Lateral neck cyst

Congenital lateral cyst of the neck is considered a benign neoplasm, which is diagnosed very rarely - only 2-3 cases per 100 diagnoses related to neck tumors. The etiology of the development of a neck cyst has not yet been clarified, although its pathogenesis has been studied for two centuries. To date, all existing versions relate to a violation of the embryogenesis process, that is, congenital defects, fetal development anomalies. The formation of the neoplasm begins at an early stage of pregnancy, the development of the cyst is asymptomatic in 90%, which significantly complicates the timely diagnosis and differentiation of a lateral benign tumor from similar diseases of the neck.

In most cases, a lateral cyst is not dangerous, but it is assumed that in a latent, hidden form, inflammation and suppuration, the neoplasm can develop into a malignant tumor.

In the International Classification of Diseases (ICD-10), cysts and fistulas of the branchial cleft belong to block Q10-Q18 – congenital anomalies (malformations) of the face and neck.

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Causes of Lateral Neck Cyst

It is no coincidence that the lateral cyst of the neck received a more accurate name - branchiogenic, closely associated with the most reliable version explaining the appearance of such neoplasms. Branchia are gills, indeed, starting from the fourth week of gestation, the so-called branchial apparatus is formed in the embryo. It includes five pairs of specific cavities (branchial pockets), gill slits and connecting arches (arcus branchialis). Moving along the ventrolateral plane, the cells of the tissues of the branchial apparatus form the basis for the formation of the maxillofacial region of the baby. If there are failures in this process, the branchial arches are not completely obliterated, leaving cavities and openings, in these areas a cyst and an accompanying fistula can develop. The cyst consists of ectodermal tissue, and the fistula is made of endoderm, the corresponding tissue of the pharyngeal pocket.

Types of embryonic branchiogenic disorders:

• Cyst.
• Complete fistula, open on both sides.
• Incomplete fistula with one exit.
• Combination of lateral cyst and fistula.

Most often, the causes of a lateral neck cyst are associated with rudimentary remnants of the second pocket, which should form the tonsils. Such a cyst in 60-65% is accompanied by a fistula, the external opening of which can exit in any zone along the edge of the sternocleidomastoid muscle, and the fistula itself is located along the carotid artery, sometimes crossing it. A branchiogenic cyst, due to its origin, is localized quite deeply, unlike an atheroma or hygroma, and in most cases is detected in children over 10 years old and adult patients. A lateral fistula is determined earlier - in newborns and children up to 5-7 years old, especially if it is characterized as complete, having two openings, one of which exits into the side of the pharynx, and the second - in the Musculus sternocleidomastoideus zone - the sternum cleidomastoid muscle. In addition, the causes of the lateral cyst also determine its structure; from the inside, the neoplasm consists of multilayered squamous epithelium or cylindrical cells, as well as lymphatic tissue, which is the primary source for the formation of gill arches and pockets.

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Symptoms of Lateral Neck Cyst

The clinical signs of a branchiogenic cyst are not specific and are similar to the manifestations of a median benign neoplasm on the neck. However, unlike a thyroglossal cyst, the symptoms of a lateral neck cyst are more intense, in addition, the branchial tumor is always localized on the side, between the 2nd and 3rd fascia, adjacent to the anterior zone of the sternocleidomastoid muscle.

Symptoms of a lateral neck cyst most often debut as a result of a general infectious inflammatory process or after an injury and may be as follows:

• The cyst may appear as a small, almost imperceptible swelling in the area of the carotid artery (“carotid triangle”).
• When palpated, the lateral cyst feels like an elastic, mobile and painless neoplasm.
• A lateral neck cyst most often increases in size during an acute or protracted, chronic inflammatory process in the body (ARI, ARI, flu).
• The tumor grows and becomes visible to the naked eye, protruding and sometimes reaching 10 centimeters in diameter.
• When a lateral cyst becomes inflamed, a nearby lymph node in the neck may become enlarged.
• The enlarged cyst causes the larynx to shift.
• The cyst can put pressure on the neurovascular bundle and cause intermittent pain.
• Infection of the cyst is accompanied by suppuration and the formation of an abscess.
• The acute form of inflammation of the branchiogenic cyst may be accompanied by phlegmon and corresponding symptoms - general intoxication, increased body temperature, damage to the sternocleidomastoid muscle and immobility of the neck.
• Purulent inflammation of the cyst can provoke spontaneous rupture of the walls and the release of exudate through the fistula.
• A lateral cyst can disrupt the process of swallowing food and cause a feeling of heaviness in the esophagus (dysphagia).
• A large cyst causes speech impairment and makes breathing difficult.
• A gill cyst located in the larynx area can cause a characteristic whistling sound when breathing – stridor.

