Angiofibroma

SkinTumors-P6030158[1]

Angiofibroma is benign, but highly aggressive vascular tumor of the nasopharynx that is almost exclusively seen in male adolescents. The posterolateral wall of the nasal cavity is the most common site of origin. Nasal obstruction and epistaxis are reported in the vast majority of patients. CT scan, MRI or nasal endoscopy can confirm the diagnosis, while surgery is the main form of treatment.

Presentation

Clinical presentation of patients suffering from angiofibroma almost always consists of unilateral nasal obstruction and epistaxis [4]. Epistaxis may sometimes be quite severe and/or recurrent. A plethora of other symptoms may be present, including a headache, facial pain, facial swelling, rhinorrhea, hyposmia, ipsilateral hearing loss and diplopia. In rare cases, cranial nerve palsy may be seen [8]. Studies have established that symptoms last between 6-12 months before a diagnosis is made, which implies that this condition should be thought of more often, especially if such symptoms are exhibited in adolescent boys [4].

Workup

A presumptive diagnosis can be made after a thorough patient history regarding the onset and duration of symptoms, and a full physical examination, including inspection of the oral cavity and anterior rhinoscopy. To confirm the presence of angiofibroma, various imaging studies may be conducted. Although plain radiographs of the sinuses may show a mass, CT or MRI are favored diagnostic methods, as they can show the exact anatomical location of the tumor [9]. Nasal endoscopy may also prove as an efficient method as it provides a direct view into the nasopharynx. Endoscopy can reveal either a pink or wine-colored mass, while a pale-to-white color is also reported, with the color depending on the amount of vascular involvement [1]. Angiography is a highly useful imaging technique, which enables full visualization of all arteries branching from the internal carotid vessel and provides an optimal view for the surgeon to determine the best approach in therapy. In some instances, a biopsy may be performed, and histopathological examination reveals connective tissue made of fibroblasts surrounded by a rich capillary bed. Because the tumor may significantly bleed, however, this procedure is rarely indicated.

Treatment

Recent advances in surgery have placed the endoscopic endonasal approach at the top of the list when it comes to choosing optimal treatment approaches [10] [11]. Endoscopy is shown to reduce blood loss and the duration of hospital stay, but more importantly, minimize the rates of recurrence compared to open surgery [12]. Preoperative embolization of blood vessels that supply the tumor has shown significant benefit in terms of the amount of blood loss and reduction in the overall difficulty of surgical management of patients with this tumor [13]. In stages, I, II and III, surgical management is sufficient for complete eradication of the tumor, but patients in whom a stage IV angiofibroma is confirmed, adjuvant radiation or chemotherapy may be indicated [14].

Prognosis

The prognosis of the tumor depends on the stage of the diagnosis, but overall rates of recovery are very good with efficient surgery. Recurrence may occur, however, and usually, results from incomplete resection of the tumor.

Etiology

The exact cause of angiofibroma is not known, but several studies have shown its association with familial adenomatous polyposis (FAP) [6]. Mutations in β-catenin genes have shown to be present in a substantial number of patients [7]. More importantly, these mutations have been established in fibroblasts, rather than endothelial cells, which indicates that the neoplastic cells are actually stromal cells [7]. Because this tumor develops exclusively in male adolescents and because numerous steroid receptors have been found, it is suspected that male sex hormones are important factors in the pathogenesis of this disease [7].

Epidemiology

This benign tumor comprises between 0.05-0.5% of all tumors of the head and neck and is estimated to develop in approximately 1 in 150,000 individuals, making it an extremely rare finding in medical practice [2]. It is almost exclusively seen in males during the adolescent period and the majority of patients are between 14-25 years [2]. Ethnic predilection is not established. Some studies have reported a significantly increased incidence rate of this tumor in patients with FAP, presumably due to shared genetic mutations. [6].

Sex distribution
Age distribution

Pathophysiology

Although the exact cause remains unknown, patterns of growth and consequent appearance of symptoms depending on its proliferation have been determined [1] [2]. Once it develops somewhere on the posterolateral wall of the nasopharynx, usually near the sphenopalatine foramen, it can grow anteriorly, superiorly or laterally. In the case of anterior growth, the tumor may protrude the nasal fossa and eventually reach the middle turbinate, damaging numerous vessels and bleeding from its own rich vasculature, thus causing epistaxis, rhinorrhea, and unilateral nasal obstruction. In the case of lateral growth, the maxillary sinus may be involved, while severe proliferation may lead to invasion of the tumor into the infratemporal fossa, resulting in disturbances of the auditory apparatus. Destruction of the sphenoidal sinus, the involvement of orbital fissures and the dura may result from anterior growth of the tumor, leading to symptoms such as diplopia, ptosis, and ocular disturbances.

