Prognostic role of tumor-head volume ratio in fetal sacrococcygeal teratoma

Objective: To evaluate the ability of a tumor-head volume ratio to predict outcome and incidence of hydrops in fetuses with sacrococcygeal teratoma. Methods: Seventy-one sonograms were reviewed retrospectively from 28 fetuses with sacrococcygeal teratoma managed in our institution. Head volume (HV) and total tumor volume were calculated from sonograms. Amount of cystic tumor was estimated to determine solid tumor volume (STV) for the STV/HV ratio. Results: Twenty percent of sonograms with STV/HV <1 and 97.3% with STV/HV >1 were associated with 1 or more abnormal sonographic signs (p = 0.000). Overall mortality was 11/27 (41%). There was no mortality in fetuses with a ratio of <1, while 11/18 (61%) of fetuses with ratio >1 died (p = 0.003). Conclusion: The STV/HV ratio may be used to identify fetuses with a high risk of a poor outcome due to high-output cardiac failure and hydrops, and may help guide management.