Endoscopic Endonasal Resection Research Articles

How I do it: Endoscopic endonasal resection of the medial wall of the cavernous sinus.

Resection of the medial wall of the cavernous sinus (MWCSR) is a growing surgical maneuver for the radical removal of pituitary adenomas. We present a simple modification of the technique following the two dural layers of the floor of the sella turcica, allowing for early identification of the medial wall and simplifying dissection. We support this technique with an anatomical analysis on cadaveric specimens and clarifying dissection images. Recognition and dissection of the dural unfolding of the floor of the sella turcica are "key points" that lower the risk and facilitate the MWCSR.

Surgical outcome of endoscopic endonasal approach as a modality of management for large and giant pituitary adenomas: a retrospective case series

BackgroundLarge and giant pituitary adenomas (defined as tumors of maximal diameter ≥ 3–3.9 cm and ≥ 4 cm, respectively) present considerable surgical challenges regarding the extent of resection and perioperative morbidity. Endoscopic endonasal resection is considered the most effective treatment for pituitary adenomas. It allows for better visualization, maneuverability, and access to distant and lateral tumor compartments, ultimately enhancing the extent of resection. This article evaluates our initial experience with endoscopic endonasal resection of large and giant pituitary adenomas. The clinical outcomes, perioperative complications, and extent of tumor resection would be specifically addressed.Patients and methodsThe primary goal of surgery was to decompress the optic pathways, and the secondary goals were to achieve maximal safe resection and hormonal control in hormone-secreting adenomas. The degree of tumor resection was classified as gross-total resection (100%), near-total resection (90–100%), subtotal resection (70–90%), and partial resection (< 70%).Results42 patients were included in this study. A good visual outcome achieved with 80% improvement in visual symptoms. Gross-total resection (GTR) was achieved in 19 patients (45.2%), near-total resection (NTR) was achieved in 12 patients (28.6%), subtotal resection (STR) in 6 patients (14.3%), and partial resection in the remaining 5 patients (11.9%). Subgroup analysis revealed that GTR, NTR rates were higher in large, compared to giant tumors. GTR, NTR rates of large adenomas were 59.3%, and 29.6%, compared to 20%, and 26.7% in giant adenomas respectively (p-value: 0.01428). Surgical complications were observed in 19 patients (45.2%) with CSF leakage being the most common complication (11 patients, 26.2%). Post-operative diabetes insipidus was observed in 5 patients (11.9%), major vascular injury in one case (2.4%), transient post-op 6th nerve palsy observed in 3 patients (7.1%), while two patients (4.8%) presented with post-operative paranasal sinuses infection.ConclusionsEndoscopic endonasal transsphenoidal resection of large and giant pituitary adenomas is a safe and efficient procedure. Large adenomas (3–3.9 cm) have excellent resection rates and lower complications than giant adenomas (≥ 4 cm), which may require extending our approach to achieve more tumor resection rates in the future. However, only adequate resection of these giant adenomas can be enough to achieve the main surgical goals of visual improvement, hormonal control, and decompression of surrounding structures.

Single Center Neurosurgical Outcomes and Trends in Endoscopic Endonasal Resection of 297 Sellar/Suprasellar Tumors Stratified by Duration of Neurosurgical Career

Endoscopic endonasal transsphenoidal surgery (EETS) is a common treatment for sellar and suprasellar tumors. While endoscopic training has improved over the years and formal fellowship training is now broadly available, the operative nuances of EETS conjectures the existence a learning curve as a neurosurgeon matures with experience. We aim to evaluate operative outcomes of three different experience levels of neurosurgeons over time at a single institution. We reviewed all adult patients who underwent EETS at Loyola University Medical Center by three early career, one mid-career, and two late career neurosurgeons from 2007 to 2023. A comparative assessment of patient demographics, tumor features, and surgical outcomes was done using metrics such as length of surgery, rates of gross total resection (GTR) and symptomatic improvement (SI), new postoperative steroid dependence, and development of diabetes insipidus (DI). T-tests and Chi-Square were used to statistically evaluate the study cohorts. A total of 297 patients underwent EETS. One hundred and three (35%) were operated on by an early career, 122 (41%) by a mid-career, and 72 (24%) by a late career neurosurgeon. Late-career surgeons had shorter operation times (144 vs. 180 minutes with early and mid-career, p=0.029) and increased GTR rates (p=0.008). There were no significant differences between the SI rates amongst various surgeon experience levels. Although not statistically significant, early-career neurosurgeons had lower rates of new postoperative steroid dependence. Patients of early career surgeons experienced significantly less DI (15% vs 40%, p=0.004). Late-career neurosurgeons had shorter operation lengths, achieved higher rates of GTR, and their patients experienced significantly higher rates of DI. Overall outcomes remained stable throughout the course of 16 years between different surgeon experience levels.

