CASE 17736 Published on 31.07.2022

Sino-nasal Ewing’s sarcoma


Head & neck imaging

Case Type

Clinical Cases


Likhith N., Ruchir Jyani, K.M. Mahendra, A.K. Chaturvedi, Sunil Kumar Puri

Department of Radiology, Rajiv Gandhi Cancer Institute and Research Centre, India


29 years, female

Area of Interest Head and neck, Oncology ; Imaging Technique CT
Clinical History

A 29-year-old female had nasal blockage and epistaxis for 10 months and was diagnosed with a right nasal polyp. She had sinus surgery, which revealed undifferentiated carcinoma on histology. A referral to our institute was made, and a clinical examination revealed a right nasal crust with no palpable cervical lymph nodes.

Imaging Findings

Pre-op-NECT-Isodense lesion in the right nasal cavity indenting the nasal septum, right middle, and inferior turbinate with the erosion of the septum (Figure 1). Post-operative MRI showed a residual T1 hypointense, T2 intermediate, diffusion restricting, heterogeneously enhancing lesion involving the anterior part of the ethmoid sinus, predominantly involving the left ethmoid air cells, the upper part of the nasal septum, and extending superiorly through the cribriform plate and eroding fovea ethmoidalis extending into the medial part of the left frontal sinus and bilateral basifrontal region (left > right) with mild dural enhancement (Figure 2, 3, 4 and 5). The lesion showed avidity on FDG PET-CT (Figure 6). No evidence of distant metastasis was seen.


Ewing's sarcoma is a malignant primary bone tumour of the small round cell type that most usually affects children and adolescents, affecting the extremities and trunk. It accounts for around 4-6 percent of all primary bone tumours, with a slight male predominance. Head and neck cancer affects only 1-4 percent of people, and sino nasal cavity cancer is much rarer [1, 2, 3, 8, 9]. Because tumours involving the nasal cavity and paranasal sinuses present with non-specific symptoms such as epistaxis, rhinorrhea, and nasal obstruction, they have large differentials compared to cancers involving other locations, making diagnosis challenging [3,9]. At the time of diagnosis, distal metastasis to the lungs and bones is common, accounting for 15–30% of patients.

Histologically, these tumours show small blue round cells arranged in sheets, cords, and nests [9]. Ewing’s sarcoma and primitive neuroectodermal tumour are linked to chromosomal t(11;22) (q24; q12) translocation (balanced translocation) congruous to EWSR1/FLI-1 fusion, which is a new diagnostic tool [4, 6, 7, 9].

Imaging findings include permeative-osteolysis with periosteal reaction and mineralization of the matrix on CT; extraosseous tumour extension on MRI is a sign of malignancy. MRI and CT are used for surgical planning to map the extent of disease and as a baseline imaging study. PET-CT scans are used in conjunction with MRI for surgical planning, staging, assessing therapeutic response, and restaging [6, 7, 11].

There are few standardized treatments and follow-up protocols in management, with chemotherapy and radiotherapy being the first-line treatments, particularly for larger tumours [5, 7, 9]. Survival increases in patients whose tumour resection was completely achieved before chemotherapy [9].

A review of the right nasal mass sample of our patient showed a poorly differentiated malignant round cell tumour and IHC revealed that the tumour cells were positive for CK, P40, NKX2.2, synaptophysin, and CD99 while negative for myogenin, CK5, EBER-ISH, and chromogranin, and a differential between Ewing sarcoma and poorly differentiated squamous cell carcinoma was favoured. Later, the FISH analysis revealed an EWSR1 gene rearrangement signal in 50% of the cells, and a final diagnosis of Ewing’s sarcoma was made. The patient had neoadjuvant chemotherapy, and MRI and PET-CT scans revealed a considerable decrease in tumour mass, indicating a partial response. She had endoscopic craniofacial excision and reconstruction subsequently. Histopathology found that less than 1% of the residual viable tumour. The patient is currently undergoing adjuvant radiotherapy and chemotherapy, with PET-CT and MRI scans showing no signs of recurrence.

Written informed consent was obtained from the patient.

Differential Diagnosis List
Sino-nasal Ewing’s sarcoma
Squamous cell carcinoma
Adenoid cystic carcinoma
Final Diagnosis
Sino-nasal Ewing’s sarcoma
Case information
DOI: 10.35100/eurorad/case.17736
ISSN: 1563-4086