Unusual location of a second branchial cleft cyst presenting in the suprasternal notch

Background Second branchial cleft cysts (SBCCs) are congenital benign tumors that comprise up to 90% of all branchial cleft anomalies. SBCCs typically present in the lateral neck along the anterior border of the upper third of the sternocleidomastoid muscle. We describe a case of a SBCC presenting in an unusual location in the lower neck close to midline. Methods An 18-year-old male presented with a 2-year history of a neck mass in the suprasternal notch. Imaging findings were reviewed with a head and neck radiologist who felt that the findings were highly suggestive of a fourth branchial cleft cyst. Results The patient underwent surgical excision of the mass. Final pathologic evaluation confirmed the diagnosis of a second branchial cleft cyst. Conclusions Though extremely uncommon, second branchial cleft cysts can extend to the suprasternal notch and should not be excluded from the differential diagnoses of lower neck masses.