Although uncommon in the United States, echinococcosis is very common in parts of Africa and Asia. A more chronic form of the disease may present with fibrous nodules. Small, thin-walled cysts and cavities can also be created when small nodules soften and then cavitate as the contents are expectorated. Cysts and cavities average 2 to 4 cm in diameter. Cavities are thick walled, as would be expected, because they result from central necrosis of a growing mass.
Hematogenous metastases can also cavitate.
When there are many metastases, at times only some cavitate. Cavitation has been reported in many different types of metastatic disease but occurs more frequently in squamous cell cancers that originate in the head and neck, cervix, or skin than in adenocarcinomas. Clinical features vary greatly and relate to the sites of involvement. Systemic symptoms include fever, malaise, and weight loss. Upper airway findings include rhinorrhea, sinus pain and drainage, nasal and nasopharyngeal ulcers, and otitis media.