Fully endoscopic occipital transtentorial approach for pineal region tumors.

PURPOSE: Aggressive surgical resection for pineal region tumors, which is a mainstay of management in almost all cases, remains technically challenging because these tumors are located at the geometric center of the brain and surrounded by critical neurovascular structures. Therefore, any refinement in the surgical procedure is desirable. We have recently introduced an endoscope to the occipital transtentorial approach (OTA), which has been one of the most common procedures for reaching the pineal region, to overcome some of the disadvantages of the procedure, including the necessity of a relatively large skin incision and bone opening, the difficulty in orientation due to the obliqueness of the approach, the possibility of retraction injury on the occipital lobe and the corpus callosum, and blind spots at the ipsilateral wall and the roof of the third ventricle. METHODS: We performed endoscopic OTA with corresponding advantages, including less invasiveness by virtue of a small entrance limiting the retraction of the occipital lobe, the elimination of blind spots, and the facilitation of fine manipulation based on the bright endoscopic view even at substantial depth, which is panoramic and can be magnified as needed. This procedure was substantially different from a conventional microscopic OTA, though both use a similar corridor. To maximize maneuverability within the limited space in endoscopic OTA, it was necessary to thoroughly understand each step of the procedure, as well as optimal sequence in the procedure. RESULTS AND CONCLUSION: We found endoscopic OTA to be a promising technique for resectioning pineal region tumors, with the potential for extensive and routine application for surgeons familiar with endoscopic surgery.

Pineal/germ cell tumors and pineal parenchymal tumors.

INTRODUCTION: Pineal region tumors (PRTs) are tumors arising from the pineal gland and the paraspinal structures. These tumors are rare and heterogeneous that account for 2.8-10.1% and 0.6-3.2% of tumors in children and in all ages, respectively. Almost all types and subtypes of CNS tumors may be diagnosed in this region. These tumors come from cells of the pineal gland (pinealocytes and neuroglial cells), ectopic primordial germ cells (PGC), and cells from adjacent structures. Hence, PRTs are consisted of pineal parenchyma tumors (PPTs), germ cell tumors (GCTs), neuroepithelial tumors (NETs), other miscellaneous types of tumors, cystic tumors (epidermoid, dermoid), and pineal cyst in addition. The symptoms of PRTs correlate to the increased intracranial cranial pressure due to obstructive hydrocephalus and dorsal midbrain compression. The diagnostic imaging studies are mainly MRI of brain (with and without gadolinium) along with a sagittal view of whole spine. Serum and/or CSF AFP/ß-HCG helps to identify GCTs. The treatment of PRTs is consisted of the selection of surgical biopsy/resection, handling of hydrocephalus, neoadjuvant and/or adjuvant therapy according to age, tumor location, histopathological/molecular classification, grading of tumors, staging, and threshold value of markers (for GCTs) in addition. METHODS: In this article, we review the following focus points: 1. Background of pineal region tumors. 2. Pineal GCTs and evolution of management. 3. Molecular study for GCTs and pineal parenchymal tumors. 4. Review of surgical approaches to the pineal region. 5. Contribution of endoscopy. 6. Adjuvant therapy (chemotherapy, radiotherapy, and combination). 7. RESULTS: In all ages, the leading three types of PRTs in western countries were PPTs (22.7-34.8%), GCTs (27.3-34.4%), and NETs (17.2-28%). In children and young adults, the leading PRTs were invariably in the order of GCTs (40-80.5%), PPTs (7.6-21.6%), NETs (2.4-37.5%). Surgical biopsy/resection of PRTs is important for precision diagnosis and therapy. Safe resection with acceptable low mortality and morbidity was achieved after 1970s because of the advancement of surgical approaches, CSF shunt and valve system, microscopic and endoscopic surgery. Following histopathological diagnosis and classification of types and subtypes of PRTs, in PPTs, through molecular profiling, four molecular groups of pineoblastoma (PB) and their oncogenic driver were identified. Hence, molecular stratified precision therapy can be achieved. CONCLUSION: Modern endoscopic and microsurgical approaches help to achieve precise histopathological diagnosis and molecular classification of different types and subtypes of pineal region tumors for risk-stratified optimal, effective, and protective therapy. In the future, molecular analysis of biospecimen (CSF and blood) along with AI radiomics on tumor imaging integrating clinical and bioinformation may help for personalized and risk-stratified management of patients with pineal region tumors.

