Diagnosis: Juvenile nasopharyngeal angiofibroma (JNA), Radkowski grade Ib
The MRIs (Figure 2and Figure 3) revealed a heterogeneous solid and cystic mass expanding the left nasal cavity, with the cystic components of the mass containing fluid-fluid levels suggestive of hemorrhage. Images obtained after gadolinium administration demonstrated robust mass enhancement. The mass appeared to originate from the left sphenopalatine foramen, without significant pterygopalatine fossa or skull base extension. The tumor did not involve the cavernous sinus (data not shown). The computed tomographic findings complemented the MRI results by demonstrating mass erosion of the left inferior sphenoid wall and some associated remodeling of the left sphenoethmoidal recess (Figure 4).
The combination of the patient's age and sex, together with the imaging findings of a prominently contrast-enhancing mass originating near the sphenopalatine foramen, suggested the likely diagnosis of JNA. However, the absence of extensive pterygopalatine fossa involvement and the presence of large cystic cavitations are atypical JNA features. Alternative diagnoses considered were rhabdomyosarcoma, lymphoma, esthesioneuroblastoma, and schwannoma. The heterogeneity of the mass on MRIs and the lack of extensive bony destruction made the diagnosis of rhabdomyosarcoma less likely, whereas the cavitary appearance of the lesion argued against lymphoma, which characteristically has a solid homogeneous appearance. Esthesioneuroblastoma was considered unlikely given the lesion's typical upper nasal cavity origin adjacent to the cribriform plate; furthermore, neurogenic neoplasms such as schwannoma can present as an expansile nasal cavity mass that avidly enhances on MRIs, but the fluid-fluid levels observed in this case would be highly unusual for a schwannoma.1
Surgical resection was planned for definitive diagnostic and therapeutic purposes. Both an endoscopic approach and an open lateral rhinotomy approach were considered. Given the possibility of a JNA and the bleeding risks thereof, angiography was performed before surgery. Angiography revealed extensive tumor blush arising principally from the right and left sphenopalatine arteries and persisting into the venous phase, findings strongly suggestive of JNA.2Selective embolization of both sphenopalatine arteries eradicated more than 90% of the lesion's vascularity; some lateral vascular elements remained patent via the left superior alveolar artery. An operative endoscopic resection of the mass was subsequently performed within 36 hours of the angiographic procedure. The lesion was excised from the left nasal cavity, nasopharynx, and sphenoid sinus, with particular attention focused at its suspected origin in the region of the sphenopalatine foramen. The findings of intraoperative frozen-section assessment and subsequent histopathologic examination confirmed the diagnosis of JNA.
This case illustrates several important aspects in the diagnosis and treatment of JNA. Accurate staging of JNA is critical for surgical planning. There are several grading schemes based on radiographic findings; 2 of the more commonly used are the modified Fisch and Radkowski classification systems. The modified Fisch classification describes stage I tumors as limited to the nasopharynx and nasal cavity; stage II tumors as invading the pterygopalatine fossa or the sinuses with bone destruction; stage III tumors as invading the infratemporal fossa or orbit with or without intracranial extradural involvement; and stage IV tumors as intradural tumors with or without infiltration of the cavernous sinus, pituitary fossa, or optic chiasm. The Radkowski classification divides stage I tumors into those limited to the nasal cavity and nasopharynx (Ia) and those with solely paranasal sinus extension (Ib). Stage II tumors are separated into those exhibiting minimal extension to the pterygomaxillary fossa (IIa), those fully occupying the pterygomaxillary fossa with or without orbital bone erosion (IIb), and those extending to the infratemporal fossa or posterior to the pterygoid plates (IIIc). Radkowski stage III tumors are large masses that erode the skull base with minimal (IIIa) or extensive (IIIb) intracranial or cavernous sinus involvement.3Given the primary location of our patient's JNA within the nasal cavity and nasopharynx, with sphenoid sinus invasion but no pterygomaxillary fossa extension, this tumor's final classification was Radkowski stage Ib.
The treatment of JNA is in evolution. Historically, the lateral rhinotomy and midfacial degloving procedures have been the preferred open surgical approaches for JNA resection owing to the excellent exposure afforded by these methods, with the infratemporal approach reserved for very large tumors with substantial lateral extension.3- 5Endoscopic resection, as used in this case, has become an increasingly favored method of resection for grades I and II JNA, and endoscopic resection or assistance is becoming more frequently used in the surgical treatment of even advanced-grade JNA.6Open procedures remain necessary in the treatment of JNA with substantial intracranial extension and when the JNA extends posterior to the pterygoid plates or lateral to the cavernous sinus.3Regardless of stage or the method chosen for surgical excision, preoperative angiography and embolization are strongly recommended given the vascularity of the lesion and the risk of significant operative bleeding.2
Radiotherapy may be considered for nonresectable high-grade tumors with substantial intracranial or intraorbital extension. Two recent relatively large published series reported local and regional control rates of approximately 85% for this mode of treatment.7,8The risks of cranial irradiation reported in these series are significant—growth retardation, temporal lobe necrosis, and cataracts—but may be lessened in the future by intensity-modulated radiotherapy and proton beam techniques.3
Recurrence of JNA is thought to typically result from residual disease. The skull base, particularly the basisphenoid, is a common suspected site, and drilling of the sphenoid base is recommended to decrease the incidence of recidivism.9Although detailed protocols regarding the timing of follow-up examinations and imaging are lacking, close monitoring is suggested, with periodic endoscopic office examinations and initial postoperative imaging within 3 to 6 months of treatment.10The results of such postoperative imaging must be interpreted carefully because soft-tissue abnormalities secondary to scarring can masquerade as residual or recurrent disease.8
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Radiology Quiz Case 2: Diagnosis. Arch Otolaryngol Head Neck Surg. 2010;136(7):742-743. doi:10.1001/archoto.2010.97-b