Low-Grade Non-intestinal Type Sinonasal Adenocarcinoma: A Case Report.

Sinonasal non-intestinal-type adenocarcinomas represent a rare subset of head and neck cancers with distinct pathological and clinical characteristics. Patients usually present with nasal obstruction, epistaxis, and rhinorrhea. The diagnosis is established through histopathological examination. The treatment of choice is complete surgical excision with or without radiotherapy. We report a case of low-grade non-intestinal type sinonasal adenocarcinoma in a 65-year-old male patient. Nasal endoscopy showed a left-sided grade 4 polyp based on Meltzer classification, which is attached to the left middle turbinate. Computed tomography of the paranasal sinuses showed a polyp in the superior part of the left nasal cavity compressing the left middle turbinate with obliteration of the left sphenoethmoidal recess. Initial biopsy results were inconclusive, and the patient underwent complete surgical excision of the mass along with anterior and posterior ethmoidectomy. Excisional biopsy results showed strong positivity for SOX10, S100, and DOG1, indicating seromucinous differentiation. Six months post-operatively, the patient is doing well with no clinical or radiological signs of recurrence. In conclusion, this case underscores the importance of timely diagnosis and comprehensive surgical intervention in managing low-grade non-intestinal type sinonasal adenocarcinomas, ultimately contributing to improved patient outcomes and highlighting the need for further research in this rare cancer subtype.