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{{CMG}} {{AE}} {{MV}}
{{CMG}} {{AE}} {{MV}}
   
   
{{SK}} Juvenile nasopharyngeal angiofibroma; angiofibroma of the nasopharynx;  
{{SK}} Juvenile nasopharyngeal angiofibroma; angiofibroma of the nasopharynx; JNA
   
   
==Overview==
==Overview==


'''Nasopharyngeal angiofibroma''' (also called juvenile nasopharyngeal angiofibroma) is a histologically [[benign]] but locally aggressive vascular tumor that grows in the back of the nasal cavity. It almost exclusively affects adolescent males. Patients with nasopharyngeal angiofibroma usually present with one-sided nasal obstruction and recurrent bleeding.
'''Nasopharyngeal angiofibroma''' (also called juvenile nasopharyngeal angiofibroma) is a histologically [[benign]] but locally aggressive vascular tumor that grows in the back of the nasal cavity. It almost exclusively affects adolescent males. Patients with nasopharyngeal angiofibroma usually present with one-sided nasal obstruction and recurrent bleeding. Nasopharyngeal angiofibroma may be classified according to Radkowski Classification System into 3 categories: I, II, and III.  Nasopharyngeal angiofibroma is a vascular neoplasm, originates from the pterygopalatine fossa.  The majority of nasopharyngeal angiofibromas are irrigated by the external carotid artery.  Nasopharyngeal angiofibroma is rare, it account for 0.05% of all head and neck tumors. Nasopharyngeal angiofibromas are more commonly observed among  children and adolescents. Common risk factors in the development of nasopharyngeal angiofibroma, include:
presence of tumor in the pterygoid fossa and young age. Early clinical features include epistaxis, facial pain, and headache. The most common symptom is unilateral nasal obstruction.  


==Historical Perspective==
==Historical Perspective==
*Nasopharyngeal angiofibroma was first discovered by [scientist name], a [nationality + occupation], in [year] during/following [event].
*Nasopharyngeal angiofibroma was first described by Hippocrates, a Greek physician, in the 5th century BC.


==Classification==
==Classification==
Line 25: Line 26:


==Pathophysiology==
==Pathophysiology==
*The pathogenesis of nasopharyngeal angiofibroma is characterized by the following features:  
*The pathogenesis of nasopharyngeal angiofibroma is characterized by the following features:<ref name="pmid11374252">{{cite journal |vauthors=Paris J, Guelfucci B, Moulin G, Zanaret M, Triglia JM |title=Diagnosis and treatment of juvenile nasopharyngeal angiofibroma |journal=Eur Arch Otorhinolaryngol |volume=258 |issue=3 |pages=120–4 |year=2001 |pmid=11374252 |doi= |url=}}</ref>
:*Vascular neoplasm  
:*Vascular neoplasm  
:*Originates from the pterygopalatine fossa  
:*Originates from the pterygopalatine fossa  
:*The majority are associated with the external carotid artery
*Genetic alterations  associated with the development of nasopharyngeal angiofibroma, include:<ref name="pmid18228521">{{cite journal |vauthors=Coutinho-Camillo CM, Brentani MM, Nagai MA |title=Genetic alterations in juvenile nasopharyngeal angiofibromas |journal=Head Neck |volume=30 |issue=3 |pages=390–400 |year=2008 |pmid=18228521 |doi=10.1002/hed.20775 |url=}}</ref>
*Genetic alterations  associated with the development of nasopharyngeal angiofibroma, include:<ref name="pmid18228521">{{cite journal |vauthors=Coutinho-Camillo CM, Brentani MM, Nagai MA |title=Genetic alterations in juvenile nasopharyngeal angiofibromas |journal=Head Neck |volume=30 |issue=3 |pages=390–400 |year=2008 |pmid=18228521 |doi=10.1002/hed.20775 |url=}}</ref>
:*Overexpression PDGF-B  
:*Overexpression PDGF-B  
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==Differentiating Nasopharyngeal Angiofibroma from Other Diseases==
==Differentiating Nasopharyngeal Angiofibroma from Other Diseases==
*Nasopharyngeal angiofibroma must be differentiated from other diseases that cause [clinical feature 1], [clinical feature 2], and [clinical feature 3], such as:
*Nasopharyngeal angiofibroma must be differentiated from other diseases that cause epistaxis, unilateral nasal obstruction, and rhinorrhea, such as:
:* Antro-choanal polyp (antral-choanal polyp)
:* Antro-choanal polyp (antral-choanal polyp)
:* Rhinosporidiosis  
:* Rhinosporidiosis  
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:* Nasopharanageal cyst
:* Nasopharanageal cyst
:* Pyogenic granuloma
:* Pyogenic granuloma
 