Pediatric pineal region masses: a single-center experience over 25 years.

PURPOSE: Pineal region tumors (PRT) represent less than 1% of brain neoplasms. The rare and heterogeneous nature of these tumors is reflected in the variety of treatment modalities employed. METHODS: A single-center retrospective review of all pediatric patients with pineal region tumors between November 1996 and June 2021 was performed. Fifty-six cases of pineal tumors were reviewed for age and symptoms upon presentation, diagnostic methods, imaging characteristics, histological classification, treatment modalities, recurrence, and mortality rates. RESULTS: The average age at diagnosis was 11.3 years. The majority of patients were male (82.1%) and Caucasian (73.2%). The most common presenting symptoms were headache (n = 38, 67.9%) and visual problems (n = 34, 60.7%). Hydrocephalus was present in 49 patients (87.5%). Germinoma (n = 20, 35.7%) and non-germinomatous germ cell tumor (NGGCT) (n = 17, 30.4%) were the most common tumors. Chemotherapy was employed for 54 patients (96.4%), radiation for 49 (87.5%), and surgical resection for 14 (25.0%). The average duration of treatment was 5.9 months. Progression-free survival was 74.4% at 5 years and 72.0% at 10 years. Overall survival was 85.7% at 5 years and 77.1% at 10 years. CONCLUSION: Treatment of pineal region tumors must be targeted to each patient based on presentation, subtype, presence of hydrocephalus, and extent of disease. Upfront surgical resection is usually not indicated. As advances in oncological care proceed, treatment modalities may continue to improve in efficacy.

Transcallosal-lateral ventricle-choroid fissure approach for excising large pineal region tumors extending into the third ventricle: experience in 15 pediatric cases.

Pineal region is deep located and tightly connected with surrounding important nerves, blood vessels, and other critical structure. Tumors in the regions are more commonly observed in children with complex pathology, difficult surgery, and poor prognosis. However, excision surgery on large tumor in the pineal region and extending into the third ventricle is characterized by high difficulty and uneasy treatment. Related experience and knowledge about excising large tumor in children pineal region which extending into the third ventricle by transcallosal-lateral ventricle-choroid fissure approach was described in the paper. Clinical data of 15 children patients with large tumors in pineal region which extending into the third ventricle treated by our group from 2011 to 2015 was retrospectively analyzed (< 15 years of age, tumor size > >3 × 3 × 3 cm3). Fifteen cases underwent tumor excision with surgery by transcallosal-lateral ventricle-choroid fissure approach including 11 male patients and 4 female patients with average age of 9.1 years and tumor volume from 3 × 3 × 3 to 5 × 6 × 7 cm3. They were assessed according to postoperative clinical symptom remission rate, blood loss during surgery, tumor removal rate, postoperative recurrence rate, etc. as indicators. Five cases belonged to germ cell tumors, 4 for teratoma, 1 for malignant teratoma, 2 for glioma, 2 for meningioma, and 1 for pineocytoma. Surgical total excision rate was 100%, while the mean intraoperative blood loss was about 300 ml. No case was dead due to surgery, and all cases had good postoperative recovery. Children patients are characterized by less blood than adults, larger volume size during surgery treatment, poor postoperative anti-infectious ability, etc. High requirements are proposed on surgery treatment, by long-term clinical exploration and experience accumulation. Our group believes that surrounding structures such as veins and dome are stretched and stimulated rarely in excision of children in large and medium tumor in pineal region which extending into the third ventricle by transcallosal-lateral ventricle-choroid fissure approach; thereby, the tumor can be completely excised, and larger veins and other important structures can be well-preserved with fewer complications, high full cut rate, and rapid recovery.

