Predictors of poor prognosis in prenatally diagnosed sacrococcygeal teratoma: A multiinstitutional review.

INTRODUCTION: Attempts at defining predictors of poor outcome in fetal sacrococcygeal teratoma (SCT) have been hampered by small patient numbers. We sought to validate the utility of tumor volume to fetal weight ratio (TFR) as a predictor of poor prognosis and to identify other morphological outcome predictors in a multicenter series.

METHODS: Records of prenatally diagnosed SCT at three fetal centers from 1986 to 2011 were reviewed. Prenatal imaging characteristics including TFR, morphology, hydrops, and placentomegaly were assessed. Poor prognosis was defined as fetal demise, need for fetal intervention, or perinatal death. Receiver operating characteristic (ROC) analysis was used to select a TFR cutoff value.

RESULTS: Seventy-nine fetuses with SCT were evaluated. Eleven pregnancies ending in elective termination were excluded. ROC analysis revealed that TFR >0.12 prior to 24 weeks gestation was predictive of poor prognosis (AUC=0.913; Sensitivity=91.7%, Specificity=76.2%, PPV=86.8%; NPV=84.2%). Solid tumor morphology and presence of hydrops were found to be predictors of poor prognosis. None of the factors associated with poor prognosis were independent predictors on multivariate analysis.

CONCLUSION: This study validates TFR >0.12 prior to 24 weeks gestation as an objective predictor of outcomes in fetuses with SCT that can be easily applied in most clinical settings.