Where does the tumor come from?
During fetal development, neural crest cells migrate throughout the body and give rise to the sympathetic nervous system, including the adrenal medulla and ganglia along the spine. If some of these cells do not complete maturation, they can develop into neuroblastoma. That is why the tumor occurs mainly in young children and is located along the sympathetic chain. In infants, immature cells sometimes mature later, and the tumor turns benign or disappears - a phenomenon that almost never occurs in other malignant tumors.
- Tumor of immature cells of the sympathetic nervous system
- Most common location: adrenal gland
- May occur along the spine, chest, neck, and pelvis
- Babies can mature independently
- Tumor behavior depends on age and molecular features
Symptoms
Manifestations depend on the location of the tumor and the presence of distant foci. With an abdominal tumor, parents often feel a dense formation themselves or notice an enlargement of the abdomen; At the same time, the child may be restless, eat poorly, and lose weight. A tumor in the chest causes coughing and shortness of breath; a tumor in the neck causes drooping of the eyelid and constriction of the pupil. Growth towards the spinal canal leads to weakness in the legs and difficulty urinating. When it spreads to the bones, pain and lameness appear, and bruising around the eyes with protrusion of the eyeballs is considered a typical sign.
- Dense formation and enlargement of the abdomen
- Pallor, lethargy, loss of appetite and weight
- Bone pain and lameness
- Bruising around the eyes and protrusion of the eyeball
- Drooping of the eyelid and constriction of the pupil
- Weakness in the legs when growing into the spinal canal
- Persistent diarrhea with hormonally active tumors
Diagnostics
They start with an ultrasound, which is accessible and safe for the child, then perform a CT or MRI to accurately assess the extent and relationship to the vessels. An important feature is that most neuroblastomas produce catecholamines, the metabolic products of which are determined in the urine, and this helps in both diagnosis and observation. The bone marrow must be examined, since the tumor often spreads into it, and a special radioisotope study is carried out to search for foci. The diagnosis is confirmed by a biopsy with molecular testing, including the status of the MYCN gene, which determines the risk group.
- Ultrasound of the abdominal cavity and retroperitoneal space
- CT or MRI of the affected area
- Catecholamines and their metabolites in urine
- LDH and ferritin
- Bone marrow puncture and biopsy
- Radioisotope study to find hotspots
- Tumor biopsy with MYCN gene testing
Risk groups and tactics
Neuroblastoma is divided into risk groups taking into account the child’s age, stage, histological structure and molecular features, primarily changes in the MYCN gene. This fundamentally affects treatment. At low risk, especially in children in the first year of life, surgery and sometimes just observation are sufficient, since the tumor can mature or regress on its own. Intermediate risk requires moderate chemotherapy and surgery. High risk is treated intensively and for a long time, combining all available methods.
- Child's age as a key factor
- Stage and extent of tumor
- Histological structure
- MYCN gene changes
- Low risk: surgery or observation
- Intermediate risk: chemotherapy and surgery
- High risk: intensive combination treatment
Treatment and observation
If the risk is low, treatment is minimal and aimed at doing no harm: in infants with small, asymptomatic tumors, close monitoring with regular ultrasound is possible. If the risk is intermediate, chemotherapy is given and the tumor is removed. High-risk treatments include intensive chemotherapy, surgery, high-dose therapy with autologous stem cell support, radiation therapy, and subsequent supportive care to kill residual cells. Observation after treatment is long-term, with monitoring of urine tests and visualization according to the schedule.
- Observation for small tumors in infants
- Surgical removal of the tumor
- Chemotherapy according to protocol
- High-dose therapy with stem cell support
- Radiation therapy at high risk
- Maintenance therapy after main treatment
- Long-term follow-up with catecholamine monitoring
