Content area
Full text
Background
Chondrosarcomas of the hyoid bone are a rare occurrence with only 20 cases reported in the English literature since the early 1970s. Cytopathology of such suprahyoid neck masses without imaging guidance may lead to misdiagnoses with other more common cartilage-containing lesions such as pleomorphic adenoma originating from the submandibular or sublingual glands, as occurred in this case. Therefore, cross-sectional imaging is crucial in the preoperative diagnosis of such lesions. Moreover, in contrast to other more common locations in the head and neck, hyoid bone chondrosarcomas tend to present as painless, often slow-growing palpable masses with no other associated symptoms such as hoarseness, dysphagia, breathing difficulty or enlarged cervical lymph nodes. The paucity of symptoms and signs, and non-aggressive behaviour, may suggest a benign mass, which may lead to a more conservative surgical approach. However, the recommended treatment is wide local surgical excision with total hyoidectomy, to decrease the chance of recurrence and histological dedifferentiation.
Case presentation
A 73-year-old man with a painless palpable mass that had grown in the right submandibular/submental region for over 10 months was referred to our institution. On physical examination, a 5 cm, ovoid-shaped submental mass was detected. Other physical and laboratory assessments were unremarkable.
Investigations
A neck CT was performed, revealing a large and relatively well-defined, multilobulated lesion in the submental and prehyoid regions, measuring approximately 50x40x30 mm ( figures 1 - 3 ). The lesion had a hypodense soft tissue component and exuberant calcifications, with a coalescent ring-and-arc pattern, suggestive of chondroid matrix ( figures 1 - 3 ). The lesion extended into the prelaryngeal space, pushed the floor of the mouth upwards, and was clearly separated from the sublingual gland and from the submandibular glands. The pre-epiglottic space was also preserved.
The lesion was in close contact with the right paramedian region of the body of the hyoid bone where insufflation and rupture of its outer cortical margin could be seen, although tumour growth was predominantly exophytic into the prehyoid region ( figures 1 and 2 ). The remainder of the hyoid bone was normal in size and morphology. Also noted was the anterior displacement of the strap muscles confining the lesion anteriorly.
No cervical lymphadenopathy was seen.
These imaging findings were highly suggestive of a chondrosarcoma...