British Journal of Oral and Maxillofacial Surgery (1986) 24, 272-276 0 1986 The British Association of Oral and Maxillofacial Surgeons

EPIGNATHUS (CONGENITAL TERATOMA OF THE HARD PALATE): A CASE REPORT

M. A. K. ZAKARIA, F.R.C.S.

Department of Surgery, College of Medicine, Mosul, Iraq

Summary. A rare case is described of congenital teratoma protruding from the mouth (epignathus) attached to the hard palate in an infant of 3 days. Typical teratoma components and brain tissue were noted. A description of the relevant clinical and pathological features is given and the embryological basis for the aetiology of the lesion is discussed. The literature is reviewed.

Introduction

Epignathus is a rare congenital malformation. The infant with this tumour is born with a mass of tissue protruding from the mouth. It is a teratoma consisting of a mixture of tissues originating from all the three germinal layers, which are not usually found at the tumour’s site of origin. There are a number of hypotheses on the origin of teratoma, but none of them adequately explain the peculiarities and differing locations of these tumours (Ashley, 1973).

The various explanations include the suggestion that they represent incomplete attempts to form a Siamese twin, or that they are resting places of totipotential cells left behind during embryogenesis. Another theory is that germ cells may give rise to teratomas by parthenogenetic development. Teratomas may be considered as either gonadal or extragonadal tumours. Since the gonads develop from retro- peritonial tissue, all the tumours in this area may arise by parthenogenesis of haploid cells, probably by fusion of two such cells. Hence there would be enough cytoplasm and organising potential for the development of tissues from all germ layers (Ashcraft & Holder, 1974). The extragonadal sites, including the sacral area, mediastinum, face, neck and cranium, are areas where Siamese twins may be joined (Ashcraft & Holder, 1974). In these areas, incomplete division of the blastula may provide enough cells for the production of a teratoma but insufficient for a complete twin.

Regardless of their origin, teratomas must be regarded as both developmental anomalies and tumours.

Other birth defects are often found in children with teratomas; Ashcraft and Holder (1974) described a family in which presacral teratoma, and stenosis of the anus and sacral defects were attributed to an autosomal trait.

Case Report

A 3 day-old Iraqi baby girl was referred having been born with a huge mass protruding from her mouth, which caused considerable difficulty with feeding. The baby was delivered at home with no difficulty. There was no family history of any similar abnormality. All of the mother’s other children (three boys and four girls) are in good health and have no abnormality.

The baby’s general health was good, she was not cyanotic, and there was no

(Received 5 April 1984; accepted 3 January 1986)

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EPIGNATHUS 273

Fig. 1

Fig. 2

Figure l-Large epignathus in a 3 day-old infant. Figure 2-Profile view of the same case.

difficulty with breathing; no other deformity or abnormality was detected on detailed examination.

The mass protruding from the mouth was bigger than an orange, globular in shape, covered with normal skin, of soft fleshy consistency, did not enlarge or become tense when the child cried, and did not transilluminate. Near the base of the mass, a cap-like bluish red structure, softer than the rest of the mass was noted, incompletely surrounding a short cartilaginous pedicle. The pedicle was connected to the hard palate in the midline (Figs. 1 & 2). X-ray of the skull revealed no abnormality in the vault or sella turcica.

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Fig. 5

Fig. 7

Figure 5-Microscopic section of the epignathus showing nervous tissue. Figure &Microscopic section showing rosettes, pseudoglandular formation. Figure 7-Nerve tissue and cartilage. Figure &Hair follicles and epidermoid structures.

Figure SPost-operative picture showing the site of attachment of the epignathus to the hard palate in the midline. Figure

&The epignathus after excision.

Fig. 4

Fig. 8

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Under general anaesthesia excision was performed and bleeding was controlled by diathermy. There was no C.S.F. leakage from the site of excision. The infant started to suck with some difficulty, but soon improved (Figs. 3 & 4).

Histopathology showed different types of tissues, of the three germinal layers, typical of a teratoma (Figs. 5, 6, 7 & 8).

Discussion

Epignathus is a misnomer, for the term should etymologically be reserved for tumours arising from the jaw, but it is commonly applied to teratomas of the mouth in the newborn.

