Congenital Neuroblastoma in Children

Neuroblastoma is the most common malignant neoplasm that mostly occurs in neonates. Neuroblastoma is derived from the primordial neural crest cells which eventually inhabit the sympathetic ganglia along the neural tube and the adrenal medulla.

Neuroblastoma is a malignant embryonic tumor that can arise anywhere along the migratory path of the neural crest cells.

What is Congenital Neuroblastoma?

Congenital neuroblastoma can be defined as neuroblastoma which is usually diagnosed within one month of birth. Congenital neuroblastoma can be divided into two types:

• Fetal Neuroblastoma
• Neonatal Neuroblastoma

Fetal Neuroblastoma

In the majority of cases (almost 90%), fetal neuroblastomas arise in the adrenal glands. Mostly, these types of neuroblastomas are diagnosed in the third trimester of pregnancy but they have been diagnosed as early as 19 weeks of gestation as well. The mean age of diagnosis is almost 36 weeks. These types of tumors undergo maturation and regression and have an excellent prognosis.

Neonatal Neuroblastoma

Neonatal neuroblastomas have a very good prognosis in neonates as compared to older children and almost 90% of these tumors can be cured. Only 45% cases of neonatal neuroblastomas originate from adrenal glands compared to fetal neuroblastomas.

These types of neuroblastomas are difficult to diagnose in the early stages and almost 60% of cases are diagnosed at the metastatic stages.

How Common is Congenital Neuroblastoma in Children?

• Almost 7 to 10 % of childhood cancers are related to neuroblastoma
• Almost 800 new cases are diagnosed every year in the United States
• It is found slightly more often in boys compared to girls
• Neuroblastoma accounts for 50 % of all cancers in infants
• It is the most common tumor in infants younger than 1 year
• Neuroblastoma in children is mostly diagnosed before the age of 5
• Environmental factors do not play any role in the development of neuroblastoma because the incidences of neuroblastoma is almost the same worldwide

Survival Rates of Congenital Neuroblastoma in Children

Infants with congenital neuroblastoma have better chances of survival after treatment compared to older children. The five-year survival rate of neuroblastoma in children based on the categories of risk is given below:

• Low-risk patients have a survival rate of almost 95 %
• Moderate-risk patients have a survival rate between 80 and 90 %
• High-risk patients have a survival rate of about 50 %

Diagnosis of Congenital Neuroblastoma in Children

Congenital neuroblastoma is one of the commonest malignant neoplasm found in fetuses and neonates and is the second commonest solid tumor in children, after brain tumors. The incidence of congenital neuroblastoma is almost 1 in 7000 live births. Congenital neuroblastoma results in more infant deaths compared to other cancers.

Neuroblastoma is a malignant embryonic tumor derived from the primordial neural crest cells which inhabit sympathetic ganglia along the neural tube and the adrenal medulla. Both adrenal medulla and sympathetic ganglia release catecholamines, which can be used as a biomarker for the diagnosis of congenital neuroblastoma. Another diagnostic feature of congenital neuroblastoma is the presence of paraplegia noted on neonatal examination.

Clinical Presentations of Congenital Neuroblastoma in Children

Congenital neuroblastoma has a variety of clinical presentations. Some of them may include:

• Presence of an indolent abdominal or chest mass
• Neuroblastoma tumors infiltrated into the bones can present pallor secondary to anemia, pain or a limp
• Horner’s syndrome due to rare cervical neuroblastomas
• Metastasis of neuroblastoma to the orbital bones may result in periorbital ecchymosis, proptosis, and blindness
• Spinal neuroblastomas may result in radicular pain, sensory deficits, motor deficits, and sphincteric dysfunctions

Complications of Congenital Neuroblastoma in Children

Congenital neuroblastoma is associated with a large number of complications like other tumors. For example, kidney damage due to pressure created by paraspinal mass. Surgical intervention may lead to significant spinal damage. Some other complications due to radiotherapy may include the following:

• Vomiting
• Cardiotoxicity
• Infertility
• Diarrhea
• Deafness
• Liver abnormalities
• Skeletal abnormalities
• Skin reactions
• Lethargy
• Infertility
• Secondary malignancies

Treatment of Congenital Neuroblastoma in Children

The treatment for congenital neuroblastoma in children mainly includes a combination of radiotherapy and surgical resection. Resection is mainly performed in case of low-risk tumors.

Chemotherapy is suggested for intermediate-risk tumors. It can be used before surgery as well for reducing the tumor size. High-risk tumors are often treated with a combination of both chemotherapy and surgery. Besides, bone marrow transplantation is also opted for high-risk tumors especially if the tumors are exceedingly resistant.