tumors that have spread require more aggressive treatment than those that haven’t. How the cancer cells appear under a microscope—called histology—and changes in the genes that make up the cells also help determine the kind of treatment needed.

Diagnostic Tests

To diagnose a neuroblastoma, our oncologists ask about your child’s medical history and perform a variety of tests. Because children with neuroblastomas tend to be very young, sedation may be used for tests that take longer than a few minutes or require the child to lie still.

Physical Exam

Your child’s doctor examines him or her for lumps under the skin, swelling in the legs or abdomen, enlarged lymph nodes, and abnormal masses or growths. He or she also evaluates the movement and strength of the arms and legs, which can be affected by a tumor pressing on the spinal cord.

Blood and Urine Tests

The doctor orders blood or urine tests for levels of catecholamines, hormones produced in the adrenal glands that are released during times of stress. They enter the blood and pass through urine. Neuroblastoma cells can sometimes make these hormones as well.

Other blood tests check how the kidneys and liver are functioning. Neuroblastoma can cause problems with the blood, such as anemia, when the body doesn’t produce enough healthy red blood cells. Your child’s doctor orders a complete blood count, or CBC, which reveals the levels of white blood cells, which fight infection; red blood cells, which carry oxygen throughout the body; and platelets, which help the blood clot.

Ultrasound

An ultrasound uses sound waves to create images of the abdominal organs and tissue. It can locate tumors and determine their size.

CT Scan

CT scans can reveal whether the cancer has spread to other parts of the body, such as the neck, chest, or abdomen. A CT scan uses X-rays and a computer to create three-dimensional images of the organs and tissues, as well as tumors.

MRI Scan

MRI uses magnetic fields and radio waves to create images of the soft tissues in the body. An MRI is particularly useful in determining if a tumor is pressing on the spinal cord, because it can distinguish between a tumor and bone. This provides information about any damage to the spinal cord.

Thirty minutes before the test, a technician injects a contrast agent or dye into a vein to highlight tumors during the scan.

MIBG Scan

In this nuclear imaging test, a radioactive tracer is injected into a vein to help locate and diagnose neuroblastoma tumors. The tracer helps identify MIBG, a substance that tends to gather in neuroblastomas. Using sedation, a doctor injects the tracer into a vein. One to three days later, a scan is performed to identify bright spots on the scan, which may indicate cancer cells.

Bone Marrow Aspiration and Biopsy

A bone marrow aspiration and biopsy may be performed to determine if cancer has spread to the bone marrow. Using sedation, the doctor advances a small, hollow needle into the hipbone to remove a small amount of marrow and a tiny sample of bone for analysis under a microscope. Pain medication is given for a day or two after the test to relieve soreness at the injection site.

If urine and bone marrow tests show signs of neuroblastoma, your doctor may confirm the diagnosis of neuroblastoma without further testing.

Surgical Biopsy

If urine and bone marrow tests don’t provide a definitive diagnosis, a surgeon performs a biopsy. In this procedure, which is done in the hospital with general anesthesia, the doctor makes a small opening in the body near the tumor and removes all or part of the tumor. The tumor or sample is sent to a laboratory for analysis.