Helical CT with Virtual Endoscopy of a Laryngeal Chondroma

Abstract

A 65-year-old man had hoarseness and dyspnea. A CT scan showed a cartilaginous tumour of the subglottic larynx appearing as a submucosal calcified neck mass with cartilaginous matrix extending into the airway. Chondromas and chondrosarcomas are rare, accounting for less than 1% of all laryngeal neoplasms. The distinction between chondromas and chondrosarcomas is a histologic diagnosis that may be difficult, particularly in well differentiated neoplasms.

Often tumours initially reported as chondromas have recurred as low-grade chondrosarcomas. On direct laryngoscopy, cartilaginous tumours of the larynx are usually submucosal and are covered by intact laryngeal mucosa. The intact mucosa was identified on CT scans in this case. Radiographic examinations are useful, and coarse calcification is identified on plain films in most cases.

CT is useful in assessing the tumour's origin and extension and is more sensitive that plain films in identifying the characteristic calcifications. In the absence of metastasis, radiographic investigation is unable to differentiate benign chondroma from low-grade chondrosarcomas. Surgery is the treatment of choice for laryngeal chondromas and chondrosarcomas. Radio- and chemotherapy have in general been ineffective.