Prenatal Diagnosis of PIK3CA-Related Overgrowth Spectrum (PROS): A Case Report

Objective: Somatic mutations in PIK3CA cause segmental, progressive overgrowth of subcutaneous, muscular, skeletal and visceral tissue, encompassing a condition termed PIK3CA-Related Overgrowth Spectrum (PROS). PROS is thought to occur due to somatic mutation arising during embryonic development. Genetic testing of individuals is typically performed on affected tissue specimens; thus, diagnosis is often in childhood or adolescence. Literature regarding prenatal diagnosis for PROS is limited with two reports to our knowledge. We present prenatal findings and genetic analysis of a fetus with PROS adding to the published literature.