A branchial cleft cyst is a congenital lump in the neck, appearing as a fluid-filled sac under the skin. Though present at birth, they may not be immediately noticeable, often becoming apparent in childhood or early adulthood. These benign cysts originate from tissues that did not fully develop or disappear during early fetal growth.
How Branchial Cysts Develop
Branchial cleft cysts originate during fetal development. Around the fourth week of embryonic life, structures known as branchial arches form in the head and neck area. These arches are separated by clefts, essential for forming various tissues.
Normally, these arches and clefts fuse and disappear as the fetus develops, typically around the seventh week. If a cleft fails to close completely, a remnant of tissue can form an epithelial-lined cavity that fills with fluid, resulting in a branchial cleft cyst. Most branchial cleft cysts arise from the incomplete closure of the second branchial cleft.
Signs of a Branchial Cleft Cyst
Branchial cleft cysts often present as a soft, painless mass in the neck. They can be found from near the ear, down the side of the neck, to just above the collarbone, often along the front edge of the sternocleidomastoid muscle. While many cysts are asymptomatic, some may have a small pit or opening on the skin that can intermittently drain fluid, such as clear mucus or pus.
A cyst can become symptomatic if it swells or becomes infected. Signs of infection include pain, redness, warmth, and increased tenderness around the lump. If large or infected, it might cause difficulty swallowing or noisy breathing.
Diagnosis and Treatment Options
Diagnosing a branchial cleft cyst typically involves a physical examination by a healthcare provider, who assesses the location and characteristics of the neck mass. Imaging tests confirm the diagnosis and determine the cyst’s size and extent. An ultrasound is often the initial imaging choice, followed by a computed tomography (CT) scan or magnetic resonance imaging (MRI) for detailed anatomical information, especially if surgery is considered. These scans help distinguish the cyst from other neck masses.
Surgical removal is the primary treatment for a branchial cleft cyst. Surgery is recommended to prevent recurrent infections, address cosmetic concerns, or alleviate symptoms like pain or difficulty swallowing. The procedure involves an incision, usually in a neck skin crease, to carefully remove the cyst and any associated tract. While antibiotics treat active infection before surgery, medical therapy alone cannot permanently resolve the cyst.
Life After Treatment
The outlook for individuals who undergo complete surgical removal of a branchial cleft cyst is generally excellent. Most people recover fully without experiencing long-term problems or complications. Recovery time typically involves returning to normal activities within two weeks following the procedure, though some mild pain, swelling, or bruising in the neck area can occur initially.
While the risk is low, recurrence can happen if any part of the cyst or its associated tract is not entirely removed during surgery. The recurrence rate is estimated to be around 3%, but it can be higher, up to 20%, if there was a history of prior infection or incomplete excision. Follow-up appointments are important to monitor the surgical site and ensure proper healing, providing an opportunity to address any lingering concerns.