Association of gestational choriocarcinoma in a mother and Li-Fraumeni syndrome in her child: The result of a single event?

Abstract

Li-Fraumeni Syndrome (LFS) is a cancer predisposition syndrome caused by germline TP53 mutations. LFS is typically inherited but can also arise de novo. In children with LFS, the most common malignancies are adrenocortical carcinomas, brain tumors, and soft tissue sarcomas. Herein, we present a 5.5-year-old girl with a novel TP53 germline mutation (NM_000546.4, c.132_147dup; p.Ile50Alafs*7) associated with an unusual and aggressive oncologic phenotype in the context of LFS. Over five years, the patient successively developed undifferentiated sarcoma, Burkitt lymphoma and extra-skeletal osteosarcoma. There was no family history of LFS, but the proband's mother had died shortly after her pregnancy from a gestational choriocarcinoma caused by the same TP53 mutation as the proband. We present the first case of a TP53 mutation from non-carrier parents affecting both mother and child to date. We describe the pathogenic variant and the possible mechanism underlying the co-occurrence of the proband's LFS and her mother's gestational choriocarcinoma.