Ehrich (1945) preferred to classify them according to their site of origin episphenoideus, epipalatus, or epuranus, and epignathus. Willis (1962) regards these lesions as being of two distinct types: first, the true neoplasm, a teratoma consisting of multiple tissues foreign to the part in which they arise and secondly, ‘the hamartoma, a congenital malformation composed exclusively of components derived from the local tissues (Willis, 1968).

Most epignathi are attached to the base of the skull in the posterior nasopharynx, near the site of Rathke’s pouch and the closed craniopharyngeal canal. The tumour in one reported case was associated with an open Rathke’s pouch which in turn was associated with the cranial vault (Wilson & Gehweiler, 1970).

Epignathus may vary from a large mass involving the palate and sphenoid, which presents at the mouth at birth and constitutes an immediate threat to life, to a small pedunculated tumour, which is easily removed. Survival after excision of basicranial teratoma in the newborn is rare and only three cases have been recorded up to 1970 (Bennett, 1970).

In 1971, Tuson reported a case of basicranial epignathus, which was among the very few cases surviving after surgery.

In 1977 Bhargava and Singh reported a case of basicranial teratoma who survived only a few hours after excision.

In the presented case, in spite of the huge mass protruding from the mouth the infant was born alive, and passed the immediate threat to life during delivery because the tumour was attached to the hard palate only, which is relatively rare, with no extension to the nasopharynx nor brain.

The mother had no difficulty in labour because she was multiparous. The infant had some flattening of the hard palate, and had no other abnormality

in the nasopharynx or elsewhere in the body. In some cases there may be an intracranial extension of the tumour, with bony changes in the sella turcica and abnormalities of one or both parts of the hypophysis. When this occurs, it appears clear that the growth has extended not only outwards into the pharynx and mouth but along the craniopharyngeal canal, entering the cranial vault (Raffensperger, 1980).

When the tumour lies entirely within the nasal or oral cavity, there is often deformity of the maxilla. Even if there is no direct attachment of the tumour to the facial bones, pressure effects will frequently distort the normal structures. The usual facial teratoma causes grotesque distortion and in most cases, airway obstruction. Associated congenital anomalies are frequent and most infants with these tumours are stillborn (Raffensperger, 1980).

In our case the main bulk of the tumour was protruding from the mouth and attached to the hard palate with a short pedicle 2.5 cm. in diameter, for which

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reason the distortion was minimal and with no airway obstruction, which is very rare. In Ehrich’s series only one case was attached to the hard palate; there was suckling and feeding difficulty which improved gradually after excision of the tumour.

The other interesting feature in this case is the presence of brain tissue among the components of the teratoma, a feature which is rarely seen in teratomas.

The child is thriving well and suffering from no other abnormality.

Acknowledgements

I would like to extend my thanks to Dr Ahmad Al-Dabagh of the Department of Pathology for reading the histopathology and for the photographs. and to T. Ah, of the department of Medical Photography.

References

Ashley, D. J. B. (1973). Origin of teratoma. Cancer, 32, 390. Ashcraft, K. W. & Holder, T. M. (1974). Hereditary presacral teratoma. Journal of Pediatric Surgery,

9, 691. Bennett, J. P. (1970). A case of epignathus with long term survival. Brifish Journal of Plastic Surgery,

23, 360. Bhargava, J. S. & Singh, W. (1977). Basicranial teratoma (Epignathus). Journal of the lndian Medical

Associution, (69) 6, 135. Ehrich, W. E. (1945). Teratoid parasite of the mouth (episphenoid, epipalati, epignathi). American

Journal of Orthodontics, 31, 650. Raffensperger, J. G. Swenson’s Pediatric Surgery. (1980) 4th Edition, Crofts/New York, Appleton-

Century, pp. 366-374. Tuson, K. W. (1971). Epignathus: basicranial teratoma. A case report and review of the literature.

British Journal of Surgery. 58, 935. Willis, R. A. (1962). The Borderland of embryology und Pathology. 2nd Ed. p. 442. London:

Butterworths. Willis, R. A. (1968). Some unusual developmental heterotopias. British Medical Journal, 3, 267. Wilson, J. W. & Gehweiler, J. A. (1970). Teratoma of the face associated with a patent canal extending

into the cranial cavity (Rathke’s pouch) in a three week-old child. Journal of Pediatric Surgery, 5, 349.