Juvenile Nasopharyngeal Angiofibroma Treatment & Management

Hormonal therapy

The testosterone receptor blocker flutamide was reported to reduce stage I and II tumors to 44%. Despite tumor reduction with hormones, this approach is not routinely used. Schuon et al reported on the immunohistochemical analysis of growth mechanisms in juvenile nasopharyngeal angiofibroma.^[2] They concluded that juvenile angiofibroma (JNA) growth and vascularization are driven by factors released from stromal fibroblasts. Therefore, inhibition of these factors might be beneficial for the therapy of inoperable juvenile nasopharyngeal angiofibroma (JNA).

Radiotherapy

Some centers have reported 80% cure rates with radiation therapy. However, concerns regarding potential effects of radiation make radiation therapy a nonuseful modality in most cases.

Stereotactic radiotherapy (ie, Gamma Knife) delivers a lower dose of radiation to surrounding tissues. However, most authorities reserve radiotherapy for intracranial disease or recurrent cases.

Conformal radiotherapy in extensive juvenile nasopharyngeal angiofibroma (JNA) or intracranial extension provides a good alternative to conventional radiotherapy regarding disease control and radiation morbidity, even with advanced disease.^{[3, 4]}

A lateral rhinotomy, transpalatal, transmaxillary, or sphenoethmoidal route is used for small tumors (Fisch stage I or II).

The infratemporal fossa approach is used when the tumor has a large lateral extension.

The midfacial degloving approach, with or without a LeFort osteotomy, improves posterior access to the tumor.

The facial translocation approach is combined with Weber-Ferguson incision and coronal extension for a frontotemporal craniotomy with midface osteotomies for access.

An extended anterior subcranial approach facilitates en bloc tumor removal, optic nerve decompression, and exposure of the cavernous sinus.

Some authors advocate the use of intranasal endoscopic surgery for lesions with limited extension to the infratemporal fossa. Image-guided, endoscopic, laser-assisted removal has also recently been used. Hackman et al (2009) reviewed 31 cases of JNA at the University of Pittsburgh Medical Center from 1995 to 2006^[5] . Most tumors were completely excised using the expanded endonasal approach (EEA) alone or in combination with minor sublabial incisions, avoiding the morbidity associated with larger open approaches or postoperative radiation therapy.

Radical removal of a large JNA may be difficult because of its extreme vascularity and extension to the cavernous sinus, orbit, middle fossa, and anterior fossa. Nevertheless, most of JNAs with intracranial extension can be resected in the first operation with minimal morbidity through a facial degloving and further combination of expanded endoscopic endonasal approaches.^[6]

Preoperative embolization has typically been performed via a transarterial route using a variety of embolic materials. It is accomplished using reabsorbable microparticulate substances (eg, Gelfoam, polyvinyl alcohol, dextran microspheres) or nonabsorbable microparticulates (eg, Ivalon, Terbal). Limiting blood loss during surgery is essential. Endoscopic assistance has been used for direct transnasal tumor puncture and intratumoral embolization using the liquid embolic agent Onyx.^[7]

Preoperative angiography and embolization minimize intraoperative blood loss, and the current shift in the treatment to endoscopic excision in selected cases reduces perioperative morbidity.^[8] Low-grade consumption coagulopathy may complicate small juvenile nasopharyngeal angiofibroma (JNA) and implies that preoperative coagulation screening may have a role in perioperative hemostasis.

Malignant transformation has been reported in 6 cases; 5 of these patients were treated with radiotherapy, according to a study by Makek et al.^[9]

Transient blindness has been reported as a result of embolization, but it is a rare occurrence. Osteoradionecrosis and/or blindness due to optic nerve damage may occur with radiotherapy.

Fistula of the palate at the junction of the soft and hard palate may occur with the transpalatal approach but is prevented by preservation of the greater palatine vessels during flap elevation.

Anesthesia of the cheek is a frequent occurrence with the Weber-Ferguson incision.

The presence of tumor in the pterygoid fossa and basisphenoid, erosion of the clivus, intracranial extension, feeders from the internal carotid artery, a young age, and a residual tumour were risk factors associated with the recurrence of juvenile nasopharyngeal angiofibroma.