Two case reports of rare fetal tumors: an indication for surface rendering?

Fetal tumors are rare and can be difficult to diagnose in utero. This report describes one case of an extrarenal rhabdoid tumor and one case of a giant congenital melanocytic nevus. Both presented with moderate polyhydramnios and were prenatally detected at 31 weeks of gestation with two-dimensional ultrasound. The application of the surface mode of three-dimensional ultrasound improved the visualization of these tumors especially for the parents and the multidisciplinary team. Three-dimensional sonography proved to be a valuable addition to the prenatal armamentarium for the evaluation of these fetal tumors although it is not mandatory for their assessment and clinical management.