Teratomas of the cranial vault: a systematic analysis of clinical outcomes stratified by histopathological subtypes

Genomic characterization of intracranial teratomas using whole genome sequencing

Background

Intracranial teratoma is a rare neoplasm of the central nervous system, often classified into mature and immature types and occurs mainly in children and adolescents. To date, there has been no comprehensive genomic characterization analysis of teratoma due to its rarity of the cases.

Methods

Forty-six patients with intracranial teratomas were collected and 22 of them underwent whole-exome sequencing, including 8 mature teratomas and 14 immature teratomas. A comprehensive analysis was performed to analyze somatic mutations, copy number variants (CNVs), mutational signatures, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway in our cohort.

Results

The most common somatic mutated gene in intracranial teratomas was CARD11 (18%) and IRS1 (18%), followed by PSMD11, RELN, RRAS2, SMC1A, SYNE1 and ZFHX3, with mutation rates of 14% for the latter six genes. Copy number variation was dominated by amplification, among which ARAF (50%), ATP2B3 (41%), GATA1 (41%), ATP6AP1 (36%), CCND2 (36%) and ZMYM3 (36%) were the most frequently amplified genes. Copy number deletion of SETDB2 and IL2 only appeared in immature teratoma (43% and 36%, respectively), but not in mature teratoma (p = 0.051 and 0.115, respectively). Prognostic analysis showed that TP53 mutations might be associated with poor prognosis of intracranial teratomas patients.

Conclusions

Our study revealed the genetic characteristics of intracranial teratoma which might be valuable for guiding future targeted therapies.

Pure germinoma occurring 11 years after total pineal mature teratoma removal: a case report and review of the literature

Intracranial mature teratomas have good prognoses and are usually treated by total tumor resection. We report a rare case of a germinoma that occurred 11 years after total removal of a pineal mature teratoma. A 5-year-old boy presented with headache and nausea and was diagnosed with a pineal tumor and obstructive hydrocephalus on MRI. He underwent total removal of the lesion, which was pathologically diagnosed as a mature teratoma without any other germ cell tumor components. MR images after 11 years showed a newly developed pineal tumor, which was confirmed as a germinoma after neuroendoscopic biopsy. Chemoradiotherapy resulted in complete remission, without any symptoms. This case demonstrated possible late occurrence of germinoma even after total removal of a mature teratoma had been achieved. A long-term follow-up of 10 years or more should be planned for these patients.