Molecular genetics of gliomatosis peritonei emerging after complete resection of immature ovarian teratoma

Abstract

Gliomatosis peritonei (GP) is characterized by peritoneal dissemination of glial tissue and is almost exclusively associated with ovarian immature teratoma (OIT). However, little is known about their clonal origins. Here, we performed whole-exome sequencing (WES) to investigate the clonal relationship between GP and OIT in a 14-year-old girl diagnosed with a surgically resected left OIT. Thirteen months postoperatively, multiple peritoneal disseminated lesions were detected. Histological analysis confirmed the diagnosis of GP. Copy number analysis revealed a copy-neutral loss of heterozygosity affecting all chromosomes, with a common pattern in both tissues. Somatic mutation analysis revealed that mutations detected in each tissue were acquired independently. No driver mutations involved in tumorigenesis or tumor progression were identified. These findings suggest that GP originated from a common ancestral clone with OIT. Further investigation is necessary for the factors determining the phenotypic differences between OIT and GP.