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Immunohistochemical analysis of growth mechanisms in
juvenile nasopharyngeal angiofibroma.
Eur Arch Otorhinolaryngol. 2007 Apr;264(4):389-94.
Angiogenic
factors are discussed to participate in growth and promotion of
juvenile nasopharyngeal angiofibroma (JNA). However, only few data
are available and mechanisms remain unclear. In the presented study
we analysed the expression and subcellular distribution of several
angiogenic growth factors and receptors potentially involved in JNA-growth
and -vascularisation. In a retrospective, descriptive, multicenter-study,
we analysed 13 formalin-fixed, paraffin-embedded or cryopreserved
JNA-tumors (eleven primary tumors and two recurrent ones) after
immunohistochemical staining. We used monoclonal antibodies specific
for transforming growth factor beta 1 (TGF-beta(1)), basic
fibroblast growth factor (bFGF), the VEGF-receptors 1 and -2 (FLT-1
and FLK-1), and the hypoxia inducible factor (Hif-1alpha). Data were
compared to the vessel density. Quantitative analysis of staining
intensities was performed by a computer assisted quantification
technique. Endothelial and stromal compartments of the samples were
analysed separately. Data were compared to vessel densities and
patients data. The VEGF-Receptor-2 (FLK) was frequently unregulated
in the stroma and endothelium of those samples with high vessel
densities. Similarly, we observed high bFGF- and TGF-beta(1) levels
in the stroma of strong vascularised samples. No correlations of
expression levels to patients' data were found. The reported data
support the concept of JNA-growth and -vascularisation driven by
factors released from stromal fibroblasts. Therefore, inhibition of
these factors might be beneficial for the therapy of inoperable JNA.
Juvenile
nasopharyngeal angiofibroma: a revised staging system.
Rhinology.2006 Mar;44(1):39-45.
OBJECTIVES:
To discuss the shortcomings of current staging systems and to
suggest modifications according to new surgical methods and data.
STUDY DESIGN: A retrospective chart review. METHODS: The medical
records of 36 patients, all of whom underwent resection of juvenile
nasopharyngeal angiofibroma by external or endonasal approach
between 1983 and 2002, were reviewed retrospectively. Follow-up
period of patients ranged from 3 to 7 years (mean, 4.5 years).
Tumour extent, sites and rate of persistent disease were analyzed
and compared with the literature. RESULTS: Persistent or recurrent
disease was found in 12 of the 36 patients (33%). The primary tumour
of these 12 cases invaded one or more anatomic region beside
nasopharynx: the base of the pterygoid process in 9 cases (75%), the
infratemporal fossa in 4 (33%), the pterygomaxillar fossa in 4
(33%), and the sphenoid sinus in 2 cases (17%). Involvement of the
pterygoid process base was observed in only 3 of the 24 patients
without persistent disease, whereas it was found 10 out of 12
patients with persistent disease. CONCLUSIONS: Advances in
radiographic imaging, embolization, and surgical methods of treating
angiofibromas have changed the sites associated with a high risk for
persistent disease or morbidity. These changes have made it
necessary for the authors to devise more appropriate classifications
and, subsequently, several new staging systems were gradually
introduced. Recent technological advances, particularly angled
endoscopes, have resulted in improved exposure. In the light of all
these recent advances, data from our series, and the literature, we
suggested a new classification for determining the risk of
persistent disease, choosing the appropriate surgical method, and
for maintaining uniformity.
Juvenile
nasopharyngeal angiofibroma: stage and surgical approach.Nippon
Jibiinkoka Gakkai Kaiho. 2005 May;108(5):513-21.
Juvenile
nasopharyngeal angiofibromas (JNAs) are benign tumors that
occasionally invade the pterygopalatine fossa, infratemporal fossa,
or middle cranial fossa. Several surgical approaches have been used
based on the location of the tumor, including transpalatal,
transmaxillary, and lateral rhinotomy, midfacial degloving, and Le
Fort type I osteotomy. We reviewed 4 cases of JNA that had been
treated by resection in the Department of Otolaryngology of
Kagoshima City Hospital and 31 cases of JNA reported in the Japanese
literature between 1990 and 2003. We analyzed the outcome of the
surgical treatment of JNA in these cases to identify the surgical
approaches that were most effective in removing tumors at several
different stages. Radkowski staging showed that 17 (48.6%), 2
(5.7%), 4 (11.4%), 9 (25.7%) and 3 (8.6%) patients had stage IA, IB,
IIA, IIC, and IIIA tumors, respectively. A transpalatal approach was
employed in 11 cases (31.4%), a transmaxillary approach in 9 cases
(25.7%), a transnasal approach in 6 cases (17.1%), and other
approaches, (25.7%). The recurrence rate was, 5% in the stage I
cases, 38% in the stage II cases, and 33% in the stage III cases.
The transpalatal approach was followed by a high recurrence rate in
the cases of stage II and higher stage. Several factors are critical
when choosing the surgical approach to JNA: adequate exposure of the
tumor, ability to control bleeding, prevention of postoperative
facial deformity, and avoidance of interference with growth of the
face.