==Epidemiology and Demographics==
==Epidemiology and Demographics==
:* Nasopharyngeal angiofibroma is rare
* Nasopharyngeal angiofibroma is rare
:* Nasopharyngeal angiofibroma accounts for 0.05% of all head and neck tumors.
* Nasopharyngeal angiofibroma accounts for 0.05% of all head and neck tumors.
:* The prevalence of nasopharyngeal angiofibroma is approximately 1 per 100,000 individuals worldwide.
* The prevalence of nasopharyngeal angiofibroma is approximately 1 per 100,000 individuals worldwide.


===Age===
===Age===
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===Gender===
===Gender===
*Males are more commonly affected with nasopharyngeal angiofibroma than females.
*Males are more commonly affected with nasopharyngeal angiofibroma than females.
*The male to female ratio for nasopharyngeal angiofibroma is approximately 4 to 1.
*The male to female ratio for nasopharyngeal angiofibroma is approximately 4 to 1.
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===Race===
===Race===
*There is no racial predilection for nasopharyngeal angiofibroma.
*There is no racial predilection for nasopharyngeal angiofibroma.
 
*Nasopharyngeal angiofibroma usually affects individuals of the [race 1] race.
*[Race 2] individuals are less likely to develop nasopharyngeal angiofibroma.
==Risk Factors==
==Risk Factors==
*Common risk factors in the development of nasopharyngeal angiofibroma are [risk factor 1], [risk factor 2], [risk factor 3], and [risk factor 4].
*Common risk factors in the development of nasopharyngeal angiofibroma, include:<ref name="pmid11374252">{{cite journal |vauthors=Paris J, Guelfucci B, Moulin G, Zanaret M, Triglia JM |title=Diagnosis and treatment of juvenile nasopharyngeal angiofibroma |journal=Eur Arch Otorhinolaryngol |volume=258 |issue=3 |pages=120–4 |year=2001 |pmid=11374252 |doi= |url=}}</ref>
:*Presence of tumor in the pterygoid fossa
:*Young age
:*Feeders from the internal carotid artery
:*Residual tumor
 
== Natural History, Complications and Prognosis==
== Natural History, Complications and Prognosis==
*The majority of patients with nasopharyngeal angiofibroma are symptomatic at diagnosis.  
*The majority of patients with nasopharyngeal angiofibroma are symptomatic at diagnosis.  
*Early clinical features include epistaxis, facial pain, and headache.
*Early clinical features include epistaxis, facial pain, and headache.
*If left untreated, the majority of patients with nasopharyngeal angiofibroma may progress to develop
*If left untreated, the majority of patients with nasopharyngeal angiofibroma may progress to develop malignant transformation.
*Common complications of nasopharyngeal angiofibroma include transient blindness, optic nerve damage, and low-grade consumption coagulopathy.
*Prognosis is generally good, and the 5-year survival rate of patients with early stage nasopharyngeal angiofibroma is approximately 90%
*Survival rate of patients with late stage nasopharyngeal angiofibroma is approximately 40%


*The most common complication of nasopharyngeal angiofibroma is
*Prognosis is generally [excellent/good/poor], and the [1/5/10­year mortality/survival rate] of patients with nasopharyngeal angiofibroma is approximately [#%].
== Diagnosis ==
== Diagnosis ==
===Diagnostic Criteria===
===Diagnostic Criteria===
*The diagnosis of nasopharyngeal angiofibroma is made when at least [number] of the following [number] diagnostic criteria are met:
*The diagnosis of nasopharyngeal angiofibroma is with the following diagnostic criteria:<ref name="pmid11374252">{{cite journal |vauthors=Paris J, Guelfucci B, Moulin G, Zanaret M, Triglia JM |title=Diagnosis and treatment of juvenile nasopharyngeal angiofibroma |journal=Eur Arch Otorhinolaryngol |volume=258 |issue=3 |pages=120–4 |year=2001 |pmid=11374252 |doi= |url=}}</ref>
:*[criterion 1]
:*Clinical criteria
:*[criterion 2]
::*Young patient
:*[criterion 3]
::*Epistaxis
:*[criterion 4]
:*Positive physical exam
::*A smooth submucosal mass in the posterior nasal cavity
:*Positive imaging finding: visualisation of a nasopharyngeal mass
 
