The greatest challenge in the surgical treatment of angiofibromas is dealing with the hypervascularity of these tumors. Staging systems that take into account the vascularity of the tumor may be more prognostic. A variety of treatment strategies are used to deal with the vascularity of angiofibromas, including preoperative embolization, segmentation of the tumor into vascular territories, use of hemostatic tools, and staging of surgery. Even large angiofibromas with intracranial extension and residual vascularity can be successfully managed by a skull base team using endoscopic techniques.
Key learning points
At the end of this article, the reader will:
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Know which techniques can be used to devascularize a sinonasal tumor.
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Know the major source of morbidity when removing vascular tumors such as angiofibromas.
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Be able to describe a staging system for angiofibromas that incorporates residual vascularity of the tumor as a prognostic factor.
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Know the most common source of blood supply from the internal carotid artery for an angiofibroma.
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Know the key anatomic landmarks for locating the petrous segment of the internal carotid artery.
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Know which blood-sparing strategies can be used to minimize the need for blood transfusion.
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Introduction
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Rare, benign, vascular tumor
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Male adolescents
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Origin: nasopharynx in region of pterygoid canal
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Symptoms: nasal obstruction, recurrent unilateral epistaxis
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Facial swelling
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Orbit: proptosis, diplopia, visual loss
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Facial hypesthesia (V2)
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Primary treatment is surgery
Juvenile nasopharyngeal angiofibroma (JNA) is a rare, benign tumor that is characteristically found in male adolescents. It arises in the lateral nasopharynx and can spread in multiple directions: nasal cavity, oropharynx, paranasal sinuses, orbit (via inferior orbital fissure), and infratemporal fossa (via pterygomaxillary fissure). Intracranial extension occurs through skull base foramina and erosion of bone. Early symptoms include nasal obstruction and recurrent unilateral epistaxis. Large tumors can displace normal structures, resulting in facial swelling, proptosis, diplopia, visual loss, and facial hypesthesia. The primary treatment is surgical excision. The greatest challenge of surgery is bleeding caused by the hypervascular nature of JNA.
Introduction
- •
Rare, benign, vascular tumor
- •
Male adolescents
- •
Origin: nasopharynx in region of pterygoid canal
- •
Symptoms: nasal obstruction, recurrent unilateral epistaxis
- ○
Facial swelling
- ○
Orbit: proptosis, diplopia, visual loss
- ○
Facial hypesthesia (V2)
- ○
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Primary treatment is surgery
Juvenile nasopharyngeal angiofibroma (JNA) is a rare, benign tumor that is characteristically found in male adolescents. It arises in the lateral nasopharynx and can spread in multiple directions: nasal cavity, oropharynx, paranasal sinuses, orbit (via inferior orbital fissure), and infratemporal fossa (via pterygomaxillary fissure). Intracranial extension occurs through skull base foramina and erosion of bone. Early symptoms include nasal obstruction and recurrent unilateral epistaxis. Large tumors can displace normal structures, resulting in facial swelling, proptosis, diplopia, visual loss, and facial hypesthesia. The primary treatment is surgical excision. The greatest challenge of surgery is bleeding caused by the hypervascular nature of JNA.
Why is bleeding a problem?
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Increased risk of injury caused by poor visualization
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Incomplete surgery caused by poor visualization or volume of blood loss
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Medical morbidity:
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Postoperative nausea and fatigue
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Hypoxia (from blood loss and nasal packing)
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Transfusion of blood products
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Increased medical cost
Surgical bleeding is to be expected with the management of large and vascular tumors such as JNA. Other tumors that are characterized by increased vascularity are meningioma, sinonasal malignancy, hemangiopericytoma, and metastatic renal cell carcinoma. Bleeding with poor visualization is a primary risk factor for complications such as cranial nerve injury, cerebrospinal fluid leak, and vascular injury. Poor visualization and excessive blood loss also limit the ability to completely remove the tumor; staging of surgery may be necessary. Additional morbidities include postoperative nausea from swallowed blood, postoperative anemia, and the risks of blood transfusion. Deaths still occur from unmanaged blood loss. Excessive blood loss increases the costs of health care because of greater use of resources, treatment of complications, and prolonged hospitalization.