Juvenile
angiofibroma. Ugeskr Laeger. 2005 Aug 22;167(34):3163-6.
Juvenile
angiofibroma is a rare, benign, rich vascular tumor, and
approximately one new case is diagnosed in Denmark each year. It
sits in the foramen sphenopalatinum and occurs in boys from 14 to 25
years of age. The most frequent initial symptoms are nasal
obstruction and epistaxis. Through the years, the treatment of
juvenile angiofibroma has included many methods, including surgical
excision, electrocoagulation, interstitial or external radiation
therapy, cryosurgery, hormone administration and chemotherapy.
Radiation, chemotherapy and surgery have proven to be the most
effective treatments. The most serious complication has been
preoperative bleeding, but since the introduction of preoperative
particle embolization the blood loss has been greatly reduced.
Today, surgery preceded by embolization is the primary standard
treatment. It is important to diagnose the tumor early, when radical
surgery is easier and the frequency of recurrence is lower.
Juvenile
nasopharyngeal angiofibroma.An
Otorrinolaringol Ibero Am.
2005;32(4):361-71.
Juvenile
Juvenile nasopharyngeal angiofibroma (JNA) is a benign and highly
vascular tumor. In this article we present a case treated in our
institution. We present form of presentation, exploration and
intra-arterial pre-operative embolization by neuroradiology, and the
treatment with the Le Fort technique. JNA has a complex anatomy,
high recurrence and special histopathology, therefore the surgery is
very complex and as an with high morbidity. The pre-operative
embolization has decrease the hemorragic complications. We review
the literature the of the JNA nowadays.
Vessel density,
proliferation, and immunolocalization of vascular endothelial growth
factor in juvenile nasopharyngeal angiofibromas.Arch
Otolaryngol Head Neck Surg. 2004 Jun;130(6):727-31.
BACKGROUND:
Juvenile nasopharyngeal angiofibroma (JNA) is a rare, highly
vascularized neoplasm of the nasopharynx that affects boys and young
men. The underlying dysregulated molecular mechanisms remain
unclear. The participation of angiogenic growth factors has been
suggested, but few studies have been published. OBJECTIVES: To
evaluate the expression and localization of vascular endothelial
growth factor (VEGF), proliferating cells, and vessel density in JNA.
STUDY DESIGN: Immunohistochemical examination of 10 consecutive JNAs
(8 primary tumors and 2 recurrent tumors). METHODS:
Paraffin-embedded and cryopreserved JNA samples were included. VEGF-,
CD31-, and Ki67-specific antibodies were applied and visualized
using light microscopy. Vascularization was determined by counting
CD31-positive vessels. Proliferating and VEGF-expressing vessels as
well as stromal cells were quantified by the same method. Patients'
age at the time of surgery and tumor stage were correlated with the
immunohistochemical data. RESULTS: All tumors were heavily
vascularized, but major differences were noted between the samples.
About half of the vessels were proliferating (Ki67 positive) and
half of the Ki67-positive cells were also VEGF positive. The tumor
stroma was VEGF positive in 8 of 10 samples and proliferating in 5
of these 8. The 5 samples with both VEGF- and Ki67-positive stroma
showed high vessel densities. No correlation was observed between
age or tumor stage and vessel density, VEGF expression, or Ki67
expression. CONCLUSIONS: In JNA, VEGF is frequently expressed by
stromal cells and vessels and is associated with proliferation and
increased vessel density. We suggest the promotion of
vascularization by VEGF, but the involvement of androgens in JNA
angiogenesis still needs to be analyzed.
Juvenile
nasopharyngeal angiofibroma presenting as Foster Kennedy Syndrome.
Ethiop Med J.2001 Jul;39(3):251-60.
Juvenile
nasopharyngral angiofibroma (JNA) is a rare benign tumor of the
nasopharynx that occurs in adolescent boys with epistaxis and nasal
obstruction. It may grow into the cranium causing elevated
intra-cranial pressure and compression on the optic nerve. A
histological-proven case of JNA in an 18 year-old Ethiopian boys is
presented. He became blind due to optic atrophy in the right eye,
but salvaged a useful vision in the left eye radiotherapy. The
possibility of Foster-Kennedy Syndrome, a presentation of one
atrophic and one papilloedematous optic nerve head of bilateral
asymmetric optic atrophy, is discussed. Controversies about its
histological appearance, natural history, diagnostic methods and
management modalities are reviewed. JNA should be considered in
adolescent boys who present with optic atrophy and/or nasal mass.
Early detection and initial surgical treatment with adjunct
radiotherapy could have prevented visual loss on this boy.
Nasopharyngeal angiofibroma: true neoplasm or vascular malformation?
Adv Anat Pathol. 2000 Jan;7(1):36-46.
