Educational Content: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider for diagnosis and treatment.
Definition of Branchial cyst
Medically reviewed by Min Clinic Staff | Updated: January 2026
Branchial cyst: Also called a branchial cleft cyst, this is a cavity that is a remnant from embryologic development present at birth in one side of the neck just in front of the large angulated muscle on either side (the sternocleidomastoid muscle). The cyst may not be recognized until adolescence as it enlarges its oval shape. It may develop a sinus or drainage pathway to the surface of the skin from which mucus can be expressed. Total surgical excision is the treatment of choice. Recurrence is not expected.