Surgical management of diffuse brainstem high-grade gliomas

https://doi.org/10.59156/revista.v37i03.547

Abstract

Background: Brainstem diffuse tumors represent approximately 10% of pediatric CNS tumors. Among them, H3K27M-mutant diffuse midline gliomas (DMGs) are rare childhood central nervous system tumors that carry a dismal prognosis, with a mean survival time of 9-15 months.

Tumor biopsy is not only helpful for addressing a correct diagnosis, but is also an important strategy for the continuous study of further therapeutic options, given the former known bad prognosis with standard treatment.

Objective: Our objective is to communicate, through the presentation of two clinical cases, our experience with these tumors by performing a biopsy through a subtemporal approach.

Cases description: Two patients underwent tumor biopsy through a subtemporal approach at our institution in 2022. Both patients presented with MRIs compatible with diffuse pons gliomas. These cases were retrospectively reviewed and the surgical approach described.

We also review and compare the different surgical approaches as well as treatment options for this pathology.

Surgery: The patients presented no postoperative complication. Both patient’s biopsy results were H3K27M-mutant diffuse midline gliomas and underwent oncological treatment and follow up.

Although stereotactic biopsy is the most commonly used practice, at our institution we choose to use open surgery through a subtemporal approach. It has proven to provide a better surgical view with a chance of greater biopsy samples, satisfactory bleeding control with no added comorbidities.

Nowadays, biopsy has proven fundamental for the treatment and follow up of these patients.

Conclusion: DMGs are rare childhood central nervous system tumors that carry a dismal prognosis. Historically, biopsy for brainstem diffuse tumors was used only when the diagnosis was not clear. Nowadays, with the forthcoming of different surgical techniques and the development of new subtypes of molecular targets, the biopsy seems a fundamental step. The subtemporal approach is an excellent alternative to biopsy this pathology.