Summary of Medical Study
Article Title: "Sonographic Prognostic Factors in Fetuses
with Sacrococcygeal Teratoma (Westerburg et al, 35 J. of Ped. Surg.
pp. 322-326 Feb. 2000)"
The aim of this study by a group working out of Univ. of Cal. at San Francisco
was to attempt to identify sonographic factors associated with the development
of fetal hydrops and an unfavorable pregnancy outcome. The authors reviewed the
histories of 17 fetal SCT cases presented at UCSF from 1986 to 1998.
There were no significant differences in tumor size or ratio of tumor size to
fetal head or abdomen circumference between fetuses that had hydrops (n=12) and
those that did not have hydrops (n=5). The group of hydropic fetuses, however,
differed significantly in the following three (3) categories: tumor vascularity;
tumor morphology (shape); and presence of intrapelvic extension of the tumor.
Fetuses with hydrops had tumors that were vascular, solid, and extended into
the pelvic region. Non-hydropic fetuses, however, had tumors that were predominantly
cystic, minimally vascular, and largely external.
Of the 12 hydropic fetuses, only 4 survived. 3 of the 4 developed hydrops prior
to viability and underwent open fetal surgical intervention. The fourth surviving
hydropic fetus developed hydrops at 32 weeks and was immediately delivered by
The most common obstetric indication for sonography in this setting is fundal
height greater than expected for the gestational age. The abnormal fundal height
is caused by tumor mass or associated polyhydramnios (excessive amniotic fluid).
The size of the tumor is not a predictor of outcome in the case of fetal SCTs.
More important than tumor size in predicting outcome is the relative vascularity
of the tumor along with the degree of intrapelvic extension. Basically, the more
vascular the tumor and the greater the degree of an internal component, the worse