Nasopharyngeal angiofibromas (NA) are rare tumor-like lesions
characterized by architecturally irregular vessels set in a fibrous
stroma. The unique morphology, the strong predilection for male
adolescents, and the uncertainty about its etiology contributes to
significant confusion regarding the classification of NA, which
still has not been solved today. Based on immunohistochemical and
electron microscopic examinations, we demonstrate in detail the
various unusual vascular architectural features of NA. They
represent discontinuous vascular basal laminae, focal lack of
pericytes, and pronounced irregularity of the smooth muscle layers.
In thick smooth muscle layers and pads, the orientation of muscle
cells is frequently disturbed, and the individual cells differ in
size and shape. Occasionally, the muscle layers disperse
peripherally into individual cells, creating the impression of
vessel-independent smooth muscle cells within the stroma. The
summation of all morphological irregularities demonstrated in this
paper allows the conclusion that NA represent vascular
malformations.
Expression of
CD34-antigen in nasopharyngeal angiofibromas.Int
J Pediatr Otorhinolaryngol. 1998 Aug 1;44(3):245-50.
Formalin-fixed,
paraffin-embedded and frozen tissues of 24 patients with primary
nasopharyngeal angiofibroma, of whom seven had recurrences, were
studied immunohistochemically for the expression of CD34 antigen
using two different antibodies (HPCA-1 and QBEND 10). In all cases,
there was an exclusive staining of endothelial cells, while
pericytes, smooth muscle cells and stromal fibroblasts were not
reactive. The staining intensity, however, was more pronounced in
small tumor vessels of capillary- and sinusoidal-type than in larger
vessels, which were usually characterized by an irregular smooth
muscle coat. This differential staining indicates an increased
proliferative potential of the endothelium of the small vessel
component of nasopharyngeal angiofibroma (neoangiogenesis) and an
inhibitory influence of vascular smooth muscle cells on endothelial
cell growth. Moreover, the positive immunoreaction of all
endothelial cells for CD34 is indicative of the absence of lymphatic
vessels, which confirms previous ultrastructural observations. No
differences in the staining pattern were observed between primary
versus recurrent tumors, formalin fixed, paraffin embedded versus
snap-frozen acetone fixed material, or between both CD34 antibodies.
Our findings indicate that nasopharyngeal angiofibroma is a
vasoproliferative malformation.
Juvenile
nasopharyngeal angiofibroma: diagnosis and treatment.Otolaryngol
Head Neck Surg. 1987 Dec;97(6):534-40.
Juvenile
nasopharyngeal angiofibroma (JNA) is an uncommon, histologically
benign vascular tumor that occurs almost exclusively in adolescent
males. While occasional mention is made of the occurrence of JNA in
females and in older males, only four cases have withstood rigorous
clinicopathological review. This neoplasm accounts for less than
0.05% of all benign lesions that originate in the nasopharynx. Its
clinically malignant behavior is a result of its propensity for
locally destructive growth and fatal hemorrhage. The evolution in
the management of these tumors has been the subject of much interest
and much confusion. The advents of computed tomographic (CT)
scanning, selective angiography with embolization, and refinements
in surgical approaches have revolutionized operative management of
these lesions by allowing more realistic selection of surgical
candidates, better preoperative planning, and more flexible (yet
aggressive) primary surgical treatment. The attendant reduction in
morbidity and mortality of contemporary surgical management of this
disease has largely obviated the argument of those who advocate use
of radiotherapy as the primary treatment modality for this benign
lesion. This latter view is based on the reports of massive
hemorrhage, significant incidence of incomplete removal, and
mortality reported in the older surgical literature. This article
details our experience with a series of 31 patients who had
clinicopathological diagnoses of JNA and were treated between 1954
and 1984. It furthermore represents an update of our previously
reported series.
Juvenile
nasopharyngeal angiofibroma. A 30 year clinical review.Am
J Surg. 1983 Oct;146(4):521-5.
Thirty-one patients with juvenile nasopharyngeal angiofibroma
treated at Memorial Sloan-Kettering Cancer Center from 1949 to 1979
were reviewed. Eighteen of the patients were previously untreated
and in the other 13, previous treatment elsewhere had failed. Median
follow-up was 54 months. All the patients were male adolescents
whose presentations were characterized by epistaxis (73 percent) and
nasal obstruction (60 percent). The tumors invariably arose within
the nasal cavity or nasopharynx and involved neighboring structures
in 58 percent of the patients. Treatment included surgery (30
patients), radiotherapy (13 patients), the administration of
androgens (11 patients), sclerotherapy (2 patients), and cryotherapy
(1 patient). Of the 18 primary patients, 14 were managed surgically
with irradication of disease in 12 (86 percent). Of the four primary
patients initially treated nonsurgically, disease recurred in three,
all of whom were rendered free of disease by surgical excision. Of
the 13 secondary patients, 8 were free of disease after surgery
only, and 2 were free of disease after multimodal therapy with
surgery being the last treatment employed. There were no deaths.
Maxillary radionecrosis (one patient) and facial cellulitis (three
patients) constituted the only significant morbidity. This study has
demonstrated the clinical characteristics of juvenile nasopharyngeal
angiofibroma and supports the primary role of surgical excision in
its management.
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