Prenatal ultrasound diagnosis of infantile myofibromatosis--a case report.

Infantile myofibromatosis, the most common soft tissue tumor of infancy, was diagnosed at 30 weeks of gestation. The tumor presented on ultrasound as a large mass measuring 42 mm x 75 mm x 35 mm located on the fetal back. The ultrasound diagnosis was further validated by MRI. Termination of pregnancy was carried out, and a multicentric visceral type of the tumor was diagnosed at autopsy.