Endoscopic-assisted surgery versus microsurgery for pineal region tumors: a single-center retrospective study.

Pineal region tumors are extremely deep-seated and surgically challenging. The exposure and visualization obtained by microscopic surgery are relatively limiting. The application of high-definition endoscopes has recently provided neurosurgeons with a much more magnified and clearer view of the anatomy in the pineal region. The present study was performed to compare endoscopic-assisted surgery (ES) with microsurgery (MS) for pineal region tumors. We retrospectively analyzed patients admitted to our hospital for treatment of pineal region tumors from January 2016 to June 2019. All patients consented to undergo tumor resection with ES or MS. We compared the extent of resection, postoperative rate of hydrocephalus, complications, and outcomes between the two groups to estimate the safety and efficacy of ES. In total, 41 patients with pineal region tumors were divided into 2 groups: the ES group (n = 20) and MS group (n = 21). The rate of gross total resection was significantly higher in the ES than MS group (90.0% vs. 57.1%, p = 0.04). The rate of postoperative hydrocephalus was significantly lower in the ES than MS group (11.8% vs. 52.9%, p = 0.03). No significant differences were found in complications or the Karnofsky Performance Score between the two groups. ES can be used to safely and effectively achieve complete resection of pineal region tumors. In patients with obstructive hydrocephalus, ES provides a new way to directly open the aqueduct for cerebrospinal fluid recovery following tumor resection.

Management of pineal region tumors in a pediatric case series.

Pineal region tumors commonly present with non-communicating hydrocephalus. These heterogeneous histological entities require different therapeutic regimens. We evaluated our surgical experience concerning procurance of a histological diagnosis, management of hydrocephalus, and choice of antitumoral treatment. We analyzed the efficacy of neuroendoscopic biopsy and endoscopic third ventriculocisternostomy (ETV) in patients with pineal region tumors between 2006 and 2019 in a single-center retrospective cross-sectional study with regard to diagnostic yield, hydrocephalus treatment, as well as impact on further antitumoral management. Out of 28 identified patients, 23 patients presented with untreated hydrocephalus and 25 without histological diagnosis. One patient underwent open biopsy, and 24 received a neuroendoscopic biopsy with concomitant hydrocephalus treatment if necessary. Eighteen primary ETVs, 2 secondary ETVs, and 2 ventriculoperitoneal shunts (VPSs) were performed. Endoscopic biopsy had a diagnostic yield of 95.8% (23/24) and complication rates of 12.5% (transient) and 4.2% (permanent), respectively. ETV for hydrocephalus management was successful in 89.5% (17/19) with a median follow-up of more than 3 years. Following histological diagnosis, 8 patients (28.6%) underwent primary resection of their tumor. Another 9 patients underwent later-stage resection after either adjuvant treatment (n = 5) or for progressive disease during observation (n = 4). Eventually, 20 patients received adjuvant treatment and 7 were observed after primary management. One patient was lost to follow-up. Heterogeneity of pineal region tumor requires histological confirmation. Primary biopsy of pineal lesions should precede surgical resection since less than a third of patients needed primary surgical resection according to the German pediatric brain tumor protocols. Interdisciplinary decision making upfront any treatment is warranted in order to adequately guide treatment.

Microsurgical resection of pineal region tumors.

The extensive variety of possible histologic subtypes makes it imperative to establish a tissue diagnosis in patients with pineal region tumors. Management decisions regarding adjuvant therapy, prognosis, and follow-up strategies vary with the histologic diagnosis. Specialized surgical and stereotactic techniques have evolved to provide the neurosurgeon with an array of safe and effective options for obtaining a tissue diagnosis. Advanced microsurgical techniques combined with improved preoperative management and postoperative critical care methods have made aggressive surgical resection a mainstay of management. Aggressive surgical resection has resulted in excellent long-term prognoses for nearly all patients with benign tumors and a large percentage of patients with malignant tumors. However, pineal region surgery remains fraught with potential pitfalls, and these favorable results are dependent on an advanced level of surgical expertise.

