Recent Comprehensive Article on SCTs
I thought the group might be interested in the recent publication
of a comprehensive retrospective analysis of 30 cases of fetal SCTs.
The article is entitled "Sacrococcygeal Teratoma: Prenatal Assessment,
Fetal Intervention, and Outcome" (Hedrick et al. 39 J. of Ped.
Surg. pp. 430-438 March 2004). The paper was authored by a group
of pediatric surgeons and Ob/Gyns working out of Childrens Hospital
of Philadelphia (CHOP). It analyzes the authors' experiences with
all 30 cases of fetal SCTs that presented at CHOP between September
1995 and January 2003. This study represents the largest series of
fetal SCTs studied to date. A summary of the article follows.
Enrollment and Associated Anomalies
During the seven year study period, thirty women presented with an average maternal
age of 29 years (range, 18 to 40). The mean gestational age at the time of CHOP
evaluation was 23.9 weeks (range, 19 to 38.5). Tumor composition on prenatal
ultrasound scan consisted of 19 solid, 5 cystic, and 6 mixed solid/cystic tumors.
The most common associated anomaly diagnosed by ultrasound or MRI was urinary
obstruction (13/30 or 43%). Musculoskeletal problems included hip dislocation
(n=2) and club feet (n=2). Severe pulmonary hypoplasia was found in 3 fetuses
secondary to complications of inadequate amniotic fluid.
5 Fetal Deaths
7 Neonatal Deaths
Intrauterine fetal death occurred in 5 fetuses at a mean gestational age of 26.6
weeks (range, 24.6 to 28.7). In 3 of the 5 fetal deaths, high-output cardiac
failure and hydrops were present before death. In the remaining 2 fetal death
cases, Doppler studies revealed decreasing end-diastolic flow volumes and reversal
of diastolic flow. Altman tumor types were as follows: Type I (n=1), Type II
(n=2), and Type III (n=2). All tumors in the fetal death group were solid.
Seven neonatal deaths occurred at a mean gestational age of 28.6 weeks (range,
25.3 to 32.3). Five of the seven tumors in this group ruptured and bled either
in utero during preterm labor or during surgery. Altman tumor types for this
group were as follows: Type I (n=4), Type II (n=2), Type III (n=1). Six of the
tumors in this group were solid and one was mixed solid/cystic.
Standard Postnatal Care
11 of the 14 survivors underwent standard postnatal tumor resection (the paper
does not discuss what happened with the remaining 3 survivors). Altman tumor
types for this group were: Type I (n=5) and Type II (n=6). The composition of
the tumors was cystic (n=5), mixed solid/cystic (n=5) and solid (n=1). In the
9 patients treated at CHOP, the mean gestational age at birth was 36 weeks (range,
33 to 39). All survivors were delivered by c-section. All survivors underwent
SCT removal surgery on day 1 or day 2 of life. Two patients had tumor recurrences
detected after AFP levels increased at 5 and 16 months of age. Both children
underwent reresection. The 16 month old patient underwent a course of chemotherapy.
Both patients are now alive and well with no evidence of the disease. Mean hospital
stay was 19 days (range, 6 to 37).
Selection for Fetal Intervention
There were 14 instances of fetal intervention among the 30 subjects. Fetal intervention
was defined as amnioreduction (n=3), amnioinfusion (n=1), cyst aspiration (n=6),
and open fetal surgery (n=4). The fetus who received amnioinfusion (due to inadequate
amniotic fluid) did not survive. This fetus received amnioinfusion at weeks 29,
31 and 32 in an (ultimately unsuccessful) effort to facilitate lung growth. The
only other non-surviving fetus in this group was a baby who died from complications
arising out of a prior open fetal surgery procedure. The goal of prenatal amnioreduction
and cyst aspiration was maternal comfort and reduction of uterine irritability.
In 3 cases, cyst aspiration was performed just before delivery to preclude birth
trauma. Criteria for consideration of open fetal surgery for debulking of the
tumor mass include the following: no maternal risk factors for anesthesia or
surgery, a single fetus with normal chromosome pattern, absence of significant
associated anomalies, affirmative evidence of impending high-output cardiac failure,
gestational age < 30 weeks, and favorable tumor anatomy (Altman Type I or
Significant obstetrical complications occurred in 81% of the 26 continuing pregnancies
as follows: excessive amniotic fluid (n=7), inadequate amniotic fluid (n=4),
preterm labor (n=13), preeclampsia (n=4), gestational diabetes (n=1), HEELP syndrome
(n=1), and hyperemesis (n=1).
The authors clearly view RFA as still very experimental. They reference a report
on 4 patients treated with RFA. 2 of the 4 patients died secondary to blood loss
after a large portion of the tumor mass was ablated. The remaining 2 patients
were delivered at 28 and 31 weeks gestation with evidence of perineal and gluteal
dead tissue requiring additional surgeries. A second report on use of RFA described
intrauterine fetal death on postoperative day 2. A third report on use of RFA
described a newborn in whom RFA resulted in a large soft tissue defect, hypoplastic
hip joint, and loss of sciatic nerve function. The authors conclude their discussion
on RFA by stating that it may be promising but that there needs to be additional
testing of the physical and thermal effects of the ablation techniques in normal
fetal animal models before further clinical application.
While reviewing this study, I was struck by how little experience even our leading
medical institutions have with fetal SCTs. In a seven year period, only 30 cases
of fetal SCT were presented at a leading institution such as CHOP. In other words,
CHOP sees less than 5 fetal SCTs in any given year. The other leading institution
for the treatment of SCTs, Univ. of Cal. at San Francisco, only saw a total of
17 SCT fetuses over a 12 year period from 1986 to 1998. The figure of 1 in 40,000
live births as an incidence of SCTs would yield approximately 300 babies born
with an SCT annually in the United States alone. The low numbers seen by CHOP
and UCSF suggest that many neonates with SCT's were not diagnosed with the condition
in utero. If the SCT develops later in the pregnancy or grows very slowly, it
is entirely possible that it would not be picked up on the 1 or 2 ultrasounds
a normal pregnancy typically yields. It would seem that the group of prenatally
diagnosed SCT babies is a small subset of an already small group of babies born
with an SCT.
The second thing I was struck by when reading the paper was the complete absence
of any discussion of the relative condition of the 4 babies whose parents elected
to abort. It would have been instructive to see whether there was any correlation,
for example, between the voluntary termination of the pregnancy and the degree
of issues presented by the SCT in each case. My gut tells me that there is no
correlation between the relative seriousness of the appearance of the tumor and
the decision to abort. Based on my own experience and the shared experiences
of others, I believe that medical professionals are frequently guilty of subtle
steering of a parent's decision towards termination of the SCT pregnancy (even
in the context of "non-directed" counseling). When a physician chooses
to identify only the risks and threats and ignores or fails to discuss the positive
signs present (e.g. external presentation, cystic composition, non-vascularity)
the physician is effectively steering certain parents towards termination in
a manner that does not even produce informed consent to the termination procedure.