Olfactory Neuroblastoma and Olfactory Carcinoma: A Practical Review

Area of Science:

• Pathology
• Oncology
• Head and Neck Surgery

Background:

• The sinonasal tract harbors two primary tumors originating from neuroectodermal differentiation: olfactory neuroblastoma (ONB) and olfactory carcinoma (OC).
• ONB is characterized as a keratin-negative neoplasm with a lobulated architecture and variable neurofibrillary matrix.
• OC, a recently identified entity, features keratin-positive neuroectodermal cells often interspersed with glandular structures.

Purpose of the Study:

• To provide a comprehensive overview of the clinical and diagnostic characteristics of ONB and OC.
• To elucidate the key features that differentiate ONB and OC from each other and from other sinonasal small round blue cell tumors.
• To offer practical guidance for accurate diagnosis and differential diagnosis in the sinonasal tract.

Main Methods:

• Literature review focusing on clinical presentation, histopathological findings, and immunohistochemical profiles of ONB and OC.
• Comparative analysis of diagnostic criteria for ONB, OC, and other relevant sinonasal neoplasms.
• Discussion of overlapping features and potential diagnostic pitfalls.

Main Results:

• ONB and OC are distinct neuroectodermal tumors with differing keratin expression and architectural patterns.
• Both entities can present with overlapping features, necessitating careful evaluation.
• Differential diagnosis must consider other neuroendocrine-expressing small round blue cell tumors of the sinonasal region.

Conclusions:

• Accurate distinction between ONB and OC is crucial for appropriate patient management.
• Understanding the specific histopathological and immunohistochemical markers is essential for diagnosis.
• This review serves as a practical guide for clinicians and pathologists managing sinonasal neuroectodermal tumors.