primary hydatid cyst of the neck diagnosed by frozen section

Hydatid cyst develops as a slowly growing cyst in patients infected with echinococcosis, which is caused by larval stages of cestodes (tapeworms) of the genus echinococcus, and is also known as hydatidosis. echinococcus granulosus is the most common echinococcus species involving humans. echinococcosis can involve any organ. the liver, followed by the lungs, is the most commonly involved organ. hydatid cyst in the head and neck is so rare that only a few cases have so far been reported. the case reported here is an unusual location of hydatidosis even in countries where echinococcal infection is endemic. she is a 15-year-old girl presenting with asymptomatic cervical cyst. the result of the cervical computed tomography scan was similar to a benign congenital cyst but the frozen section demonstrated a hydatid cyst that was confirmed by final histopathology. we were encouraged to report this case due to the rarity of its location and difference between clinico-radiological presentations and frozen section.