It should be noted that the clinical manifestations of a branchiogenic cyst depend on its location and size and are often not detected for a long period until the onset of a provoking factor - inflammation or trauma. The scanty symptoms and slow development of the cyst create certain difficulties in its diagnosis, especially in differentiation.

Lateral neck cyst in a child

Branchial cyst of the neck is most often diagnosed in children over 7 years old, in general, congenital anomalies in this anatomical zone are extremely rare and manifest closer to puberty. A lateral cyst of the neck in a young child, especially in newborns, usually has a latent form and does not manifest clinical signs until the impact of a provoking factor - trauma, respiratory infection or general inflammatory process in the body. Some experts associate the onset of symptoms of branchial cysts with typical age periods when hormonal changes occur in the body. Statistical data on this disease are extremely scarce and cannot claim to be objective, clinically confirmed information, however, practicing surgeons note the predominance of boys among patients with branchiogenic cysts.

The development of a cervical cyst in a child is almost always preceded by acute respiratory diseases, less often by influenza. The close connection of the neoplasm with the lymphatic tract facilitates the unimpeded penetration of pathogenic microbes into the cyst cavity, the inflammation of which is accompanied by suppuration in 75% of cases.

Both the enlarged cyst itself and its complications – abscess, phlegmon of the neck – are potentially dangerous. It should be noted that in a quarter of sick children, the primary detection of a branchial cyst was associated with a visit to a doctor about an abscess of the neck. There is also a risk of malignancy of a branchiogenic cyst, although branchiogenic cancer does not occur in childhood, it is diagnosed in male patients after 55 years of age. Nevertheless, given the ability of a lateral cyst to develop asymptomatically for decades, the importance of timely detection of the tumor is indisputable.

In a clinical sense, a lateral neck cyst in a child does not manifest specific symptoms and may not bother him for a long time. Only inflammation and growth of the neoplasm causes problems with eating, painful sensations in the tumor area, difficulty breathing. A large cyst, abscess or phlegmon provokes symptoms of general intoxication of the body, the child's body temperature rises, a whistling sound (stridor breathing) appears, lymph nodes enlarge, nausea and vomiting are possible.

Lateral cysts in children and adults are treated only by surgery outside the acute stage. A purulent cyst is subject to puncturing and anti-inflammatory treatment, then after the signs of acute inflammation subside, it is removed. Operations are performed on children over 3 years old, but cyst removal may be indicated at an earlier age in case of serious complications and a threat to the life of the infant.

A lateral neck cyst is considered more difficult to operate than a median cyst, since the tumor walls are in close contact with the vascular-nerve bundle and are anatomically connected to the carotid artery. However, removal of a lateral tumor with high-precision surgical equipment and instruments does not pose a danger to the child's health. The operation is performed under both general and local anesthesia, depending on the patient's age, the size of the cyst and the presence of a fistula. The recovery period and wound healing take no more than 2 weeks. Since the incision is small and cosmetic, after a few months the suture on the neck is almost invisible, and as the child grows, it disappears altogether.

Diagnosis of lateral neck cyst

Before conducting differential diagnostics of a neck cyst, its localization is determined. A branchiogenic tumor is always located on the side, hence its name - a lateral cyst. Diagnostics of a lateral neck cyst is most often carried out at the time of complication, when the cyst has increased in size and is accompanied by an abscess or phlegmon. On the one hand, the clinical manifestations are obvious, on the other hand, they are similar to the signs of other neck diseases, which can complicate the diagnosis process. In addition, a branchiogenic cyst is anatomically closely associated with the edge of the Musculus sternocleidomastoideus - the sternocleidomastoid muscle, the carotid artery and other large vessels, with part of the hyoid bone, which provokes a simultaneous increase in both the cyst and the lymph nodes during inflammation. Therefore, a lateral cyst is often mistaken for lymphadenitis, its suppuration is often defined as an abscess, accordingly, the treatment is not entirely adequate.

It should be noted that differential diagnostics of lateral neck cysts from other types of congenital cysts is not essential, since all of them, one way or another, are subject to surgical removal. Much more significant is the timely statement of the fact of the presence of a cyst as a benign tumor, specification of its size, shape and the presence of a fistula.

How is a lateral neck cyst detected?

