Interest and limits of endoscopic approaches for pineal region tumours

Results of the treatment of pineal tumors in children: the Lyon experience

INTRODUCTION

Pineal tumors are rare and their incidence is of 1% among all pediatric tumors of the central nervous system. Patient survival depends on the histology, the extension of the surgical removal, and the efficacy of the complementary treatment (chemotherapy and cranio-spinal irradiation), as well as the age of the patient.

MATERIALS AND METHODS

In this study, we analyzed 151 pediatric patients treated for pineal tumors from 1997 to 2020 in Lyon, France. All patients were recorded in the French Register of Pineal tumors, which has been centralized and maintained in Lyon since 2010.

RESULTS

Our analysis shows that benign tumors have an overall positive prognosis with total surgical removal. Concerning pineal parenchymal tumors, pinealoblastomas have a poor prognosis , especially in children less than three years old. A new pathological classification system allows for a better stratification of patient risk within different groups of patients with pineal tumors. It is also important to note that the identification of DICER 1 syndrome in families with pinealoblastomas warrant further medical investigation. Patients with Germ Cell Tumors have more favorable outcomes, with a global survival rate of 87 % and a pure germinoma survival rate of almost 97%. When analyzing the prognosis of pineal gland gliomas, otherwise known as tectal plate gliomas, pilocytic astrocytomas had a promising prognosis. Otherwise, prognosis of other tectal plate gliomas are related to the grade of malignancy and the efficacy of complementary treatment. Lastly, papillary tumors need a complete removal for the best chance of survival, and Atypical teratoid/ rabdoid tumors (AT/TR) still have a bad prognosis, regardless of surgical resection.

CONCLUSIONS

Our results show that, with regards to pediatric pineal region tumors, there are still areas in prognostic indicators that need to be improved. Similarly, these pathologies need to be treated via a multidisciplinary approach to improve a patient's survival rate and their quality of life.

Endoscope-Assisted Microsurgery in Pediatric Cases With Pineal Region Tumors: A Study of 18 Cases Series

Background: An endoscope-assisted technique was recently introduced to microsurgery (MS) and may compensate for the disadvantages of MS for deep-seated lesions. This study was performed to identify the effectiveness and safety of endoscopic-assisted microsurgery (EAM) and share our experience of EAM for pediatric cases with pineal region tumors.

Method: We retrospectively analyzed the clinical data of consecutive pediatric cases with pineal region tumors treated by EAM or MS from January 2016 to June 2020. These data included the patient population, clinical manifestations, preoperative examination findings, surgical approach, pathological results, and clinical outcomes. The clinical outcomes were analyzed in the EAM group and MS group with a focus on the gross total resection (GTR) rate, postoperative hydrocephalus remission rate, and Karnofsky performance score (KPS). Studies on the surgical management of children with pineal region tumors in the last decade were reviewed.

Result: Eighteen children successfully underwent tumor resection via MS (n = 8) or EAM (n = 10). The children's mean age was 11.4 ± 4.7 years, and the male to female ratio was 7:2. Seventeen patients (94.4%) complicated preoperative hydrocephalus, and 16 (88.9%) presented headache with nausea and/or vomiting. The pathological examination revealed germ cell tumors in 11 (61.1%) patients, neuroepithelial tumors in 4 (22.2%) patients, and a pineoblastoma, arachnoid cyst, and atypical teratoid rhabdoid tumor in 1 (5.6%) patient each. GTR was more commonly achieved in the EAM than MS group (80.0 vs. 50.0%, respectively), and the postoperative hydrocephalus remission rate was higher in the EAM than MS group (87.5 vs. 50.0%, respectively). At a mean follow-up time of 23.6 ± 11.5 weeks, the mean improvement of the KPS 6 months postoperatively was greater in the EAM than MS group (24.0 ± 9.7 vs. 17.5 ± 7.1 points, respectively).

