Prognostic Value of Antenatal Tumor Growth Rate Parameters in Fetal Sacrococcygeal Teratoma: A French Multicenter Retrospective Study

ABSTRACT Objectives Although rare, sacrococcygeal teratoma is the most common type of fetal tumor. It requires close antenatal monitoring to anticipate complications. We sought to determine whether the tumor growth rate was predictive of complications. The objective was to investigate the association between the growth rate of tumor volume, tumor diameter and the ratio of tumor volume to head circumference and extended perinatal morbidity and mortality. Secondly, we proposed a growth threshold predictive of poor outcome. Methods We conducted a retrospective multicenter observational study of ultrasound data from fetuses with an antenatal diagnosis of sacrococcygeal teratoma between 2011 and 2021 in France. Results Among the 28 cases, fetuses that died or required transfusion/vasopressors at birth presented with a higher growth rate for all three parameters. After adjusting by multivariate analysis, only a higher tumor volume growth rate ( p  = 0.043) was significantly associated with extended perinatal morbidity and mortality. A tumor volume growth rate > 18.01 cm 3 /week and a volume > 245 cm 3 at any stage of pregnancy were associated with a poor perinatal outcome. Conclusions The volume growth rate is associated with extended perinatal morbidity and mortality. Tumor volume, per se, seems to play an important role in this association.