• Collection of anamnesis, including hereditary, since gill anomalies can be transmitted genetically in a recessive manner.
• Examination and palpation of the neck and lymph nodes.
• Ultrasound of the neck.
• Computed tomography of the neck in contrast mode as indicated – clarification of the tumor location, size, consistency of the cavity contents, type of fistula (complete or incomplete).
• Puncture of the cyst according to indications.
• Fistulogram (staining of the fistula tract).

Lateral cyst is differentiated from the following neck diseases:

• Lymphadenitis, including non-specific tuberculous form.
• Dermoid of the submandibular salivary glands.
• Lymphangioma.
• Metastases in thyroid cancer.
• Chemodectoma (tumor of the glomus or vagus nerve).
• Lymphosarcoma.
• Abscess.
• Lipoma of the neck.
• Teratoma of the neck.
• Branchiogenic carcinoma.
• Aneurysm of blood vessels.

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Treatment of lateral neck cyst

The only generally accepted method that involves the treatment of a lateral neck cyst is surgery. Surgical treatment is performed both in hospital and outpatient settings, depending on the following factors:

• The period of diagnosis, determination of the lateral cyst. It is believed that the earlier it is detected, the more successful and effective its treatment is.
• Age of the patient. The most difficult operations are performed on small children under 3 years of age. Such operations are indicated for large cysts that threaten the breathing process and cause general intoxication of the body.
• Tumor size. A cyst is indicated for surgery when its size exceeds 1 centimeter in diameter.
• Localization of the lateral cyst. The closer it is to large vessels and nerves, the more complex and extensive the surgical intervention.
• The cyst is inflamed and suppurating.
• Complications accompanying the development of a cyst. An accompanying abscess or phlegmon requires additional anti-inflammatory treatment.
• A type of fistula that is most often detected during surgical removal of a cyst. An incomplete or complete fistula is difficult to treat, as it has passages that are in close contact with the pharynx, main vessels, and hyoid bone.

When removing a branchiogenic cyst, radical dissection of all fistula tracts, cords, up to a part of the hyoid bone is performed. In some cases, tonsillectomy is performed in parallel. Careful and complete removal of all parts of the cyst leads to a quick result, relapses are possible only in case of incomplete excision of the fistula tract or proliferation of the cyst epithelium into nearby tissues.

Inflamed, suppurating cysts are not operated on, they are preliminarily treated with conservative methods, including antibacterial therapy. After the inflammatory symptoms subside, the remission stage is reached, the cyst can be removed.

Lateral Neck Cyst Removal

Removal of a cyst, including a lateral cyst of the neck, is the most common method of treating benign cystic tumors. Branchiogenic cysts should be operated on as early as possible, without waiting for their inflammation, suppuration and corresponding complications. Even if the pus spontaneously breaks through in the form of an open external abscess, early removal of the cyst helps to avoid the risk of its malignancy. In addition, scars left after opening the abscess significantly complicate the inevitable surgical intervention in the future, since it will be technically more difficult to excise such a tumor.

Removal of a lateral neck cyst involves its radical excision, including the fistula. The more thoroughly all parts of the epithelial tissue of the tumor are removed, the lower the risk of cyst recurrence, the frequency of which is 10 cases per 100 operations. The process of removing gill neoplasms is quite complex, which is explained by the anatomical connection of the cyst with such important parts of the neck and the body as a whole:

• arteria carotis externa - carotid artery.
• nerve nodes.
• venae jugulares - jugular veins.
• hyoid bone.
• musculus sternocleidomastoideus – sternocleidomastoid muscle.
• processus styloideus - styloid process.

During the procedure, it is often necessary to remove part of the os hyoideum - the hyoid bone, and the tonsils, and even resect part of the jugular vein in contact with the fistula. All this indicates the complexity and seriousness of the surgical intervention, although such procedures are classified as "minor" surgery. It should be noted that modern equipment, instruments and new surgical techniques allow removing lateral cysts even in small children, if earlier, just 15 years ago, cystectomy was performed only after 5 years of age, now cysts are excised even in three-year-olds. Maximum anesthesia - local or general anesthesia, minimal trauma during surgery allows patients to recover in the shortest possible time, the cosmetic incision is almost invisible, and the scar quickly dissolves, leaving virtually no trace.

Surgery for lateral neck cyst

Branchiogenic cyst removal surgery is performed on patients starting from the age of 3. The scope of surgical intervention and its duration are determined by the clinical picture of the disease and the results of the diagnostic examination.

Surgery for lateral cyst of the neck is currently not considered complicated, but requires care, since any lagging part of the tumor epithelium can subsequently provoke a relapse, and therefore repeated surgical treatment.

