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Paper text:
ewing 's sarcoma ( ews ) is a highly malignant , small , round cell tumor that originated from the primitive neuroectodermal cells , as first described by james ewing in 1921 .
ews of the bone , which most commonly occurs in children and young adults , accounts for approximately 3% of all pediatric cancers and most cases arise in the long bones or the pelvis .
primary ews of the head and neck region is extremely rare , accounting for only 49% of all ewss [ 3 , 4 , 5 , 6 ] .
only 14 cases of ews involving the nasal cavity or the paranasal sinuses have been reported in the world 's otolaryngology literature [ 7 , 8 , 9 ] .
a 23-year - old male visited the otorhinolaryngology department for left purulent rhinorrhea and progressive nasal obstruction for 3 months .
a large vascular polypoid mass was found to completely fill the left nasal cavity and the nasal septum was excluded to the right side ( fig .
ct and mri images showed a large hypervascular mass involving the left nasal airway , maxillary antrum , and anterior ethmoid cells .
there was no bony erosion or contiguous spread , and the remaining sinuses , orbit , and cranial fossa were uninvolved ( fig .
angiography of the left maxillary artery showed deep dyeing of the mass and gelatin was injected into the artery ( fig .
a lateral rhinotomy approach was utilized to gain access to the tumor , followed by dissection along the medial wall of the orbit and around the tumor ( fig .
3c ) . a microscopic analysis revealed an undifferentiated tumor consisting of a solid sheet of small , round blue cells ( fig .
4c ) . molecular studies using pcr confirmed the chromosomal translocation of fli1 ( exon 6 ) ( fig .
adjuvant chemotherapy consisting of vincristine , doxorubicin , and cyclophosphamide alternating with ifosfamide and etoposide ( total : 7 cycles ) was commenced .
radiation therapy was also administered for local control ( total dose : 50.4 gy ) ( fig . 6 ) .
ews is a highly malignant , small , round cell tumor that originates from the primitive neuroectodermal cells .
there is a slightly male predominance with a male - to - female ratio of 1.5 : 1 [ 7 , 10 , 11 ] .
primary ews of the head and neck region is extremely rare and accounts for only 49% of all ewss [ 3 , 4 , 5 , 6 ] . in general , approximately 2030 of ews patients present with metastases at the time of their diagnosis [ 12 , 13 , 14 , 15 , 16 ] .
patients with ews of the head and neck region less frequently have metastases at diagnosis [ 3 , 4 , 9 , 17 , 18 , 19 , 20 ] . in our case
microscopically , these tumors are composed of uniform small round cells with round nuclei containing fine chromatin and scant clear or eosinophilic cytoplasm . in the sinonasal tract ,
the differential diagnosis includes all tumors that are composed of small round cells , such as olfactory neuroblastoma and undifferentiated carcinoma .
the essential diagnostic examination to differentiate ews from the many small round neoplasms is the cd99 marker , which can be detected in a specific immunohistochemical examination . in addition ,
molecular studies using pcr to detect the characteristics of chromosomal translocation are definitive for the diagnosis of ews . a gene sequence , t(11;22)(q24;q12 ) , which results in the fusion of the ews gene with the fli gene , is a specific genetic hallmark of ews [ 22 , 23 , 24 ] . in our case ,
in general , the treatment of ews consists of induction chemotherapy , followed by local control , which usually involves surgical resection , possibly followed by radiotherapy , and subsequent adjuvant chemotherapy . aside from the patient characteristics ,
local control also affects outcome [ 13 , 25 ] . in ews of the extremities , surgical resection ( with or without radiotherapy )
surgery should be combined with additional radiotherapy in cases involving a marginal resection and/or poor histological response .
local control is followed by adjuvant chemotherapy . in many cases , this approach is not practical for patients with ews of the head and neck . in our case ,
the patient also received radiation therapy for local control ( total dose : 50.4 gy ) .
the patient remains alive without evidence of recurrence or metastasis at 3 years since the first examination .
a 23-year - old male presented with a 3-month history of left purulent rhinorrhea , progressive nasal obstruction , and intermittent epistaxis . 
 a fiberoptic examination revealed a large vascular polypoid mass completely filling the left nasal cavity . 
 ct and mri scans showed a large hypervascular mass involving the left nasal airway , maxillary antrum , and the anterior ethmoid cells . 
 there was no bony erosion or contiguous spread , and the remaining sinuses , orbit , and cranial fossa were uninvolved . 
 the patient underwent complete removal of the mass via an external lateral rhinotomy approach . 
 the soft mass was large and vascular . 
 a microscopic analysis revealed an undifferentiated tumor consisting of a solid sheet of small , round blue cells . 
 mitotic figures were also present . 
 immunohistochemically , the tumor cells were strongly positive for cd99 . 
 molecular studies using a pcr confirmed the chromosomal translocation of fli1 ( exon 6 ) . 
 these findings were considered diagnostic for ewing 's sarcoma . 
 postoperatively , the patient was treated with combined chemotherapy and radiotherapy . 
 adjuvant chemotherapy consisting of vincristine , doxorubicin , and cyclophosphamide alternating with ifosfamide and etoposide ( total : 7 cycles ) was commenced . 
 he also received radiation therapy for local control ( total dose : 50.4 gy ) . 
 the patient is currently alive without any evidence of recurrence or metastasis .