Because the tumor may involve various tissues and anatomical structures, several classification systems have been used in the staging of this formation. The Fisch method is one of the most commonly used and divides the tumor into following stages [2]:

  • Stage I - The tumor is restricted to the nasopharynx and the sphenopalatine foramen, without the involvement of adjacent bony structures.
  • Stage II - Invasion of adjacent nasal sinuses or the pterygomaxillary fossa accompanied with bone destruction.
  • Stage III - The infratemporal fossa or the orbit are invaded by the tumor, either with intracranial involvement (IIIb) or without (IIIa).
  • Stage IV - The intracranial spread of the tumor, together with the involvement of the optic chiasm, sella turcica or the cavernous sinus (IVb) or without the involvement (IVa).

Prevention

As exact pathogenic mechanisms that lead to the development of this tumor, prevention strategies currently do not exist.

Summary

Angiofibroma is a rare, benign vascular tumor that originates in the posterolateral wall of the nasopharynx, with an estimated incidence of 1 in 150,000 individuals [1]. This tumor comprises less than 0.5% of all head and neck tumors and for unknown reasons, it is almost exclusively seen in adolescent males between 14-25 years; it is frequently mentioned in literature as juvenile nasopharyngeal angiofibroma [2]. Although benign in its nature, it is highly aggressive and may cause significant destruction of adjacent tissues. From the nasopharynx and the superior border of the sphenopalatine foramen, which is thought to be its initial location, the tumor may extend to the nasal septum, involve sphenoid and maxillary sinus and the infratemporal fossa [1]. Very rare cases have described extra-nasopharyngeal locations [3]. As a result, this tumor may give various symptoms depending on the sites that are damaged. The clinical presentation includes epistaxis (often severe) and unilateral nasal obstruction, while a headache, hearing impairment, rhinorrhea, facial swelling, ptosis, and hyposmia is also reported [4]. Symptoms are often recurrent and progressive in nature and are important distinguishing characteristics from other conditions that may manifest with similar complaints. To make the diagnosis, imaging studies such as computed tomography (CT), magnetic resonance imaging (MRI) or nasal endoscopy may be performed. All of these methods can identify a mass in the nasopharynx as well as extension into different tissues. The histological examination will reveal dense fibrous tissue and numerous blood vessels, as this tumor is of vascular origin, but it is important to note that biopsy is not always indicated. This type of tumor is suspected to include the risk of severe bleeding [1]. One of the reasons why this tumor is prone to severe bleeding is because its rich vascular bed stems from the maxillary artery (in the majority of cases, the sphenopalatine artery, its terminal branch), which arises from the internal carotid artery. Treatment principles invariably include a surgical approach guided by imaging studies that aid in determining the stage of the tumor [5]. There are various classification methods, the most prominent being the Fisch method, which stages angiofibroma from I (the tumor is located in the sphenopalatine foramen without invasion of other structures) to IV (invasion of extradural and/or intradural structures) [2]. Surgical treatment mandates preoperative embolization of vessels that supply the tumor, followed by endoscopic resection, as this minimally invasive technique has shown reduced hospital stay, less postoperative pain and reduced rates of recurrence. Overall, this tumor has a very good prognosis without sequelae after appropriate surgical therapy. Moreover, an early diagnosis may prevent its growth and infiltration into the surrounding structures that may result in more significant damage. However, recurrence of this tumor has shown to occur in a significant number of patients.

