Clinical case of intranasal Ewing sarcoma

Background. Malignant tumors of the nasal cavity and paranasal sinuses (PNSs) rank second and third, respectively, inincidence among the upper respiratory tract tumors. Over 500 patients are diagnosed with the nasal cavity, nasopharyngeal,PNS, and frontal skull base malignancies every year in the Russian Federation. Primary diagnosis of this group of diseasesis difficult due to the anatomic and topographical features, late development of the main symptoms, low cancer awarenessamong primary care physicians. Among the upper respiratory tract malignancies, the group of low-differentiated sinonasalcancers, as well as the Ewing sarcoma family tumors are of special interest not only because of their rarity, but alsobecause of the specifics of their morphology and clinical manifestations.Ewing sarcoma of the ethmoidal labyrinth is a rare and aggressive tumor that predominantly affects children and adolescents.It arises in bone or soft tissue, often in the pelvis, ribs, and extremities. The main cause of Ewing’s sarcoma is a mutation inthe genes responsible for regulating cell growth. Symptoms may include local pain, swelling, and systemic manifestationssuch as fever and weight loss. Diagnosis involves imaging techniques such as multi-slice computed tomography, andbiopsy, including immunohistochemical and genetic studies to determine the tumor type and stage. The treatment isgenerally combined and includes chemotherapy, surgical intervention, and radiotherapy. The prognosis depends on thestage at the time of diagnosis, as well as the response to treatment. Current research aims to improve treatment methodsand increase the survival rates.
Сlinical case. In this article, we discuss the classification, diagnostic options, verification features, and treatment of thistumor on the example of a patient with Ewing’s sarcoma located in the nasal cavity who was treated in the ENT Departmentof the First Pavlov State Medical University, St. Petersburg. The patient underwent successful surgical treatment viaendoscopic endonasal access, followed by over a year of chemotherapy. The patient regularly undergoes follow-up CTand MRI scans, and no signs of recurrence have been detected. The remission has lasted for more than 2 years.
Conclusion. Ewing sarcoma of the nose and PNSs is an extremely rare condition. Currently, only a few clinical cases ofsuccessful surgical treatment of intranasal Ewing’s sarcoma with subsequent mono-chemotherapy have been documentedin the literature. Due to the similarity in morphology and clinical manifestations with esthesioneuroblastoma, the initialdiagnostics is often challenging. A definitive diagnosis can only be established after the molecular genetic testing. Allpatients suspected of having a nasal cavity tumor are recommended to undergo contrast-enhanced multi-slice computedtomography. The five-year survival rate with this approach exceeds 90%, with a low risk of progression and recurrence.
Keywords: malignant tumor, Ewing sarcoma, olfactory neuroblastoma, endoscopy, nasal cavity, electromagneticnavigation system, immunohistochemistry, tumor, endonasal approach, computed tomographyConflicts of interest. The authors have no conflicts of interest to declare.
Funding. The authors declare no funding for this study and have not received any grants to complete the studyAcknowledgement. The authors would like to acknowledge the support of the university for providing resources andassistance during the study.