Diagnostic Dilemma of a Mature Parapharyngeal Teratoma in an Infant

Abstract

Cervical and parapharyngeal teratomas are rare but possible causes for respiratory distress in neonates. They can also present as cystic masses in the neck and can be clinically indistinguishable from lymphatic malformations. Physicians must be cognizant of teratoma as an alternate diagnosis when faced with a cystic neck lesion that responds poorly to injection sclerotherapy. We present a case of a parapharyngeal teratoma which was initially diagnosed and treated as a lymphatic malformation.from the skull base to cricoid suggestive of a lymphatic malformation ( Figure 1). The patient was referred to a second institution where the scans were reviewed and the diagnosis of a possible lymphatic malformation was confirmed. The patient was then planned for injection sclerotherapy.The child underwent sclerotherapy injection without tissue biopsy in 2 stages with minimal clinical and radiological resolution of the mass over 6 weeks. Initial cytology from aspiration and histology from a postnasal mass biopsy showed non-malignant cells and mucinous material respectively. At one month of age, after a second unsuccessful sclerotherapy injection, he underwent a second postnasal space biopsy, debulking of the nasopharyngeal and oropharyngeal components of the mass and a tracheostomy. Histology was suggestive of nasal glial heterotropia. Surgical excision was then planned. A repeat MRI scan was performed, again showing a large multi-cystic parapharyngeal lesion causing mass effect but without intracranial extension (Figure 2). At this stage, diagnosis of teratoma was also considered as a high possibility. A formal excision was then carried out using a cervical incision at 4 months of age (Figure 3). Final histology showed a mature teratoma. In addition to glial tissue, the specimen sections showed mature adipose tissue, bone with marrow elements, stratified squamous epithelium and skin adnexal structures, respiratory mucosa and focal choroid plexus and cerebellar tissue-features not seen in the previous biopsy.