Oral involvement of sinonasal undifferentiated carcinoma: A case report and immunohistochemical study of a challenging case

Author(s)

Goncalves, Jussara Maria ; Scarini, Joao Figueira ; Gondak, Rogerio ; Altemani, Albina ; Mariano, Fernanda Viviane

• Document type: Journal article
• Source: Oral Oncology; v. 126, p. 3-pg., 2022-02-18.

Abstract

Introduction: Sinonasal undifferentiated carcinoma (SNUC) is a rare tumor highly aggressive most frequently arise in the maxillary sinus and nasal cavity. Oral involvement is extremely rare. Case report: A 62-years-old male presents a large infiltrative mass involving the hard palate and left alveolar ridge. Computed tomography showed bone destruction and invasion of paranasal sinuses and orbits. Histology revealed a malignant neoplasm consisting of small round cells with minimal cytoplasm and hyperchromatic nuclei without any connection with the oral mucosal epithelium. Immunohistochemical analysis showed epithelial origin (CK-7+, CK-20+, AE1/AE3+, EMA+) and lacked strong evidence of squamous and neuroendocrine differentiation (p63-, 34 beta E12- , NSE-/+, chromogranin-, synaptophysin-). TTF-1 negative ruled out the metastatic origin. A diagnosis of SNUC subtype positive for SMARCB1 (INI1) was reached. The patient was submitted to concurrent radiotherapy and chemotherapy without signs of recurrence after 2 years. Conclusion: SNUC involving the oral cavity is a rare malignancy that may mimic symptoms of dental infection or sinusitis. A careful correlation of clinical, microscopic, and immunohistochemical characteristics is mandatory for early diagnosis. (AU)

• FAPESP's process: 15/07304-0 - Study of genetic and metabolic changes of pleomorphic adenoma and carcinoma ex pleomorphic adenoma by exome, gene expression and immunohistochemistry
• Grantee: Fernanda Viviane Mariano Brum Corrêa
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 19/09419-0 - Genomic alterations in the malignant transformation of the Pleomorphic Adenoma
• Grantee: João Figueira Scarini
• Support Opportunities: Scholarships in Brazil - Doctorate