Epignathus

Boris M. Petrikovsky, MD, PhD, Frank Chervenak, MD, Dieter M. Schapfel, MD

Address correspondence to: Boris M. Petrikovsky, MD, PhD. Department of Obstetrics and Gynecology, North Shore University Hospital—Cornell Medical Center, 300 Community Drive, Manhasset, NY 11030-3801 Ph: 516-562-2892 Fax: 516-562-3624

Synonyms: Oral teratoma, nasopharyngeal teratoma, extragonadal teratoma, facial teratoma.

Definition: A teratoma which arises from the oral cavity and/or the pharynx.

Incidence: Teratomas, being the most common neoplasms in the newborn, occur at a rate of 0.3:10,000 live births¹. About 2% of all pediatric teratomas occur in the nasopharyngeal area.

Etiology: Abnormal migration of primordial germ cells which settle in the mediastinum, neck, nasopharynx, and brain (pineal and hypothalamic regions).

Pathology: Teratomas have at least one tissue type from each of the three embryonic layers. The cystic or multicystic components are usually accompanied by solid areas that often have a brain-like tissue quality.

Associated anomalies: Associated anomalies are seen in approximately 6% of these cases² and include facial clefts, bronchial cysts, hypertelorism, and congenital heart defects.

Diagnosis: Complex heterogeneous mass arising from the fetal mouth and/or nose. Hyperextension of the head has also been reported.

Differential diagnosis: Cystic hygromas which are predominantly in the lateral and posterior neck regions.

Prognosis: Nasopharyngeal teratomas are often associated with polyhydramnios, nonimmune fetal hydrops, and exophthalmos. These tumors are rarely malignant but can be fatal due to the local mass effect (i.e. respiratory compromise). Most cases reported in the literature revealed dismal outcome^4-6.

Recurrence: None known.

Management: In early diagnosis, the option to terminate the pregnancy can be offered. If the fetus is viable, a cesarean section as a route of delivery is the best option. A pediatric surgeon and neonatologist should be present at the time of delivery to provide immediate resuscitation, endotracheal intubation and even a tracheotomy if an airway cannot be secured.

MESH Palatal-neoplasm; Teratoma BDE 0283 CDC 239.200 ICD9 744.8

Introduction

The prenatal diagnosis of epignathus has been described in the literature^4,5,8,9. Little is known, however, about the possible sequelae and natural history of this disease. We present a case in which epignathus was associated with abnormal intracranial anatomy and cardiac failure.

Case report

A 30-year-old woman G₆P₄ was referred to the Fetal Assessment Unit because of polyhydramnios and inability to adequately assess fetal anatomy. The patient"s pregnancy course and medical history were noncontributory. The ultrasound examination revealed a singleton fetus in oblique lie. Polyhydramnios and placentomegaly were noted. The measurements of BPD, abdominal perimeter and femur length were compatible with 22 weeks of pregnancy. A complex mass, originating from the fetal mouth and measuring 56 x 49 x 28mm, was visualized (fig. 1).

Figure 1: Epignathus with cystic and solid components (between arrows).

A mild pericardial effusion was detected. The echocardiographic findings included dilated right atrium, mitral and tricuspid regurgitation and decreased fractional shortening of the ventricles. The liver was enlarged (vertical measurement was 37 mm; normal: 28 + 1.5 mm). The intracranial anatomy was distorted and indicative of ventriculomegaly (fig.2).

Figure 2: Hydrocephalus in fetus with epignathus.

The diagnosis of epignathus was made, and the patient elected pregnancy termination. A 700g stillborn was delivered with a length of 20cm. The autopsy showed a spherical, exophytic palatine mass which protruded from the mouth and was attached to the hard palate in the midline (fig. 3).

Figure 3: Frontal and lateral view of stillborn at autopsy. The large epignathus deforms the facial anatomy and blocks the upper airways and the mouth.

The external fetal deformities included caudal displacement of the mandible and cephalad distortion of the nose and face. Multiple bone-like structures could be visualized on the X-ray of the stillborn (fig. 4).

Figure 4: X-ray of stillborn at autopsy. Numerous bones within epignathus are less mature than those of the infant itself.

Dissection of the tumor through its mid-hard palatine insertion revealed that the tumor extended through the nasal cavity into the cranium. The tumor was detected in both the temporal and posterior fossae on the right side. A large degree of ventricular enlargement was seen in the brain. Histologic sections revealed variable teratomatous tissue differentiation. These included primitive lung, skin, fibrovascular tissue, primitive intestinal structures, immature pancreas, immature neural tissue, cartilage and bone. The cytogenetics of the teratoma revealed a 46 XY normal male complement of chromosomes. The massive hepatomegaly and pericardial effusion were noticed.

Examination of the placenta revealed classical hydrops. The placenta weighed 500g and grossly showed flattening of the placental lobules.

Discussion

Synonyms

Synonyms include oral teratoma, nasopharyngeal teratoma, extra- gonadal teratoma, facial teratoma.

