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angioleiomyoma or vascular leiomyoma is a rare benign tumor formed by smooth muscle cells in the vascular wall or by remnants of embryonic tissue , commonly found in the uterus ( 95% ) , skin ( 3% ) , and gastrointestinal tract ( 1.5%).1 
 2 
  less than 1% of all vascular leiomyomas occur in the nasal cavity.3 
 4 hachisuga et al describe only 48 cases ( 8% ) of angioleiomyoma in the head and neck in a study with 562 cases .
only 5 of the 48 cases were located in the nasal cavity , accounting for 1% of all angioleiomyomas.5 
  maesaka et al reported the first case of angioleiomyoma in the nasal cavity in 1966.6 only 30 cases have been documented in english in the literature .
forty - nine additional cases have been reported in the japanese literature.7 
  the origin of angioleiomyoma of the nasal cavity is uncertain , partly due to the scarcity of smooth muscle in the nasal cavity .
three hypotheses have been proposed for the origin of smooth muscle tumors in the nasal cavity : from aberrant undifferentiated mesenchymal cells ; from elements of smooth muscle in the walls of blood vessels and of piloerector muscles ; or from both previous hypotheses , simultaneously.2 
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 13 some articles indicate that sexual hormones and epstein - barr virus infection can affect the genesis of nasal angioleiomyoma.3 
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  the literature shows a prevalence of angioleiomyomas of the nasal cavity in female patients ( in a 2:1 ratio between females and males ) between the fourth and sixth decades of life , and affecting mainly the inferior nasal conchae.7 
 9 these angioleiomyomas develop in the mucosa of the nasal cavity as single solid small cutaneous masses
. they can be painful or not and can expand.4 
 12 they usually manifest as epistaxis ( 56.25% ) and with nasal obstruction ( 56.25%).11 
  computed tomography ( ct ) and magnetic resonance do not conclude the diagnosis .
surgical excision with histologic examination is the only way to make a definite diagnosis.4 in addition to that , conventional light microscopy studies for the identification of angioleiomyoma after staining with hematoxylin - eosin can be performed using special staining , such as masson trichrome stain , or immunohistochemical markers such as smooth muscle actin , desmin , myoglobin , s-100 protein , and vimentin .
the treatment of choice is total lesion excision.2 
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 13 recurrence is extremely rare after total excision . in this report , we present the case of a 49-year - old woman with a diagnosis of angioleiomyoma of the nasal cavity .
a 49-year - old woman was referred to the department of otolaryngology and head and neck surgery of a tertiary hospital , in october 2008 , with complaints of nasal obstruction and formation of scabs in the left nasal cavity for 12 years .
in addition , pain and bulging in the external region of the nasal ipsilateral cavity were mentioned . on physical examination and anterior
rhinoscopy , a reddish mass was observed obstructing the whole left nasal cavity and vestibule , associated with a bulging in the left paranasal region .
nasofibroscopy showed the presence of a reddish intracavitary sessile lesion in the inferior nasal concha , which occupied the whole left cavity and prevented the progression of the nasofibroscope .
the cavum area was unobstructed . given the clinical condition , a ct scan of the facial sinuses , biopsy of the lesion , and preoperative tests were ordered . the ct scan showed the presence of an oval lesion of soft tissue density that measured 2 cm in its longest axis , exhibited heterogeneous enhancement after injection of endovenous contrast , and was located in the left nasal cavity , in the transition between the cartilaginous and the bone parts of the nasal septum , in close contact with the latter ( fig .
1 ) . the histopathologic examination showed a squamous papilloma with keratinization of the superficial mucosa without atypias , which confirmed the need to excise the lesion . 
 computed tomography of the skull in axial ( a ) and coronal ( b ) sections , showing oval lesion of soft tissue density measuring 2 cm in its longest axis and located in the interior left nasal cavity , in the transition between the bone and cartilaginous parts in the nasal septum in contact with the structure .
an incision was performed in the lateral mucosa of the left nasal cavity until the lesion was observed and pericapsular tissues were removed for total excision of the lesion .
a nasal plug was inserted and a portion of the specimen was sent for anatomopathologic analysis .
the anatomopathologic result showed an irregular portion of brownish tissue of firm and elastic consistence measuring 1.6    1.5    1.1 cm .
microscopy revealed a benign lesion composed of multidirectional bundles of neoplastic smooth muscle cells with interspersed thick - walled vessels .
( a and b ) histologic sections : angioleiomyoma composed of bundles of neoplastic smooth muscle with interspersed thick - walled vessels ( hematoxylin and eosin , 100   ) .
there was no report or signs of epistaxis . during the outpatient follow - up ,
leiomyomas of the nasal cavity are located in the nasal conchae , septum , paranasal sinuses , vestibule , and cavity floor.12 histologically , the vascular type is composed of bundles of relatively organized smooth muscle cells with interspersed thick - walled vessels .
it is rarely included in the differential histopathologic diagnosis.4 other tumors of the nasal cavity are : nasal angiofibroma , hemangioma , inverted papilloma , malignant lymphoma , fibromyoma , leiomyoblastoma , hemangiopericytoma , angiosarcoma , angiomyolipoma , and vascular leiomyosarcoma.10 
  in the present case , the clinical diagnosis , which was based on anamnesis , physical examinations , and complementary tests , presented low sensitivity and reproducibility . during the assessment ,
a diagnosis of inverted papilloma was suggested , which required complementary tests for confirmation , according to the literature 's scientific guidelines .
the ct helped delineate and correlate the anatomical planes , surgical margins , and characterization of the intranasal mass ; however , it did not provide specific conclusions .
the preoperative biopsy did not coincide with the postoperative histologic study , because the total excision of the lesion ( providing more and better - quality material ) facilitates the anatomopathologic analysis .
the surgical excision combined with the histologic study is the only way to make a definite diagnosis in these cases.4 depending on the extension and location of the lesion , its excision may be performed via endoscopy,2 
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 12 ktp532 laser,2 or open surgery.2 
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 12 preoperative selective embolization should be considered for hypervascular or large lesions .
the patient did not have any relapse of the lesion during the 30 months of outpatient follow - up .
angioleiomyoma of the nasal cavity is a rare benign tumor that is difficult to clinically diagnose and requires a detailed and invasive investigation .
the complementary tests should guide the diagnostic reasoning ; however , we concluded that it is essential to perform a postoperative anatomopathologic study to make a definite diagnosis of angioleiomyoma of the nasal cavity .
introduction  vascular leiomyoma of the nasal cavity is an extremely rare tumor that represents less than 1% of all vascular leiomyomas . 
 it is more prevalent in women between the fourth and sixth decades , reaching primarily the inferior nasal turbinates . 
 
 objectives  reporting and assisting the systematization of more accurate diagnostic methods in clinical and complementary investigation of vascular leiomyoma in the nasal cavity 
 . 
 resumed report  we present the case of a 49-year - old woman diagnosed with vascular leiomyoma in the nasal cavity , which manifested mainly with nasal obstruction . during investigation , 
 computer tomography was not diagnostic , the cytologic study was not conclusive , and according to the biopsy , it was a squamous papilloma . 
 
 conclusion  we suggest that the technical difficulty in obtaining an adequate amount of material for preoperative biopsy , associated with the topography of the lesion in the vestibular nasal region , may have contributed to changing the postoperative diagnosis . 
 thus , pathologic study of the surgical fragment is the more accurate method for diagnosis .