Gynecology and Oncology Fetal Myofibromatosis: A Challenge for Prenatal Diagnosis Mini Review of the English Literature

Importance: Infantile myofibromatosis (IM) is a benign neoplasm with a reported incidence of 1:150,000. The "solitary" type is characterized by a single lesion in the skin, muscle, or bone, whereas the "multicentric" type may also involve the viscera. Objective: This report describes the prenatal diagnosis of IM and recommendations for future pregnancy follow-up. Evidence Acquisition: This systematic search of the English literature yielded 8 reports documenting prenatal diagnosis of IM between 1999 and 2018. Results: Fetal age at diagnosis ranged from 13 to 38 weeks of gestation. Seven cases were diagnosed in the third trimester (30-34 weeks). Five cases were of the "solitary" type, and all successfully underwent surgical removal of the tumor with a good outcome. Three were of the "multicentric" type, and the 1 infant presenting with diffuse disease died several weeks after delivery. Conclusion and Relevance: The prenatal diagnosis of IM is often not made until the third trimester following a normal second-trimester anomaly scan, likely due to development of this lesion over time. Women should be referred for genetic counseling and consideration of preimplantation genetic diagnosis following the delivery of an affected child with the autosomal recessive form of the disorder and identified causative pathogenic variants.