Arise from lipoblasts and not preexisting lipomas. Branchial Cleft Cyst Probably most common congenital cystic neck mass. Often found in age groups ranging from teens to forties. Often noticed when they become infected. Usually located at anterior lateral neck just under the sternocleidomastoid muscle.
Common location is actually at the angle of the mandible.
Usually arise from second branchial cleft. Can be located as far inferiorly as the supraclavicular level. If cyst is found in the external ear canal or parotid gland, this most likely represents a first branchial cleft cyst. Branchial cleft cysts are generally unilocular and thin walled unless they become infected. Sebaceous Cyst Can be quite large and may have mixed signal characteristics depending upon composition.