1st City Clinical Hospital, Minsk, Belarus.

Synonyms

Cystic hygroma.

Definition

Cystic hygromas are benign congenital malformations of the lymphatic system that results in formation of cysts in various locations. The cysts may be unilocular or multilocular and of variable size [1].

Case report

A 31-year-old woman (G4P2) with non-contributive history was referred to our hospital at term for delivery. Ultrasonographic examination found a tumorous mass of the fetal neck consisting of multiple cystic structures. Our presumed diagnosis was cervical lymphangioma. The mass reached from cervical region into mediastinum. Moreover, a persistent left superior vena cava was also noticed.

The newborn was delivered via cesarean section and the findings were confirmed. The sclerotherapy of cervical masses was performed twice at the age of seven and eight month.

Images 1, 2: The images show cervical region of the fetus with multiple cystic structures of the lymphangioma (arrows).

Images 3, 4: The images show transverse scan of the fetal chest at the level of the heart with persistent left superior vena cava.

Videos 1, 2:  Video 1 shows cervical region of the fetus with multiple cystic structures of the lymphangioma. Video 2 shows transverse scan of the fetal chest at the level of the heart with persistent left superior vena cava.

Video 3: Video shows postnatal echocardiography with mediastinal part of the lymphangioma and dilated coronary sinus.

Etymology

Hygroma in Greek means water-containing tumor [2].

Prevalence

According to some publications the frequency is approximately 70-75:10,000  pregnancies [3, 4].

Etiology

Unknown.

Pathogenesis

In the eighth week of gestation, six lymphatic sacs can be identified in developing embryo (two jugular sacs, two iliac, one at the base of mesentery and one localized dorsally to the abdominal aorta - cisterna chyli).  Later a network of lymphatic vessels develops connecting lymphatic sacs of various regions. During the ninth week of gestation, these sacs are invaded by connective tissue to form lymph nodes. There were a few mechanisms proposed to explain the pathophysiology of cystic hygromas. There are a number of proposed mechanisms to explain the pathophysiology of cystic hygroma. Embryologically, these lesions are believed to originate from sequestration of lymphatic tissue from lymphatic sacs, during the development of lymphaticovenous sacs. These sequestered tissues fail to communicate with the remainder of the lymphatic or venous system. Later on, dilatation of the sequestered lymphatic tissues ensues, resulting in the cystic morphology of these lesions [5]. Lymphangiomas are usually classified as capillary, cavernous or cystic lymphangiomas. Cystic hygroma occurs more frequently as compared to other types of lymphangioma, and may compose of single or multiple macrocystic lesions having scarce communication with normal lymphatic channels. Approximately 75% of lymphangiomas occur in the neck, generally in the posterior triangle, and 3–10% extend into the mediastinum. Less than 1% of all lymphangiomas are purely mediastinal [6]. Cervicothoracic lesions are not uncommon in children. All cervicothoracic lesions except superficial lesions extend from the neck to the thorax through the thoracic inlet. The thoracic inlet is the junction between the neck and thorax and is delineated by the Sibson fascia, which extends bilaterally from the transverse process of C7 to the medial border of the first rib. Lymphangioma is the most common cervicothoracic mass in children [7].

Sonographic findings

Ultrasound of the lesion usually features multicystic mass with internal septations and no blood flow is detected on color Doppler ultrasonography.

Implications for targeted examination

As cervico-mediastinal lymphangioma surrounds vital structures of the neck and mediastinum it’s important for postnatal management to define extent of the lesion. Fetal karyotype analysis and thorough echocardiography should be performed.

Differential diagnosis

Lymphangioma may resemble anterior mediastinal lesions such as lymphoma, thymoma, hemangioma and cystic teratoma. There were a few reports of assessment of the lesions by ultrasound, magnetic resonance and computed tomography falsely considering mature teratomas as lymphatic malformation (cystic hygromas). Consequent histological assessment revealed mature teratomas. Inability to distinguish between lymphatic malformation and teratomas by these imaging modalities points out a risk of incorrect treatment of these lesions by sclerotherapy [8, 9].

Associated anomalies Lymphangiomas may be isolated findings or associated with Turner’s syndrome, Noonan’s syndrome, familial pterygium colli, alcohol syndrome and trisomies [10].

Prognosis

In cases of successful surgical resection prognosis is good. As the lesions originate from cervical or supraclavicular locations they often cannot be removed completely because of the proximity of vital structures and thus recurrence is common [11]. Cases associated with hydrops have poor prognosis.

Recurrence risk

Not increased.

Management

Obstetrical management depends on the size of external part of lymphangioma. Small lesions do not alter usual obstetrical management. In large lesions a cesarean section is required. After birth different treatment approaches are used. Cases with facial, laryngeal, pharyngeal or mediastinal extensions are not easily treated Their complete surgical removal is often impossible and thus, recurrence may occur. Although surgical excision has been considered to be the treatment of choice by most of the surgeons, sclerotherapy of lymphangiomas has gained popularity during recent years. Sclerotherapy may also be used as additive therapy in large or mixed forms of lymphangiomas [12].

References

1. Manikoth P, Mangalore GP, Megha V. Axillary cystic hygroma. J Postgrad Med 2004;50:215-6.

2. Mirza B, Ijaz L, Saleem M, Sharif M, Sheikh A. Cystic hygroma: An overview. J Cutan Aesthet Surg 2010;3:139-44

3. Gedikbasi A, Gul A, Sargin A, Cevlan Y. Cystic hygroma and lymphangioma: associated findings, perinatal outcome and prognostic factors in live-born infants. Arch Gynecol Obstet 2007;276(5):491-8

4. Gedikbasi A, Oztarhan K, Aslan G, Demirali O, Akyol A, Sargin A, Cevlan Y. Multidisciplinary approach in cystic hygroma: prenatal diagnosis, outcome, and postnatal follow up. Pediatr Int 2009;51(5):670-7

5. Jung E, Won HS, Lee PR, Lee IS, Kim A, Nam JH The progression of mediastinal lymphangioma in utero.Ultrasound Obstet Gynecol. 2000; 16(7):663-6

6. Fonkalsrud EW. Lymphatic disorders. In: Grosfeld JL O'Neill JA Jr, Coran AG, Fonkalsrud EW, Caldamone AA. editors. Pediatric surgery. 6 th ed. Chicago: Mosby Elsevier; 2006.p.2137-45.

7. Castellote A, Vazquez E, Vera J, Piqueras J, Lucaya J, Garcia-Pena P, Jimenez JA. Cervicothoracic lesions in infants and children. Radiographics 1999; 19(3):583-600

8. Bhutta MF, Ching HY, Hartley BE. Cervico-thoracic teratoma masquerading as lymphatic malformation. J Laryngol Otol. 2006; 120(11):955-8

9. Ro EY, Thomas RM, Isaacson GC. Giant dermoid cyst of the neck can mimic a cystic hygroma: using MRI to differentiate cystic neck lesions. Int J Pediatr Otorhinolaryngol. 2007; 71(4):653-8

10. Meza MP, Denson M, Slovis TL. Imaging of mediastinal masses in children. Radiol Clin North Am 1993; 31:583-604.

11. Brown LR, Reiman HM, Rosenow EC 3rd, Gloviczki PM, Divertie MB. Intrathoracic lymphangioma. Mayo Clin Proc 1986; 61(11):882-92.

12. Sanlialp I, Karnak I, Tanvel FC, Senocak ME, Buyukpamukcu N. Sclerotherapy for lymphangioma in children. Int J Pediatr Otorhinolaryngol 2003; 67(7):795-800.