Ganglioneuroma overview

# Overview
Ganglioneuroma is a rare and benign tumor of the peripheral nervous system that tends to affect children and young adults. Ganglioneuroma may be classified into two subtypes/groups: Ganglioneuroma-maturing and ganglioneuroma-mature. Ganglioneuromas are derived from the primordial neural crest cells, which are undifferentiated cells of the sympathetic nervous system. On gross pathology, ganglioneuromas are characterized by solid, white, firm, well-circumscribed, and nodular tumors. On microscopic histopathological analysis, ganglioneuromas are characterized by spindle-shaped cells with cell borders in a fibrillar matrix containing ganglion cells with large round nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm. Ganglioglioma must be differentiated from neuroblastoma, ganglioneuroblastoma, spinal schwannoma, spinal neurofibroma, adrenal adenoma, adrenal carcinoma, and pheochromocytoma. Females are more commonly affected with ganglioneuroma than males. Common complications of ganglioneuroma include paralysis, metastases, and local recurrence. The prognosis of ganglioneuroma is excellent with treatment. Symptoms of ganglioneuroma include dyspnea, chest pain, abdominal pain, bloating, pain and numbness in limbs, paresis, diarrhea, diaphoresis, and hirsuitism. Common physical examination findings of ganglioneuroma include dyspnea, stridor, motor loss, sensory loss, diaphoresis, scoliosis, clitoromegaly, hirsuitism, and hypertension. On chest x-ray, ganglioneuroma is characterized by a posterior mediastinal mass, which may cause rib spreading and foraminal erosion. On CT scan, ganglioneuroma is characterized by a solid, well-circumscribed, and encapsulated mass that is iso to hypoattenuating to muscle. On MRI scan, ganglioneuroma is characterized by a well circumscribed and encapsulatated mass with low signal intensity on T1-weighted images and intermediate to high signal intensity on T2-weighted images. Surgery is the mainstay of treatment for symptomatic ganglioneuroma. Adjunctive chemotherapy and radiotherapy may be required.

# Classification
According to International Neuroblastoma Pathology Classification (INPC), ganglioneuroma may be classified into two groups: Ganglioneuroma-maturing and ganglioneuroma-mature.

# Pathophysiology
Ganglioneuromas are derived from the primordial neural crest cells, which are undifferentiated cells of the sympathetic nervous system. Genes involved in the pathogenesis of ganglioneuroma include MYCN oncogene and chromosome 1p36. On gross pathology, ganglioneuromas are characterized by solid, white, firm, well-circumscribed, and nodular tumors. On microscopic histopathological analysis, ganglioneuromas are characterized by spindle-shaped cells with cell borders in a fibrillar matrix containing ganglion cells with large round nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm.

# Causes
There are no established causes for ganglioneuroma.

# Differentiating brain tumors from other diseases
Ganglioglioma must be differentiated from neuroblastoma, ganglioneuroblastoma, spinal schwannoma, spinal neurofibroma, adrenal adenoma, adrenal carcinoma, and pheochromocytoma.

# Epidemiology and Demographics
The incidence of ganglioneuroma is approximately 1 per 100,000 children in the United States. Ganglioneuroma is a rare disease that tends to affect children and young adults. Females are more commonly affected with ganglioneuroma than males. There is no racial predilection to ganglioneuroma.

# Risk factors
There are no established risk factors for ganglioneuroma.

# Screening
Screening for ganglioneuroma is not recommended.

# Natural History, Complications and Prognosis
Common complications of ganglioneuroma include paralysis, metastases, and local recurrence. The prognosis of ganglioneuroma is excellent with treatment.

# Staging
According to the International Neuroblastoma Staging System (INSS), there are six stages of ganglioneuroma based on clinical, radiologic, and surgical features.

# History and Symptoms
Symptoms of ganglioneuroma include dyspnea, chest pain, abdominal pain, bloating, pain and numbness in limbs, paresis, diarrhea, diaphoresis, and hirsuitism.

# Physical examination
Common physical examination findings of ganglioneuroma include dyspnea, stridor, motor loss, sensory loss, diaphoresis, scoliosis, clitoromegaly, hirsuitism, and hypertension.

# Laboratory Findings
Some patients with ganglioneuroma may have elevated concentrations of VMA (vanillylmandelic acid) or HVA (homovanillic acid) in urine.

# X Ray
On chest x-ray, ganglioneuroma is characterized by a posterior mediastinal mass, which may cause rib spreading and foraminal erosion. Plain x-rays may show a mass in the retroperitoneum, pelvis, or neck indicating the presence of metastasis.

# CT
Chest, abdomen, and pelvic CT scan may be helpful in the diagnosis of ganglioneuroma. Findings on CT scan suggestive of ganglioneuroma include a solid, well-circumscribed, and encapsulated mass that is iso to hypoattenuating to muscle.

# MRI
Chest and abdominal MRI scan may be helpful in the diagnosis of ganglioneuroma. On MRI scan, ganglioneuroma is characterized by a well circumscribed and encapsulatated mass with low signal intensity on T1-weighted images and intermediate to high signal intensity on T2-weighted images.

# Ultrasound
On ultrasound, ganglioneuroma is characterized by a homogeneous, hypoechoic, well circumscribed mass.

# Other Imaging Findings
Other imaging tests for ganglioneuroma include scintigraphy or medaiodobenzylguanidine (MIBG) scan.

# Other Diagnostic Studies
Other diagnostic studies for ganglioneuroma include biopsy, which demonstrates spindle-shaped cells with cell borders in a fibrillar matrix containing ganglion cells with large round nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm.

# Medical Therapy
The predominant therapy for symptomatic ganglioneuroma is surgical resection. Adjunctive chemotherapy and radiotherapy may be required.

# Surgery
Surgery is the mainstay of treatment for symptomatic ganglioneuroma.