Introduction Malignant sinonasal
tumors comprise less than 1% of all
neoplasms. A wide variety of
tumors occurring primarily in this site can present with an undifferentiated or poorly differentiated morphology. Among them are
esthesioneuroblastomas, sinonasal
undifferentiated carcinomas, and
neuroendocrine carcinomas. Objectives We will discuss diagnostic strategies, recent advances in immunohistochemistry and molecular diagnosis, and treatment strategies. Data Synthesis These lesions are diagnostically challenging, and up to 30% of sinonasal
malignancies referred to the University of Texas MD Anderson
Cancer Center are given a different diagnosis on review of pathology. Correct classification is vital, as these
tumors are significantly different in
biological behavior and response to treatment. The past decade has witnessed advances in diagnosis and therapeutic modalities leading to improvements in survival. However, the optimal treatment for
esthesioneuroblastoma,
sinonasal undifferentiated carcinoma, and
neuroendocrine carcinoma remain debated. We discuss advances in immunohistochemistry and molecular diagnosis, diagnostic strategies, and treatment selection. Conclusions There are significant differences in prognosis and treatment for
esthesioneuroblastoma,
neuroendocrine carcinoma, and
sinonasal undifferentiated carcinoma. Recent advances have the potential to improve oncologic outcomes but further investigation in needed.