Early-Onset Macrosomia, Advanced Brain Maturation, and Gonadoblastoid Testicular Dysplasia in a Fetus With a PTEN Variant.

We report a case of a male fetus with early-onset macrosomia and a pathogenic variant in PTEN identified on a macrocephaly and overgrowth sequencing panel. The pregnancy ended at 25 weeks gestation. On post-mortem examination, macrosomia was confirmed, and maturation of the brain was approximately 3 weeks ahead of that of the visceral organs. There was microscopic evidence of gonadoblastoid dysplasia, which is an extremely rare finding and has never been associated with PTEN hamartoma tumor syndrome (PHTS). To our knowledge, this is the first report of a prenatal phenotype with a heterozygous germline variant in PTEN.