2000-05-09-11 Sacrococcygeal teratoma © Kivilevich www.thefetus.net/
Sacrococcygeal teratoma
Beer Sheva, Israel
Definition: A tumor originating from a multipotential embryonic cells, situated in the so called Hensen"s node ( Primitive knot), a part of the primitive streak.
Pathology: Mature and immature teratomas represent 87% to 93% of all cases. Malignant tumors represent other 7 % to 13%[1]. The neurologic tissue represents a major constituent.
Classification
TYPE 1 : Predominantly external, with minimal presacral componrent.
TYPE 2 : Predominantly external, with significant intrapelvic component .
TYPE 3 : Predominantly internal, with abdominal extension.
TYPE 4 : Entirely internal with no external component .
Type 1 and 2 include 80 % of the cases[2]. Only 10% of the SCT are of type 4[3]. Of this group, only 15% are entirely cystic. The presence of functioning choroid plexus, is thought to be responsible for the cystic component[4].
Incidence: 0.02-0.03:10,000 live births[5]. Approximately 80% are female (M4:F1)[6],[7].
Recurrence: The majority are sporadic. 26 cases of familial hereditary pattern were reported until 1989[8],[9]. The familial type of SCT has different characteristics with:
- Female to male ratio of 1:1
- It was entirely presacral in all cases.
- It was associated with anal stenosis and sacral defect together, and
- It was usually benign.
Differential diagnosis of presacral cystic masses
1) Anterior meningocele ( ASM) . It rarely coexist with SCT in the same fetus. Only 6 such cases reported in the literature until 1989. Currarino syndrome (a triad consisting of anorectal malformations, sacral bony defect, and presacral mass, benign teratomas) It represents 18 % of the presacral masses[10].
2) Neuroectodermal cyst[11]
3) Perineuronal cyst (Tarlov"s cyst)[12]
4) Gastrointestinal:
a. Rectal obstruction / dilatation.
b. Bowel duplication.
c. Meconium pseudocyst.
5) Retroperitoneal tumor of mesenchymal origin
6) Ovarian cyst
7) Pelvic kidney cyst
Associated anomalies: Reported incidence in postnatal studies: 5 % to 25% . Involving various systems with no specific pattern[13]. Prenatal series , in contrast , did not report any case of associated malformations including aneuploidies (Ref. 15- 30 , Tab 1.)
Table 1
Sacrococcygeal Teratoma : Outcome – Prenatal series
Author | Number Cases | Terminatiuon of pregnancy | Associated Malformations ** | Chrom. Abnorm. | Perinatal mortility | Live & well | Late infant death |
Gross S.J et.al 1987 | 10 | 1 | / | / | 1 | 8 | 1* |
Hogge W.A et. al. 1987 | 2 | / | / | / | / | 2 | / |
Sheth S. et.al. 1988 | 15 | 2 | / | / | 7 | 6 | / |
Teal L. M et.al 1988 | 3 | / | / | / | 1 | 2 | / |
Bond S.T et.al 1990 | 48 # | 11 | / | / | 17 | 20 | / |
Evans M.J et.al. 1994 | 1 | 1 | / | / | / | / | / |
Shipp T.D et.al. 1996 | 1 | / | / | / | / | 1 | / |
Winderl L.M and Silverman R.K 1997 | 1 | / | / | / | / | 1 | / |
Sherer D.M et.al 1997 | 1 | / | / | / | / | 1 | / |
Kirkinen P. et. al. 1997 | 10 | / | / | / | 1 | 9 | / |
Montgomery M.L et.al 1998 | 1 | / | / | / | / | 1 | / |
Burgess I. et . al. 1998 | 1 | / | / | / | / | 1 | / |
Holterman A.X et .al. 1998 | 21 | / | | | 7 = 33% | 14 | |
Chisholm CA et .al. 1999 | 9 | / | / | / | 3 | 6 | / |
Brace V. et. al. 2000 | 10 | 2 | / | / | 5 | 3 | / |
TOTAL | |