ARRS 2022 Abstracts


E1897. Investigating the Unknown: A Review of Neuroendocrine Sinonasal Carcinoma
  1. Alejandra Bonilla; Instituto Nacional de Enfermedades Neoplasicas
  2. Marycarmen Flores; Instituto Nacional de Enfermedades Neoplasicas
  3. Zaida Pacheco; Instituto Nacional de Enfermedades Neoplasicas
  4. Marco Laura; Instituto Nacional de Enfermedades Neoplasicas
Small cell neuroendocrine carcinoma of the sinonasal tract is a rare and aggressive tumor. These tumors most often arise in the upper or posterior nasal cavity. It usually appears in elderly people and the most frequent symptoms are nasal obstruction, epistaxis, loss of visual acuity, exophthalmos, local pain, and, (rarely), painful inflammation over the sinuses.

Educational Goals / Teaching Points
The goals of this exhibit are to review the anatomy of the nasal cavity and paranasal sinuses; discuss the clinical and pathological results and the multidisciplinary management of neuroendocrine carcinoma; highlight the imaging findings and diagnostic pearls for the diagnosis of neuroendocrine carcinoma; and review the most common differential diagnoses.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Neuroendocrine carcinoma has a neuroectodermal and epithelial origin, including low-grade carcinoids, atypical intermediate-grade carcinoids, and high-grade small cell neuroendocrine carcinoma. The latter represents the most common histological type and is characterized by aggressive behavior with a high potential for recurrence. No preference for a specific sex, race, or geographic area has been determined, and no association with smoking or radiation is known. The evaluation of images, MRI allows us to better identify the extension of the tumor and the invasion to the adjacent tissues. On noncontrast CT, tumor findings tend to be isodense and, after contrast medium administration, present mild or moderate uptake with hypodense areas, indicating necrosis and cysts. Calcification is uncommon; however, bone erosions are mostly observed. On MRI, the lesions present with poorly defined borders, heterogeneous isointense or hyperintense T2 signals with cystic changes and marked enhancement. The differential diagnosis includes inverted papilloma, squamous cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, lymphoma, and olfactory neuroblastoma.

Sinonasal primary neuroendocrine carcinoma is a rare epithelial neuroendocrine pathology, and the symptoms are nonspecific. CT and MRI images will help us determine bone and soft tissue involvement, as they show bone expansion and erosion.