Sacrococcygeal Teratoma : A Tumor at the Center of Embryogenesis

Abstract

Sacrococcygeal teratoma (SCT) is an extragonadal germ cell tumor (GCT) that develops in the fetal and neonatal periods. SCT is a type I GCT in which only teratoma and yolk sac tumors arise from extragonadal sites. SCT is the most common type I GCT and is believed to originate through epigenetic reprogramming of early primordial germ cells migrating from the yolk sac to the gonadal ridges. Fetal SCT diagnosed in utero presents many obstetrical problems. For high-risk fetuses, fetal interventions (devascularization and debulking) are under development. Most patients with SCT are operated on after birth. Complete surgical resection is the key for tumor control, and the anatomical location of the tumor determines the surgical approaches. Incomplete resection and malignant histology are risk factors for recurrence. Approximately 10-15% of patients have a tumor recurrence, which is frequently of malignant histology. Long-term surveillance with monitoring of serum alpha fetoprotein and magnetic resonance imaging is required. Survivors of SCT may suffer anorectal, urological, and sexual sequelae later in their life, and comprehensive evaluation and care are required.

Keywords: Fetus; Germ cell tumor; Surgery; Teratoma, Sacrococcygeal.

Fig. 1.

Sacrococcygeal teratoma of a female newborn. A : In utero ultrasonography taken at gestational age of 35+3 week reveals a multi-cystic mass protruding outward from the sacrococcygeal area; (B) coronal and (C) sagittal T1-weighted magnetic resonance images show a huge multi-cystic heterogeneous mass located in both intrapelvic and extracorporeal spaces; (D) a gross photograph of the tumor resected at 6th postnatal day.

Fig. 2.

Altman classification of sacrococcygeal teratoma according to the anatomical configuration. A : Type I : predominantly external with small internal components. B : Type II : dumbbell-shaped tumor with similar internal and external components. C : Type III : predominantly internal and smaller external components. D : Type IV : exclusively internal (intrapelvic) tumor.