Patient Information

Angiofibroma is a rare benign, but a very aggressive tumor that originates in the nasopharynx, the anatomical part which connects the nasal and the oral cavity. It is estimated to develop in approximately 1 in 150,000 individuals and for some reason, it is almost exclusively seen in boys (which is why it is also known as juvenile nasopharyngeal angiofibroma), presumably because male sex hormones are involved in the pathogenesis. This tumor may invade various tissues around it and give numerous symptoms, but in the majority of cases, recurrent and often severe nose bleeding, as well as unilateral nasal obstruction, are reported. Headaches, rhinorrhea, hearing and vision disturbances, as well as facial swelling and pain, may be reported by patients. To make the diagnosis, a detailed physical examination and the use of imaging studies will reveal a mass that can be classified into four stages, I being the presence of a tumor without invasion into adjacent tissues and IV implying diffuse infiltration. Computed tomography (CT scan), magnetic resonance imaging (MRI) and nasal endoscopy can all be used to identify the exact location of the tumor. Because this growth is highly vascular, an imaging technique called angiography is often performed, which visualizes all blood vessels arising from the neck. This procedure provides important data that are used to determine the optimal approach to treatment, which is surgery. Surgery comprises total excision of the tumor, when possible, while patients in whom the diagnosis of stage IV angiofibroma may require adjuvant chemotherapy or radiation. An endoscopic approach is preferred over open surgery because of significantly less cosmetic sequelae, shorter duration of hospital stay, but most importantly, lower rates of recurrence have been observed with this surgical method. Prior to removal of the tumor, the blood supply to the tumor is abolished by performing embolization, to reduce bleeding during the operation. This tumor has a good prognosis, but the diagnosis is often delayed because of insufficient clinical suspicion by the physicians. For these reasons, male adolescents who report recurrent symptoms such as nose bleeding and nasal obstruction should be evaluated for this tumor so that it is diagnosed in earlier stages, which will lead to significantly easier surgical management.

Self-assessment

References

  1. Zito J, Fitzpatrick P, Amedee R. Juvenile nasopharyngeal angiofibroma. La State Med Soc. 2001;153:395-398.
  2. Martins MBB, de Lima FVF, Mendonça CA, et al. Nasopharyngeal angiofibroma: Our experience and literature review. Int Arch Otorhinolaryngol. 2013;17(1):14-19.
  3. Panesar J, Vadgama B, Rogers G, Ramsay AD, Hartley BJ. Juvenile angiofibroma of the maxillary sinus. Rhinology. 2004;42(3):171-174.
  4. Blount A, Riley KO, Woodworth BA. Juvenile nasopharyngeal angiofibroma. Otolaryngol Clin North Am. 2011;44(4):989-1004.
  5. Windfuhr JP, Remmert S. Extranasopharyngeal angiofibroma: etiology, incidence and management. Acta Otolaryngol. 2004;124(8):880-889.
  6. Valanzano R, Curia MC, Aceto G, et al. Genetic evidence that juvenile nasopharyngeal angiofibroma is an integral FAP tumour. Gut. 2005;54(7):1046-1047.
  7. Abraham SC, Montgomery EA, Giardiello FM, Wu T-T. Frequent β-Catenin Mutations in Juvenile Nasopharyngeal Angiofibromas. Am J Pathol. 2001;158(3):1073-1078.
  8. Tang IP, Sashinder S, Goapala KG, Narayanan P. Juvenile nasopharyngeal angiofibroma in a tertiary centre: ten-year experience. Singapore Med J. 2009;50:261-264.
  9. Yang PW, Sheen TS, Ko JY, Liu HM, Hsu MM. Nasopharyngeal angiofibroma: A reappraisal of clinical features and treatment at National Taiwan University Hospital. J Formos Med Assoc. 1998;97:845-849.
  10. Onerci TM, Yucel T, Ogretmenoglu O. Endoscopic surgery in treatment of juvenile nasopharyngeal angiofibroma. Int J Pediatr Otorhinolaryngol. 2003;67:1219-1225.
  11. Nicolai P, Berlucchi M, Tomenzoli D, et al. Endoscopic surgery for juvenile angiofibroma: When and how. Laryngoscope 2003;113:775-782.
  12. Mann WJ, Jecker P, Amedee RG. Juvenile angiofibromas: Changing surgical concept over the last 20 years. Laryngoscope. 2004;114:291-293.
  13. Shenoy AM, Grover N, Janardhan N, NJayakumar P, Hegde T, Satish S. Juvenile nasopharyngeal angiofibromas: A study of recurrence pattern and role of pre-Operative embolization - “a decade”S experience’. Indian J Otolaryngol Head Neck Surg. 2002;54(4):274-279.
  14. Ungkanont K, Byers RM, Weber RS, Callender DL, Wolf PF, Goepfert H. Juvenile nasopharyngeal angiofibroma: An update of therapeutic management. Head Neck. 1996;18:60-66.



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