Conclusion: EAM combines endoscopic and microsurgical techniques and can be safely and effectively performed to achieve GTR of pineal region tumors in pediatric patients. In children with pineal region tumors who have obstructive hydrocephalus, EAM could improves hydrocephalus remission rates by checking and clearing the midbrain aqueduct under visualization.

Endoscopic supracerebellar infratentorial approach to pineal and posterior third ventricle lesions in prone position with head extension: a technical note

OBJECTIVE

The supracerebellar infratentorial (SCIT) approach is frequently used for the treatment of lesions in the pineal and posterior third ventricle region and can be performed in a sitting or prone position. We describe our experience with the purely endoscopic SCIT approach, using a prone position, with neck extension and head rotation.

METHODS

We analysed all paediatric and adult patients operated on between July 2013 and January 2018 using the purely endoscopic SCIT approach. The surgical procedure was conducted through a paramedian subtorcular key-hole suboccipital craniotomy. The assistant held the endoscope and the surgeon used fine, long shaft instruments for bimanual tumour dissection. The prone position with head retroflexion allowed a gravity-aided enlargement of the anatomical surgical corridor between tentorium and cerebellum and enhanced venous blood drainage, similarly to the sitting or semi-sitting position, but with a decreased risk of air embolism.

RESULTS

The approach allowed a complete removal of lesions located in the pineal region and in the posterior part of the third ventricle. Seven patients have been operated with this approach. All of them had the tumour completely removed. No permanent neurological deficits have been observed.

CONCLUSIONS

The endoscopic SCIT approach enables effective and safe removal of pineal and posterior third ventricle lesions, even of moderate dimensions (up to 3 cm). The endoscope guarantees a detailed view and illumination of the deep-seated structures. The tumour resection can be performed with bimanual use of microsurgical instruments.

Endoscopic Ipsilateral Interhemispheric Approach for Resection of Selected Deep Medial Brain Tumors

BACKGROUND

The interhemispheric fissure provides a natural surgical corridor to access tumors of the deep medial surface of the brain. Conventional microscopic approaches to these tumors are limited by the narrow width of the interhemispheric fissure and need for retraction of brain tissue or traversing overlying cortex. Over the last decade, the endoscope has been used to improve visualization of the operative field in neurosurgery, with benefits in terms of surgical ergonomics and extent of tumor resections. In the context of the interhemispheric fissure, an endoscopic approach may improve visualization of some tumors by providing a brighter, more divergent light source at depth and by enabling the operator to inspect around curved structures (e.g., corpus callosum).

CASE DESCRIPTION

In this report, we present a series of 5 cases with tumors at various locations along the anteroposterior extent of the interhemispheric fissure that were resected using an endoscopic ipsilateral interhemispheric approach.

CONCLUSIONS

The endoscopic ipsilateral interhemispheric approach is an effective and versatile approach to resection of selected deep medial brain tumors extending anteriorly from the genu of the corpus callosum to the splenium. It has notable advantages over the microscope and can be considered a useful adjunct in the surgeon's armamentarium.

Pure Endoscopic Supracerebellar Infratentorial Approach to the Pineal Region: A Case Series

BACKGROUND

Surgical approaches to pineal lesions present a challenge because of limited visibility and maneuverability within the posterior fossa. The supracerebellar infratentorial (SCIT) technique has emerged as an approach to pineal lesions. We aim to demonstrate the efficacy of the endoscopic SCIT technique through a case series conducted at our institution and highlight the advantages of the endoscopic technique over the microscopic alternative.

OBJECTIVE

To evaluate the effectiveness and safety of the endoscopic SCIT approach.

METHODS

We conducted a retrospective review of pure endoscopic SCIT cases conducted at our institution. Demographic information, preoperative and postoperative imaging, neurological status, surgical data, and complications were recorded.