Small JNAs receive their blood supply from the external carotid artery (ECA) and can be effectively devascularized by preoperative embolization or surgical ligation of the internal maxillary artery. Intraoperative endoscopic ligation of the ethmoid and sphenopalatine arteries can often be performed by working around the periphery of the tumor or through an external approach.
Larger JNAs receive a blood supply from multiple sources, including the internal carotid artery (ICA). For such tumors, the best treatment strategy is controversial and depends on the capabilities and resources of the surgical team. With proper planning, even giant JNAs can be effectively managed using minimally invasive surgical approaches.
Goals of treatment
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Complete removal of tumor
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Access to routes of extension
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Vascular control
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Minimize morbidity
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Blood loss and transfusion
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Cranial nerve injury
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Disruption of growth centers/cosmesis
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Brain manipulation
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Soft tissue injury/pain
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Avoid radiation therapy
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Long-term side effects
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In addition to complete removal, the goals of treatment are to minimize morbidity and avoid the use of radiation therapy. Intraoperative bleeding is the major source of morbidity and contributes to incomplete tumor resection and complications caused by poor visualization. Concerns about bleeding or incomplete surgery may result in inappropriate use of radiation therapy.
Staging of angiofibromas
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Age, weight
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Prior treatment
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Tumor size, volume
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Sites of tumor involvement
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Skull base involvement
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Intracranial extension
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ICA contribution
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Residual vascularity
Potential prognostic factors for the treatment of JNAs include the size, location, and extent of the tumor. Multiple staging systems have been proposed over the years for prognostic classification of JNA ( Table 1 ). Key staging criteria include the tumor extent and presence of skull base involvement and intracranial extension. The greatest challenge of these surgeries is not the size or extent of the tumor but intraoperative hemorrhage that cannot be controlled by embolization or ligation of branches of the ECA. In particular, these staging systems do not account for the vascularity of the tumor (following embolization) and the route of intracranial extension (medial or lateral to ICA and cavernous sinus).
| Stage | Onerci et al, 2006 | Radkowski et al, 1996 | Andrews et al, 1989 | Chandler et al, 1984 | Sessions et al, 1981 |
|---|---|---|---|---|---|
| I | Nose, NP, ethmoid and sphenoid sinuses, or minimal extension into PMF |
| Limited to NP Bone destruction negligible or limited to SPF | Limited to NP |
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| II | Maxillary sinus, full occupation of PMF, extension to anterior cranial fossa, limited extension into ITF |
| Invading PPF or maxillary, ethmoid, or sphenoid sinus with bone destruction | Extension into nasal cavity or sphenoid sinus |
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| III | Deep extension into cancellous bone at pterygoid base or body and GW sphenoid; significant lateral extension into ITF or pterygoid plates; orbital, cavernous sinus obliteration |
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| Tumor into antrum, ethmoid sinus, PMF, ITF, orbit, and/or cheek | Intracranial extension |
| IV | Intracranial extension between pituitary gland and ICA, tumor localization lateral to ICA, middle fossa extension, and extensive intracranial extension | — |
| Intracranial extension | — |
The University of Pittsburgh Medical Center (UPMC) staging system ( Table 2 ), proposed in 2010, separates JNA tumors into 3 groups based on the vascularity and extent of the tumor. Tumors in stages I and II receive their entire blood supply from branches of the ECA and are readily excised (following embolization) using endoscopic techniques with little morbidity. Stage III tumors are intermediate risk and are characterized by skull base erosion or lateral extension but without residual vascularity. Stage IV and V tumors are challenging to treat because of significant blood supply from the ICA. Routes of intracranial extension may be from the sphenoid sinus medial to the cavernous sinus or lateral to the ICA through the orbital fissures to the middle cranial fossa ( Fig. 1 ).
