NON-SQUAMOUS CELL NEOPLASMS OF THE LARYNX - RADIOLOGIC-PATHOLOGIC CORRELATION

A variety of benign and malignant non-squamous cell neoplasms may affe ct the larynx. Most of these uncommon laryngeal neoplasms are located beneath an intact mucosa, making diagnosis difficult with endoscopy al one, and sampling errors may occur if only traditional superficial bio psies are performed. In some laryngeal neoplasms, radiologic evaluatio n allows the correct diagnosis. Hemangiomas have very high signal inte nsity at m-weighted magnetic resonance (MR) imaging and strong enhance ment at both computed tomography (CT) and MR imaging after administrat ion of contrast material. Phleboliths, which are pathognomonic for hem angiomas, are easily identified at CT. Chondrogenic tumors typically m anifest with coarse or stippled calcifications at CT. Because of their high water content, chondrogenic tumors have very high signal intensi ty on T2-weighted MR images, whereas only moderate enhancement is obse rved after administration of contrast material. Lipomas typically mani fest at both CT and MR imaging as homogeneous nonenhancing lesions. Th ey are isoattenuating to subcutaneous fat at CT and isointense relativ e to subcutaneous fat with all MR pulse sequences. Metastases from ren al adenocarcinoma typically demonstrate strong contrast enhancement an d now voids at MR imaging, and metastases from melanotic melanoma usua lly have high signal intensity on T1-weighted MR images and low signal intensity on T2-weighted images owing to the paramagnetic properties of melanin. Although radiologic findings are nonspecific in most other non-squamous cell neoplasms of the larynx (eg, Kaposi sarcoma, hemato poietic tumors, tumors of the minor salivary glands, metastases from a melanotic melanoma), cross-sectional imaging can play an important rol e in the diagnostic work-up of these unusual tumors by delineating the extent of submucosal tumor spread and directing the endoscopist to th e appropriate site for the deep, transmucosal biopsies needed to estab lish the diagnosis. In addition, CT and MR imaging are crucial for pos ttherapeutic monitoring and early detection of local recurrence.