=== Symptoms ===
=== Symptoms ===
*Common symptoms of nasopharyngeal angiofibroma, may include:
*Common symptoms of nasopharyngeal angiofibroma, may include:<ref name="pmid11374252">{{cite journal |vauthors=Paris J, Guelfucci B, Moulin G, Zanaret M, Triglia JM |title=Diagnosis and treatment of juvenile nasopharyngeal angiofibroma |journal=Eur Arch Otorhinolaryngol |volume=258 |issue=3 |pages=120–4 |year=2001 |pmid=11374252 |doi= |url=}}</ref>
:*Epistaxis or blood-tinged nasal discharge
:*Epistaxis or blood-tinged nasal discharge
:*Unilateral nasal obstruction  
:*Unilateral nasal obstruction  
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=== Laboratory Findings ===
=== Laboratory Findings ===
*Laboratory findings consistent with the diagnosis of nasopharyngeal angiofibroma, include:
*There are no specific laboratory findings associated with the diagnosis of nasopharyngeal angiofibroma.
 
 
 
   
   
===Imaging Findings===
===Imaging Findings===
*Computed tomography is the imaging modality of choice for nasopharyngeal angiofibroma.
*Computed tomography is the imaging modality of choice for nasopharyngeal angiofibroma.<ref name="pmid11374252">{{cite journal |vauthors=Paris J, Guelfucci B, Moulin G, Zanaret M, Triglia JM |title=Diagnosis and treatment of juvenile nasopharyngeal angiofibroma |journal=Eur Arch Otorhinolaryngol |volume=258 |issue=3 |pages=120–4 |year=2001 |pmid=11374252 |doi= |url=}}</ref>
*On conventional radiography, findings of nasopharyngeal angiofibroma, include:  
*On conventional radiography, findings of nasopharyngeal angiofibroma, include:  
:*Visualisation of a nasopharyngeal mass
:*Visualisation of a nasopharyngeal mass
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=== Other Diagnostic Studies ===
=== Other Diagnostic Studies ===
*Nasopharyngeal angiofibroma may also be diagnosed using [diagnostic study name].
*Nasopharyngeal angiofibroma may also be diagnosed using nasal [[endoscopy]].  
*Findings on [diagnostic study name] include [finding 1], [finding 2], and [finding 3].
   
   
== Treatment ==
== Treatment ==
=== Medical Therapy ===
=== Medical Therapy ===
*There is no treatment for nasopharyngeal angiofibroma; the mainstay of therapy is supportive care.
*Medical therapy for nasopharyngeal angiofibroma is divided into 2 categories:<ref name="pmid11374252">{{cite journal |vauthors=Paris J, Guelfucci B, Moulin G, Zanaret M, Triglia JM |title=Diagnosis and treatment of juvenile nasopharyngeal angiofibroma |journal=Eur Arch Otorhinolaryngol |volume=258 |issue=3 |pages=120–4 |year=2001 |pmid=11374252 |doi= |url=}}</ref>
:*Hormonal therapy
*The mainstay of therapy for nasopharyngeal angiofibroma is [medical therapy 1] and [medical therapy 2].
:*Radiotherapy
*[Medical therapy 1] acts by [mechanism of action1].
*Hormonal therapy for nasopharyngeal angiofibroma, includes:
*Response to [medical therapy 1] can be monitored with [test/physical finding/imaging] every [frequency/duration].
:*Flutamide
*Medical treatment is usually given before surgery to reduce the blood loss
*Radiotherapy for nasopharyngeal angiofibroma, include:
:*Stereotactic radiotherapy
 
=== Surgery ===
=== Surgery ===
*Surgery is the mainstay of therapy for nasopharyngeal angiofibroma.
*Surgery is the mainstay of therapy for nasopharyngeal angiofibroma.
*[Surgical procedure] in conjunction with [chemotherapy/radiation] is the most common approach to the treatment of nasopharyngeal angiofibroma.
*Surgical approach for nasopharyngeal angiofibroma will depend on the stage.
*[Surgical procedure] can only be performed for patients with [disease stage] nasopharyngeal angiofibroma.
:*The treatment of choice  for early stage for nasopharyngeal angiofibroma is intranasal endoscopic surgery. Lateral rhinotomy is the usual preferred surgical approach of choice.  
:*The treatment of choice  for late stage for nasopharyngeal angiofibroma include the infratemporal fossa approach, and the mid-facial degloving approach.  
 
=== Prevention ===
=== Prevention ===
*There are no primary preventive measures available for nasopharyngeal angiofibroma.
*There are no primary preventive measures available for nasopharyngeal angiofibroma.
*Once diagnosed and successfully treated, patients with nasopharyngeal angiofibroma are followed-up after surgery, and every 3, 6, or 12 months.  
*Effective measures for the primary prevention of nasopharyngeal angiofibroma include [measure1], [measure2], and [measure3].
 