RESULTS

Six patients who underwent pure endoscopic SCIT surgery were identified for analysis. The average lesion volume was 14.12 ± 7.24 cm³. The median postoperative length of stay was 5.0 days. The average surgical duration was 3.54 ± 0.71 hours. All operations were performed in prone position with zero- and 30-degree endoscopes. Pathology included one each of the following lesions: Pineoctyoma, metastatic melanoma, atypical teratoma rhabdoid tumor, ependymoma, epidermoid, abscess. Gross total resection (GTR) was achieved in 5/6 patients, and near-total resection was achieved in 1/6 patients. Surgical complications included one case of postoperative infection.

CONCLUSION

The purely endoscopic SCIT approach is a safe and effective approach for deep-seated pineal lesions. This approach allows for visibility and maneuverability around the lesion and facilitates high rates of GTR.

[Purely endoscopic supracerebellar infratentorial approach for epidermoid cyst in third ventricle]

Introducción:

El Quiste Epidermoide como tumor de la región pineal es una patología infrecuente y poco descripta. Su prevalencia en el 3er ventrículo es de 0,0042% de los tumores primarios intracraneales. Para lograr la exeresis macroscópica total se utilizó el abordaje Supracerebeloso Infratentorial con Endoscopio rígido de Base de Cráneo, técnica descripta para abordaje de lesiones de la región pineal. El Objetivo del Trabajo es la presentación de la técnica quirúrgica del abordaje, con la resolución de la patología infrecuente que se presenta.

Materiales y métodos:

Paciente de 16 años de edad con antecedentes de DBT insípida y cefaleas crónicas intermitentes (m-RS 1). RMN de encéfalo evidencia lesión ocupante de espacio hiperintensa T2 e hipointensa en T1 con realce periférico y restricción en la difusión. Presenta refuerzo a nivel del tallo hipofisario. Se plantea diagnóstico de tumor germinal. Marcadores en LCR negativos. Se decide realizar abordaje puramente endoscópico de la región para toma de muestra. Congelación determina quiste epidermoide y se procede a realizar exeresis macroscópica total.

Resultados:

Se realizó exeresis macroscópica total de quiste de epidermoide en tercer ventrículo con abordaje supracerebeloso infratentorial a través de endoscópico rígido de base de cráneo, en paciente de 16 años, cursando postoperatorio tardío sin secuelas y mejoría sintomática con persistencia de DBT insípida (m-RS 1).

Conclusión:

El abordaje puramente endoscópico supracerebeloso infratentorial es una opción segura para el tratamiento quirúrgico de lesiones en el tercer ventrículo, en este caso, un quiste epidermoide.

The Purely Endoscopic Supracerebellar Infratentorial Approach for Resecting Pineal Region Tumors with Preservation of Cerebellomesencephalic Vein: Technical Note and Preliminary Clinical Outcomes

BACKGROUND

The cerebellomesencephalic vein (CMV) was frequently sacrificed in surgery approached via the supracerebellar infratentorial (SCIT) route for resecting pineal region tumors, which resulted in potential risk of neurologic deficit. Preserving the CMV in the SCIT approach could enhance the safety and effectiveness of this natural corridor surgery. The aim of this article was to identify the probability and safety of preserving the CMV through the application of neuroendoscopy in the SCIT approach.

METHODS

Clinical data of patients who underwent pineal region tumor resection through a purely endoscopic SCIT approach were retrospectively analyzed, focusing on surgical techniques and clinical outcomes.

RESULTS

The study included 8 patients with pineal region tumors. The CMV was preserved intact in all patients. Total tumor removal was achieved in 7 of 8 patients. In 1 patient with 2 tumors in the pineal region and roof of the third ventricle, the tumor in the pineal region was resected completely, followed by subsequent chemotherapy combined with radiotherapy, after which the other tumor disappeared totally. All patients recovered normally with uneventful postoperative outcomes.

CONCLUSIONS

The advantage of close observation and panoramic view provided by neuroendoscopy combined with meticulous manipulation improved the ability to preserve the CMV in resecting pineal region tumors via the SCIT approach. The neuroendoscopic technique enhances the safety and efficacy of the SCIT approach.