Definition: This teratoma is composed of tissues foreign to cervical region, with all three germ layers represented.

Prevalence: An uncommon tumor. More than 150 cases have been reported in the literature, however, ultrasound detection was documented in only 14 cases until 1994.

Etiology: Theories regarding the origin of these teratomas include derivation from totipotential germ cells or abnormal development of conjoined twins.

Ultrasound features: The tumor appears asymmetric, unilateral and well-demarcated. An irregular and partly, solid and cystic, or multiloculated mass is present. Calcifications are present in 50% of cases, and polyhydramnios appears in 20-40% of cases, and is caused by esophageal obstruction.

Ultrasound picture of a large cervical teratoma (yellow arrow). The red arrow points at the eyelids.

Picture of the neonate after delivery demonstrating the large tumor.

Prognosis: The prognosis is very grave. A 17% stillbirth rate has been reported[1], together with a mortality rate ranging between 80%  to 100%. Upper airway obstruction is the main cause of death. In infants treated surgically, the mortality rate reported ranges from 9%-17%[2]. It should be stressed that since these tumors tend to be large, extensive neck dissection and multiple additional procedures are necessary to achieve complete resection of the tumor with acceptable functional and cosmetic results.

References:

[1] Newstedt, J.R., Shirkey, H.C. Teratoma of the thyroid region. Am J Dis Child 1964; 107:88.

[2] Gundry, S.R., Weley, J.R., Klein, M.D. Cervical teratomas in the newborn. J Pediatr Surg 111983; 18:382-386.