*Once diagnosed and successfully treated, patients with nasopharyngeal angiofibroma are followed-up every [duration]. Follow-up testing includes [test 1], [test 2], and [test 3].  


==References==
==References==

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Maria Fernanda Villarreal, M.D. [2]

Synonyms and keywords: Juvenile nasopharyngeal angiofibroma; angiofibroma of the nasopharynx; JNA

Overview

Nasopharyngeal angiofibroma (also called juvenile nasopharyngeal angiofibroma) is a histologically benign but locally aggressive vascular tumor that grows in the back of the nasal cavity. It almost exclusively affects adolescent males. Patients with nasopharyngeal angiofibroma usually present with one-sided nasal obstruction and recurrent bleeding. Nasopharyngeal angiofibroma may be classified according to Radkowski Classification System into 3 categories: I, II, and III. Nasopharyngeal angiofibroma is a vascular neoplasm, originates from the pterygopalatine fossa. The majority of nasopharyngeal angiofibromas are irrigated by the external carotid artery. Nasopharyngeal angiofibroma is rare, it account for 0.05% of all head and neck tumors. Nasopharyngeal angiofibromas are more commonly observed among children and adolescents. Common risk factors in the development of nasopharyngeal angiofibroma, include: presence of tumor in the pterygoid fossa and young age. Early clinical features include epistaxis, facial pain, and headache. The most common symptom is unilateral nasal obstruction.

Historical Perspective

  • Nasopharyngeal angiofibroma was first described by Hippocrates, a Greek physician, in the 5th century BC.

Classification

  • Nasopharyngeal angiofibroma may be classified according to Radkowski Classification System into 3 categories:
  • Stage I
  • Ia: limited to nasal cavity/nasopharynx
  • Ib: extension into one or more paranasal sinuses
  • Stage II
  • IIa: minimal extension through sphenopalatine foramen into pterygomaxillary fossa
  • IIb: fills pterygomaxillary fossa bowing the posterior wall of the maxiallary antrum anteriorly or extending into the orbit via the inferior orbital fissure.
  • IIc: extends beyond pterygomaxillary fossa into infratemporal fossa
  • Stage III
  • Stage IIIA: intracranial extension

Pathophysiology

  • The pathogenesis of nasopharyngeal angiofibroma is characterized by the following features:[1]
  • Vascular neoplasm
  • Originates from the pterygopalatine fossa
  • The majority are associated with the external carotid artery
  • Genetic alterations associated with the development of nasopharyngeal angiofibroma, include:[2]
  • Overexpression PDGF-B
  • Overexpression bFGF
  • Overexpression bFGF
  • Deletion of chromosome 17
  • Tumor suppressor gene p53
  • Overexpression of Her-2/neu oncogene
  • On gross pathology, characteristic findings of nasopharyngeal angiofibroma, include:
  • Unencapsulated
  • Polypoid fibrous mass
  • Bleeding on manipulation
  • On microscopic histopathological analysis, characteristic findings of nasopharyngeal angiofibroma, include:
  • Fibroblastic cells with plump (near cuboidal) nuclei
  • Fibrous stroma
  • Abundant capillaries

Causes

  • There are no known causes of nasopharyngeal angiofibroma.

Differentiating Nasopharyngeal Angiofibroma from Other Diseases

  • Nasopharyngeal angiofibroma must be differentiated from other diseases that cause epistaxis, unilateral nasal obstruction, and rhinorrhea, such as:
  • Antro-choanal polyp (antral-choanal polyp)
  • Rhinosporidiosis
  • Malignancy
  • Chordoma
  • Nasopharanageal cyst
  • Pyogenic granuloma

Epidemiology and Demographics

  • Nasopharyngeal angiofibroma is rare
  • Nasopharyngeal angiofibroma accounts for 0.05% of all head and neck tumors.
  • The prevalence of nasopharyngeal angiofibroma is approximately 1 per 100,000 individuals worldwide.

Age

  • Nasopharyngeal angiofibroma is more commonly observed among patients aged 7-19 years
  • Nasopharyngeal angiofibroma is more commonly observed among children and adolescents .

Gender

  • Males are more commonly affected with nasopharyngeal angiofibroma than females.
  • The male to female ratio for nasopharyngeal angiofibroma is approximately 4 to 1.

Race

  • There is no racial predilection for nasopharyngeal angiofibroma.

