Neuroblastoma diagnosis, treatment, complications, and further management. The main contents of this review have been accessed from MedScape. Please do not reprint or copy this material without permission from the copyright owner.

1. NEUROBLASTOMA
LYNDON WOYTUCK
MBBS4 PROGRAMME AT ST GEORGE’S UNIVERSITY OF LONDON
DELIVERED BY THE UNIVERSITY OF NICOSIA
SHEBA MEDICAL CENTER AT TEL HASHOMER

2. CELLULAR
• Neuroblasts are pluripotent stem
cells of the nervous system
• These cells migrate along the
neuraxis to populate various sites,
with tumours presenting in adrenal
medulla (40%), paraspinal ganglia
(25%), thoracic (15%), pelvic (5%),
cervical (3%), and miscellaneous
(12%)
• Neural crest tumours can be
classified as neuroblastoma,
ganglioneuroblastoma, and
ganglioneuroma, depending on the
degree of maturation and
differentiation of the tumour.
Histology: Top right - neuroblastoma: A
monotonous population of hyperchromatic
cells with scant cytoplasm. Bottom left -
ganglioneuroblastoma: Increased schwannian
stroma. Bottom right - ganglioneuroma:
Mature ganglion cell with schwannian stroma.

3. GENETIC
• MYCN oncogene is overexpressed via amplification of the distal arm
of chromosome 2 in approximately 25% of de novo cases and is more
common in patients with advanced-stage disease, with rapid tumor
progression and poor prognosis
• Short arm deletions of chromosome 1 are the most common
chromosomal abnormality present in neuroblastoma and confer a
poor prognosis. The 1p chromosome region likely harbours tumor
suppressor genes or genes that control neuroblast differentiation
• hyperdiploidy (DNA index >1) has a good therapeutic response to
cyclophosphamide and doxorubicin, with better prognosis

4. PROGNOSIS AT PRESENTATION
• Infants more commonly present with thoracic and cervical tumors, whereas older children
more frequently have abdominal tumors.
• ~70-80% of patients >18 months present with metastatic disease
• lymph nodes, liver, bone, and bone marrow
• Patients with localized tumours have an 80-90% 3-year event-free survival [EFS] rate
• <50% with metastasis are cured, even with the use of high-dose therapy followed by
autologous bone marrow or stem cell rescue.
• Generally, >50% of patients present with metastatic disease at the time of diagnosis, 20-
25% have localized disease, 15% have regional extension, and approximately 7% present
during infancy with disseminated disease limited to the skin, liver, and bone marrow
(stage 4S).
• The 3-year EFS for high-risk patients, those with disseminated disease, treated with
conventional chemotherapy, radiation therapy, and surgery is less than 20%.
• Differentiating agents and dose intensification of active drugs, followed by autologous bone marrow
transplant, have been reported to improve the outcome for these patients, contributing to an EFS of
38%. A single-arm study of tandem stem cell transplantation: 3-year EFS of 58%, with other ongoing
randomized studies

5. EPIDEMIOLOGY
• 7.8% of childhood cancers in the United States
• Incidence ~9.5 cases per million children (highest among high income countries)
• Incidence white>black children
• Sex: male-to-female ratio 1.2:1.
• Age: Incidence decreases every consecutive year up to age 10 years, after which
the disease is rare
• The survival rate 5 years from diagnosis is approximately 83% for infants, 55%
for children aged 1-5 years, and 40% for children older than 5 years
• 40% of patients are at <1year, 35% at 1-2 years, and 25% >2 years old when
diagnosed.

6. PRESENTATION
• Pain or palpable mass
• May present with abdominal distension
• Other symptoms dependent on local mass effect
• emesis, weight loss, anorexia, fatigue, and bone pain. Hypertension is an uncommon sign of the disease and is
generally caused by renal artery compression, not catecholamine excess. Chronic diarrhea is a rare presenting
symptom secondary to tumor secretion of vasoactive intestinal peptide secretion. bone pain and a limp. However,
patients may also present with unexplained fever, weight loss, irritability, and periorbital ecchymosis secondary to
metastatic disease to the orbits. The presence of bone metastases can lead to pathologic fractures. neurologic
symptoms, including weakness, limping, paralysis, and even bladder and bowel dysfunction. mild airway obstruction
or chronic cough Horner syndrome metastatic disease confined to the liver, skin, and bone marrow (stage 4S). If this
type of tumor develops in neonates, skin lesions may be confused with congenital rubella, and, if the patient has
severe skin involvement, the term "blueberry muffin baby" may be used.
• Approximately 2% of patients present with opsoclonus and myoclonus a paraneoplastic syndrome characterized by
the presence of myoclonic jerking and random eye movements. These patients often have localized disease and a
good long-term prognosis. Unfortunately, the neurologic abnormalities can persist or progress and can be
devastating.
• Finally, intractable diarrhea is a rare paraneoplastic symptom and is associated with more differentiated tumors and a
good prognosis.

