Hilda Elie Stambuk MD, Presenter: Nothing to Disclose

1) Review the imaging features of benign and malignant sinonasal tumors. 2) Understand the role and specific utility of imaging modalities in the diagnosis of sinonasal tumors. 3) Learn the imaging characteristics of pathways of spread of malignant sinonasal tumors. 4) Understand important imaging features relevant to treatment and post-treatment surveillance of sinonasal tumors.

Tumors of the paranasal sinuses and nasal cavity are rare, constituting only about 3% of all upper respiratory tract tumors. The majority of patients present with non-specific symptoms and radiologists are often challenged to make the clinician aware of the potential for an ominous disease process such as a malignant tumor. It is therefore crucial to understand the role of imaging modalities such as CT, MRI and PET scan in order to optimize the benefits of imaging against the risks of misdiagnosis. Contrast-enhanced CT in axial and coronal planes is an excellent initial study for evaluation of sinus neoplasms because bone destruction is more easily seen on CT. Ear¬ly stage tumors present as unilateral masses that gener¬ally do not densely enhance on CT. Bony destruction is a common feature of squamous cell carcinoma (SCC), whereas regressive remodeling of adjacent bone occurs more fre¬quently in benign and less aggressive lesions. Most tumors have low to intermediate signals on T1W MRI. Because they generally are highly cellular with little water content, they have intermediate signal on T2W images and are therefore easy to differ¬entiate from postobstructive sinus secretions, which are hyperintense on T2W MRI. Some minor salivary gland tumors, schwannomas, and inverted papillomas have sufficient water content and can be bright on T2W MRI. Postcontrast T1W MRI is particularly important in iden¬tifying dural/intracranial extension of tumors. PET scan is the first-line modality in monitoring patients after therapy because of very high negative predictive value. False-positive results can however occur because of infection, inflammation, and early treatment-related changes that take up to 3 months to resolve. This lecture will discuss the salient features of common benign sinonasal tumors and illustrate the anatomic patterns of spread for malignant tumors including perineural spread.

Stambuk, H, Sinonasal Tumors.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14000619.html