Risk Factors

  • Common risk factors in the development of nasopharyngeal angiofibroma, include:[1]
  • Presence of tumor in the pterygoid fossa
  • Young age
  • Feeders from the internal carotid artery
  • Residual tumor

Natural History, Complications and Prognosis

  • The majority of patients with nasopharyngeal angiofibroma are symptomatic at diagnosis.
  • Early clinical features include epistaxis, facial pain, and headache.
  • If left untreated, the majority of patients with nasopharyngeal angiofibroma may progress to develop malignant transformation.
  • Common complications of nasopharyngeal angiofibroma include transient blindness, optic nerve damage, and low-grade consumption coagulopathy.
  • Prognosis is generally good, and the 5-year survival rate of patients with early stage nasopharyngeal angiofibroma is approximately 90%
  • Survival rate of patients with late stage nasopharyngeal angiofibroma is approximately 40%

Diagnosis

Diagnostic Criteria

  • The diagnosis of nasopharyngeal angiofibroma is with the following diagnostic criteria:[1]
  • Clinical criteria
  • Young patient
  • Epistaxis
  • Positive physical exam
  • A smooth submucosal mass in the posterior nasal cavity
  • Positive imaging finding: visualisation of a nasopharyngeal mass

Symptoms

  • Common symptoms of nasopharyngeal angiofibroma, may include:[1]
  • Epistaxis or blood-tinged nasal discharge
  • Unilateral nasal obstruction
  • Rhinorrhea
  • Hearing loss
  • Diplopia
  • Rarely anosmia
  • Eye pain

Physical Examination

  • Patients with nasopharyngeal angiofibroma usually are well-appearing.
  • Physical examination may be remarkable for:
  • A smooth submucosal mass in the posterior nasal cavity

Laboratory Findings

  • There are no specific laboratory findings associated with the diagnosis of nasopharyngeal angiofibroma.

Imaging Findings

  • Computed tomography is the imaging modality of choice for nasopharyngeal angiofibroma.[1]
  • On conventional radiography, findings of nasopharyngeal angiofibroma, include:
  • Visualisation of a nasopharyngeal mass
  • Opacification of the sphenoid sinus
  • Anterior bowing of the posterior wall of the maxillary antrum
  • Holman-miller sign: the anterior bowing of the posterior wall of the maxillary antrum which is seen on lateral skull film or cross-sectional imaging
  • Widening of the pterygomaxillary fissure and pterygopalatine fossa
  • Erosion of the medial pterygoid plate
  • On CT, findings of nasopharyngeal angiofibroma, include:
  • Bony changes
  • Non-encapsulated soft tissue mass
  • Bowing the posterior wall of the maxillary antrum anteriorly
  • On MRI, findings of nasopharyngeal angiofibroma, include:
  • T1: intermediate signal
  • T2: heterogeneous signal: flow voids appear dark
  • T1 C+ (Gd): shows prominent enhancement
  • The images below demonstrate findings of nasopharyngeal angiofibroma.

Other Diagnostic Studies

  • Nasopharyngeal angiofibroma may also be diagnosed using nasal endoscopy.

Treatment

Medical Therapy

  • Medical therapy for nasopharyngeal angiofibroma is divided into 2 categories:[1]
  • Hormonal therapy
  • Radiotherapy
  • Hormonal therapy for nasopharyngeal angiofibroma, includes:
  • Flutamide
  • Medical treatment is usually given before surgery to reduce the blood loss
  • Radiotherapy for nasopharyngeal angiofibroma, include:
  • Stereotactic radiotherapy

Surgery

  • Surgery is the mainstay of therapy for nasopharyngeal angiofibroma.
  • Surgical approach for nasopharyngeal angiofibroma will depend on the stage.
  • The treatment of choice for early stage for nasopharyngeal angiofibroma is intranasal endoscopic surgery. Lateral rhinotomy is the usual preferred surgical approach of choice.
  • The treatment of choice for late stage for nasopharyngeal angiofibroma include the infratemporal fossa approach, and the mid-facial degloving approach.

Prevention

  • There are no primary preventive measures available for nasopharyngeal angiofibroma.
  • Once diagnosed and successfully treated, patients with nasopharyngeal angiofibroma are followed-up after surgery, and every 3, 6, or 12 months.

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Paris J, Guelfucci B, Moulin G, Zanaret M, Triglia JM (2001). "Diagnosis and treatment of juvenile nasopharyngeal angiofibroma". Eur Arch Otorhinolaryngol. 258 (3): 120–4. PMID 11374252.
  2. Coutinho-Camillo CM, Brentani MM, Nagai MA (2008). "Genetic alterations in juvenile nasopharyngeal angiofibromas". Head Neck. 30 (3): 390–400. doi:10.1002/hed.20775. PMID 18228521.