Definition

A teratoma which arises from the oral cavity and/or pharynx.

Incidence

Teratomas, being the most common neoplasms in the newborn, occur at a rate of one in 35,000 live births. About 2% of all pediatric teratomas occur in the nasopharyngeal area.

Etiology

The midline location of most congenital teratomas has served to support the hypothesis that primordial germ cells migrate along the dorsal midline from the hindgut-yolk sac region into the embryonic genital ridge. Some cells continue their cephalad migration to eventually settle in the mediastinum, neck, nasopharynx, and brain (pineal and hypothalamic regions).

Pathology

Most teratomas have at least one tissue type from each of the three embryonic layers. Regardless of the primary site, teratomas have several pathologic features in common. The cystic or multicystic components are usually accompanied by solid areas that often have a brain-like tissue quality. Hemorrhage is inconspicuous, with the exception of those tumors subjected to trauma during delivery. Tumor-related necrosis is usually minimal because these neoplasms are rarely malignant.

Associated anomalies

Associated anomalies are seen in approximately 6% of these cases² and include facial clefts, bronchial cysts, hypertelorism, and congenital heart defects.

Diagnosis

The prenatal diagnosis of epignathus is based on the sonographic visualization of a complex mass emanating from the fetal mouth and/or nose. The solid areas are composed of tissues of different density; they may also include calcific areas of tooth and bone. Hyperextension of the head has been reported in fetuses with epignathus. The ultrasound diagnosis is based on the detection of the mass arising from the fetal face. Polyhydramnios is usually present secondary to the obstruction of fetal mouth and inability to swallow. Our particular interest in this case is the development of fetal heart failure, as evidenced by hepato- and placentomegaly as well as fetal echocardiographic changes. Fetal heart failure and mechanical occlusion of the fetal mouth by the tumor are probable contributors to the development of polyhydramnios in this case. The mechanism of fetal heart failure in cases of epignathus is probably similar to the one in fetal sacrococcygeal teratomas: high output cardiac failure.

Prognosis

Nasopharyngeal teratomas are often associated with polyhydramnios, nonimmune fetal hydrops, and exophathalmos. Although the majority of these tumors are benign in nature, fetal and neonatal death is very common due to the local mass effect, which produces life-threatening dysfunction (basocranial teratomas) or cessation of function (respiratory compromise from a nasopharyngeal or cervicothyroidal lesions). Most cases reported in the literature revealed dismal outcome^4-6.

Differential diagnosis

Epignathus should be differentiated from cystic hygromas, which are often located in the neck area. Both lesions can be associated with nonimmune hydrops fetalis. Cystic hygromas are located outside fetal cranial and facial structures, predominantly in the lateral and posterior neck regions.

Recurrence

No cases of epignathus occurring in subsequent pregnancies were described in the literature. Nasopharyngeal tumors are rare and comprise only two percent of all neonatal teratomas.

Management

In those cases where the lesions were diagnosed early in the course of pregnancy, parents should be informed of the guarded prognoses and offered an option to terminate the pregnancy.

If the fetus is viable at the time of diagnosis, most authorities advise a cesarean section as a route of delivery. A pediatric surgeon and an experienced neonatologist should be present at the time of delivery to provide immediate resuscitation, endotracheal intubation and even a tracheotomy if an airway cannot be secured.

Conclusion

In conclusion, both distorted intracranial anatomy and heart failure may further complicate prognosis and outcome in fetuses with epignathus and should be included as potential complications during patient counseling.

References

1. Barson AJ. Congenital neoplasia: The society experience. Arch Dis Child 53:436, 1978.

2. Gilman PA: Epidemiology of human teratomas. In Damjanov I, Knowles BB, Solter D (Eds): The Human Teratomas. Experimental and Clinical Biology. Clifton, New Jersey, Humana Press, 94, 1983.

3. Stocker JT, Dehner LP (Eds). Pediatric Pathology. 328-33, JB Lippincott Co, Philadelphia, 1992.

4. Chervenak FA, Tortora M, Moya F, et al: Antenatal sonographic diagnosis of epignathus. J Ultrasound Med 3:235-7, 1984.

5. Kaplan C, Perlmutter S, Molinoff S. Epignathus with placental hydrops. Arch Pathol Lab Med 104:374-5, 1980.

6. Romero R, Pilu G, Jeanty P, et al: Prenatal Diagnosis of Congenital Anomalies. Appleton & Lange, Norwalk, 106-8, 1986.

7. Chervenak FA, Isaacson G, Lorber J. Anomalies of the fetal head, neck, and spine. Ultrasound Diagnosis and Management. WB Saunders Co, Harcourt Brace Jovanovich, Inc., Philadelphia, 39-51, 1988.

8. Nogales FA, Gasca L, Llamas R, et al: Epignathus: clinical, radiological, and pathological considerations. Int J Gynecol Obstet 15:41-3, 1977.

9. Kang KW, Hissong SL, Langer A: Prenatal ultrasonic diagnosis of epignathus. JCU 6:330-1, 1978.