Endoscopic-assisted interhemispheric parieto-occipital transtentorial approach for microsurgical resection of a pineal region tumor: operative video and technical nuances.

The angle of the straight sinus and tentorium cerebelli can often influence the choice of surgical approach to the pineal region. The supracerebellar infratentorial approach can be technically challenging and a relative contraindication in cases where the angle of the straight sinus and tentorium is very steep. Similarly, an occipital transtentorial approach, which uses a low occipital craniotomy at the junction of the superior sagittal sinus and transverse sinus, may not provide the best trajectory to the pineal region in patients with a steep tentorium. In addition, this approach often necessitates retraction on the occipital lobe to access the tentorial incisura and pineal region, which can increase the risk of visual compromise. In this operative video, the author demonstrates an alternative route using an endoscopic-assisted interhemispheric parieto-occipital transtentorial approach to a pineal region tumor in a patient with a steep straight sinus and tentorium. The approach provided a shorter route and more direct trajectory to the tumor at the tentorial incisura, and avoided direct fixed retraction on the occipital lobe when performed using the lateral position, thereby minimizing visual complications. This video atlas demonstrates the operative technique and surgical nuances, including the application of endoscopic-assisted microsurgical resection and operative pearls for preservation of the deep cerebral veins. In summary, the parieto-occipital transtentorial approach with endoscopic assistance is an important approach in the armamentarium for surgical management of pineal region tumors. The video can be found here: https://youtu.be/Ph4veG14aTk .

Endoscopic-assisted posterior interhemispheric retrocallosal transfalcine approach for microsurgical resection of a pineal region falcotentorial meningioma: operative video and technical nuances.

Falcotentorial meningiomas are rare tumors of the pineal region that arise from the dural folds where the falx and tentorium meet and are often intimately related to the vein of Galen and straight sinus. These lesions often present with signs and symptoms related to hydrocephalus and brainstem compression. Surgical resection of falcotentorial meningiomas remains the definitive treatment, with a variety of surgical approaches used to resect these lesions. The choice of approach depends on several factors, including the size and location of the tumor relative to the vein of Galen complex. Falcotentorial meningiomas can be technically challenging to remove with significant risk of morbidity because of the close proximity to and occasional invasion of the vein of Galen and straight sinus. In this operative video, the authors demonstrate an illustrative step-by-step technique for endoscopic-assisted microsurgical resection of a falcotentorial meningioma using the posterior interhemispheric retrocallosal transfalcine approach for a superiorly positioned falcotentorial meningioma. The surgical nuances are discussed, including the surgical anatomy, gravity-assisted interhemispheric approach in the lateral position, retrocallosal dissection, transfalcine exposure, tumor removal, and preservation of the vein of Galen complex. In summary, the posterior interhemispheric retrocallosal transfalcine approach is a useful surgical strategy for select superiorly positioned falcotentorial meningiomas. The video can be found here: https://youtu.be/d8mdunsRacs .

Purely endoscopic resection of pineal region tumors using infratentorial supracerebellar approach: How I do it.

BACKGROUND: Infratentorial supracerebellar approach via microscope still has some limitations in resection of pineal region tumors. METHODS: The authors describe a purely endoscopic infratentorial supracerebellar approach for resection of pineal region tumors with matched air-driven arm and navigation. The lateral oblique position is adopted. The same bimanual microsurgical techniques are utilized in this endoscopic approach with panoramic view and satisfying comfort. CONCLUSIONS: Purely endoscopic resection of pineal region tumors using infratentorial supracerebellar approach is feasible. It may be considered as an alternative approach for certain pineal region tumors.