The general scheme of the operation is as follows:

• After preparing the patient, anesthesia is administered, most often tracheal intubation (endotracheal anesthesia).
• A coloring agent is introduced into the fistula to clarify and visualize its course. Less often, a probe is introduced into the fistula, this is indicated for complete fistulas with wide ducts.
• The incision is made along the conventional lines on the skin of the neck, showing the location of collagen connecting bundles (Langer's lines). This ensures minimal trauma to the skin - a cosmetic incision.
• When a fistula is detected, its external opening is cut, and a retaining suture (ligature) is applied to the fistula itself.
• The tissues of the neck are dissected layer by layer until the fistula tract is reached, which is simultaneously determined by palpation.
• The fistula is mobilized, isolated in the cranial direction (upwards, towards the skull, towards the auditory canal), continuing the process through the bifurcation of the carotid artery towards the fossa tonsillaris – the tonsillar fossa. In this area, the fistula is ligated and cut off.
• Quite often, during the removal of a lateral cyst, two incisions are required, which are sutured with small subepidermal sutures after the procedure.
• Bipolar electrocoagulation is used extremely rarely during surgery; it is not recommended for use when removing cysts in small children due to the close anatomical connection between the tumor and the vascular system.
• In complicated cases, with a lateral cyst and fistula localized close to the palatine tonsils, parallel tonsillectomy is indicated.

Surgery for a lateral neck cyst lasts from half an hour to an hour, depending on the patient's age and the complexity of the procedure. After the cyst is removed, antibacterial anti-inflammatory treatment is usually administered, and physiotherapy procedures are prescribed - microcurrents, UHF. Surgical sutures are removed after 5-7 days, and dispensary observation is carried out for a year to prevent recurrence of the process.

Prevention of lateral neck cyst

It is almost impossible to prevent the development of a gill cyst, this is due to the reasons for its origin, that is, to anomalies of intrauterine development. Therefore, prevention of a lateral cyst is obviously a task for geneticists and those specialists who deal with issues of the etiology and pathogenesis of congenital malformations of the embryo. If the cyst is detected in a small child and does not have a tendency to inflammation, enlargement, doctors recommend dynamic observation (examination every three months) until reaching the age of 3 years. Regular visits to an ENT doctor, otolaryngologist is the only way to control the development of a tumor, which should be removed at the first opportunity, thereby eliminating the risk of suppuration and various complications in the form of an abscess or phlegmon. Adult patients should remember that prevention of a lateral neck cyst also consists of its early diagnosis and radical excision, since gill cysts tend to develop into branchiogenic cancer.

The main method that helps to stop the enlargement and inflammation of the lateral cyst in time can be regular medical examination of children and their thorough examination by an otolaryngologist. A benign tumor detected in time is successfully operated, which almost 100% guarantees the neutralization of the risk of a malignant process in the neck area.

Prognosis of Lateral Neck Cyst

In general, the prognosis of a lateral cyst of the neck can be classified as favorable, the risk of developing branchiogenic cancer exists, but in percentage terms it is very small. In addition, to date there is no clear statistical data that could confirm the truth of the cyst's transformation into a malignant tumor, rather its supposed malignancy is associated with untimely diagnosed primary thyroid cancer and other oncopathologies of the neck.

The prognosis for the treatment of a lateral neck cyst is more specific, this branchial anomaly is considered recurrent, and the success rate of radical surgery is 90%, the remaining 10% is due to repeated removal of parts of the cyst or fistula. It should be noted that it is the fistula tracts that are the most difficult to excise even with preliminary staining, this is due to the complex anatomical structure of the neck and the close connection of the tumor with large vessels, lymph nodes, hyoid bone, vascular-nerve bundle, tonsils and facial nerve.

The prognosis of a lateral neck cyst may depend on the following factors:

• Age of the patient.
• Duration of the cyst development period.
• The size of the cyst, its location, proximity to important organs, nerve connections and large vessels.
• The presence of a fistula and its type (complete or incomplete fistula).
• The form of the lateral cyst is inflammation and suppuration.
• The contents of the cyst cavity are exudate or pus.
• The presence or absence of a general inflammatory process, chronic diseases of the body.
• The general health condition of the patient.

Lateral cyst of the neck or branchiogenic benign tumor is a rare congenital anomaly that requires further study both in terms of etiology, pathogenesis, and in the field of new methods of its treatment. Currently, the only available and generally accepted method by which lateral cyst is treated is radical surgery. Perhaps in the near future, new methods of tumor neutralization will appear, including those related to the category of conservative treatment.