INTRODUCTION
SMARCB1-deficient sinonasal carcinomas are locally aggressive rare
malignant tumors of the nasal cavity and paranasal sinuses. They
represent only about 1% of total head and neck
malignancies.1,2SMARCB1-deficient sinonasal carcinoma
is also called as integrase interactor-1 (INI-1) deficient
carcinoma.2,3
It was first reported in 2014 and was described as a subset of sinonasal
undifferentiated carcinoma.1,2,4Most of the cases are
present lately when the condition is already locally aggressive at
diagnosis. Probably, the reason for late diagnosis is due to the
similarity of clinical symptoms to other benign conditions. As per our
knowledge, only around 200 cases of SMARCB1 deficient sinonasal
carcinomas have been reported so far in the medical literature and this
is the first case that has been reported from Nepal.5
In this case report, we present a case of SMARCB1-deficient sinonasal
carcinoma in a 54-year-old male with the lesion occupying the right
ethmoid sinus and extending up to the right frontal sinus and nasal
cavity.