Shahrekord University of Medical Sciences Journal of Shahrekord University of Medical Sciences 2717-0071 21 6 2019 12 01 Primary hydatid cyst of the neck diagnosed by frozen section 284 286 10.34172/jsums.2019.50 EN Elham Jafari https://orcid.org/0000-0001-9240-9177 Mahdieh Shokrizadeh Mohsen Shahba Journal Article 10.34172/jsums.2019.50 2019 10 19 2019 11 09 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.