Ultrasound and magnetic resonance imaging in prenatal diagnosis of sacrococcygeal teratoma--case report.

INTRODUCTION Fetal tumors are relatively rare and the early prenatal diagnosis enables the prediction of possible complications and decision for appropriate treatment. This paper deals with the role of ultrasonography and magnetic resonance imaging in the early prenatal diagnosis of sacrococcygeal teratoma. CASE REPORT A 21-year-old primigravida was found to have a large sacrococcygeal tumor measuring 25 x 30mm, presented mainly as a solid mass, when she underwent the initial ultrasound examination on the first day of 19th week of gestation. There were no other associated anomalies. The second ultrasound examination was obtained after 6 days and revealed that the tumor had doubled its size. The prominent enlargement raised suspicion of immature sacrococcygeal teratoma and thus, fetal magnetic resonance imaging was performed in the 20th gestation week. The examination showed a crococcygeal teratoma presented as a large solid mass with small microcystic areas, the largest diameter being 60mm, completely externally positioned with no intra-pelvic extension. Rapid tumor growth posed a threat to the fetal circulation and it was the main reason when opting for the termination of pregnancy at 20 weeks of gestation. Pathohystological examination confirmed the diagnosis of immature sacrococcygeal teratoma. DISCUSSION In the prenatal period the magnetic resonance imaging of a fetal tumor initially diagnosed by ultrasound examination is an additional part of diagnostic procedure, and it is not contraindicated during pregnancy. Magnetic resonance imaging improves the delineation of the tumor. The prompt prenatal diagnosis of sacrococcygeal teratoma, as well as the detection of possible associated anomalies, is important for the pregnancy management, prediction of possible complications and choice of appropriate treatment. CONCLUSION Ultrasonography and magnetic resonance imaging are noninvasive, compatible and complementary diagnostic modalities in evaluation of sacrococcygeal teratoma in prenatal period.