7. EXAMINATION
• Children are usually referred to a pediatric oncologist by primary care providers who have
identified a persistent unexplained symptom or sign, either upon physical examination or
based on screening test findings.
• In patients with suspected neuroblastoma, performing a thorough examination with
careful attention to vital signs (eg, blood pressure), neck, chest, abdomen, skin, and
nervous system is essential.
• Metastatic lesions of the skin are common in infants younger than 6 months and may
represent stage 4S disease.
• Examination of the abdomen may reveal an abdominal mass, leading to the appropriate
workup.
• Neurologic examination may reveal Horner syndrome. In the case of dumbbell tumors,
compression of the spinal cord may produce lower extremity weakness or paraplegia.
Patients with neurologic involvement by tumor should be treated emergently, secondary
to the risk of permanent neurologic sequelae.

8. DIFFERENTIAL
• For an intra-thoracic neuroblastoma consider:
• intrathoracic lymphoma
• extra lobar pulmonary sequestration
• round pneumonia
• ganglioneuroma
• ganglioneuroblastoma
• For an intra-abdominal neuroblastoma consider:
• ganglioneuroma
• ganglioneuroblastoma
• rhabdomyosarcoma
• Wilms tumour

9. INVESTIGATION
• CBC count and differential (Anemia or other cytopenias suggest bone marrow involvement.)
• Urine collection for catecholamines (VMA/HVA) and UAA single sample or collected urine test for
VMA/HVA is highly accurate in CLIA approved laboratories. Centers usually send samples to a
specialty laboratory and/or perform a timed collection of urine.
• A urinary catecholamine level is considered to be elevated if it is 3 standard deviations higher than
the age-related reference range levels.
• Serum creatinine
• Liver function tests
• Electrolytes
• Calcium, Magnesium, Phosphorus, Uric acid;
• Serum lactate dehydrogenase (LDH); Ferritin; Thyroid-stimulating hormone (TSH), T4;
Immunoglobulin (Ig)G levels

10. INVESTIGATION
• Xray: typically demonstrating an intrathoracic or intraabdominal soft-tissue mass. Pressure on
adjacent bones may cause remodelling of ribs, vertebral bodies or pedicle thinning. Up to 30% may
have evidence of calcification on the plain film. Skeletal metastases usually ill-defined and lucent,
with periosteal reaction or metaphyseal lucency.
• Ultrasound: Neuroblastoma on ultrasound demonstrates a heterogeneous mass with internal
vascularity. Often there are areas of necrosis that appear as regions of low echogenicity. Calcification
may or may not be evident on ultrasound
• CT:tumour typically is heterogeneous with calcifications seen in 80-90% of cases2. Areas of necrosis
are of low attenuation. May usually displace tissues or invade. Commonly lymph node enlargement
• MRI: superior to all other modalities in assessing the organ of origin, intracranial or intraspinal
disease and bone marrow disease
• MIBG (metaiodobenzylguanidine labeled to Iodine123) 95% of neuroblastomas secrete catecholamines,
however, 30% of neuroblastomas are negative on MIBG: sensitivity: 88%, specificity: 99% (for
sympathetic tissue)

11. MANAGEMENT
• Medical: Cooperative Group Treatment Strategies – Low, intermediate and high risk stratification: Vincristine, cyclophosphamide, and
doxorubicin
• Carboplatin and etoposide
• Cisplatin and etoposide
• Ifosfamide and etoposide
• Cyclophosphamide and topotecan
• Consolidation regimens used in neuroblastoma include the following:
• Carboplatin and etoposide with melphalan or cyclophosphamide
• Thiotepa and cyclophosphamide
• Melphalan and total body irradiation
• In Europe, several studies have used busulfan with melphalan or cyclophosphamide. One commonly used salvage or relapse therapy
regimen is the combination of topotecan and cyclophosphamide. The use or retinoids have been incorporated in maintenance regimens in
the posttransplant setting. Irinotecan is also under investigation.
• Surgical: Surgical resection plays an important role in the treatment of patients with neuroblastoma. For patients with localized disease,
surgical resection is curative. For patients with regional or metastatic disease, surgery to establish a diagnosis and obtain adequate
samples for biologic studies is essential. Typically, second-look surgery postchemotherapy is used to attempt a complete resection. The
emphasis in the second-look procedure is as complete a debulking as possible without sacrificing major organ function. Patients with
residual disease postchemotherapy and surgery may benefit from the use of radiotherapy.

12. FOLLOW UP CARE

13. REFERENCES
• Radiopaedia. Neuroblastoma. Accessed from:
http://radiopaedia.org/articles/neuroblastoma
• Medscape. Pediatric Neuroblastoma. Accessed from:
http://emedicine.medscape.com/article/988284-overview