Endoscopic endonasal resection of symptomatic Rathke's cleft cysts: outcomes of the strategy to maintain the fenestration open.

The study intends to clarify the optimal endoscopic endonasal surgical strategy for symptomatic Rathke's cleft cysts (RCCs). We retrospectively analyzed patients with RCCs that underwent EEA surgery. The strategy for surgical and reconstruction method selection was presented. Patients were split into groups of fenestration open or closed. Pre- and postoperative symptoms, imaging, ophthalmologic, and endocrinologic exams were reviewed. The incidence of complications and the recurrence rates were determined. The 75 individuals were all received primary operations. The fenestration closed group contained 32 cases, while the fenestration open group contained 43 cases. The median follow-up period was 39 months. The three primary complaints were headache (n = 51, 68.00%), vision impairment (n = 45, 60.00%), and pituitary dysfunction (n = 16, 21.33%). Of the 51 patients with preoperative headaches, 48 (94.12%) reported improvement in their symptoms following surgery. Twenty-three out of 45 patients (51.11%) experienced an improvement in visual impairment. Pituitary dysfunction was found improved in 14 out of 16 individuals (87.50%). There was no discernible difference in the rate of symptom alleviation between both groups. There were three patients (3/75, 4.00%) had cyst reaccumulation. One of them (1/75, 1.33%), which needed reoperation, was healed using pterional approach. In term of complications, cerebral infections occurred in two patients (2/75, 2.67%). Both of them recovered after antibiotic treatment. No postoperative cerebrospinal fluid rhinorrhea occurred. One patient (1/75, 1.33%) in the open group experienced epistaxis. There was no persistent hypopituitarism or diabetes insipidus (DI). Analysis of headache related factors showed that the presence of wax like nodules was related to it. RCC was successfully treated with endoscopic endonasal surgery with few problems when the fenestration was kept as open as feasible. Preoperative identification of T2WI hypointense nodules may be a potential reference factor for surgical indication.

Taste dysfunction after endoscopic endonasal resection of olfactory groove meningioma: Case series and review of the literature

PurposeThe incidence of ageusia and dysgeusia after endoscopic endonasal (EEA) resection of olfactory groove meningioma (OGM) is not well established despite recognized impairment in olfactory function. MethodsWe retrospectively administered a validated taste and smell survey to patients undergoing EEA for resection of OGM at two institutions. Demographics and clinical characteristics were collected and survey responses were analyzed. ResultsTwelve patients completed the survey. The median time from surgery was 24 months. The average total complaint score was 5.5 out of 16 [0–13]. All patients reported a change in sense of smell while only 42 % reported a change in sense of taste. Taste changes did not consistently associate with laterality or size of the neoplasm. Significant heterogeneity existed when rating severity of symptoms. ConclusionsTo our knowledge this is the first case series examining taste changes after EEA resection of OGM. Despite universal olfactory dysfunction, only a minority of patients reported a change in their sense of taste. Our findings may improve patient counseling and expectations after surgery.

Modified Function-Preserving Endoscopic Endonasal Extracapsular Resection of a Large Orbital Apex Cavernous Hemangioma.

Various invasive oculoplastic procedures are commonly utilized to control the rectus muscles and widen the surgical corridor through the endoscopic endonasal removal of large orbital apex cavernous hemangiomas (OACHs). They require additional transconjunctival incision, rectus muscle insertional retraction, or muscle deinsertion at the globe that might not be safe and lead to prolonged postoperative extraocular muscle dysfunction. In this article, the authors described a modified 3-handed extracapsular technique for the resection of a large OACH without an additional procedure for rectus muscle control. The aim is to achieve a safe gross total tumor removal while minimizing the procedure-related complications. An intraoperative video is included, along with a stepwise cadaveric dissection relevant to the approach. A 71-year-old female presented with progressive left-sided blurred vision, binocular diplopia, and mild proptosis. Contrast-enhanced brain MRI revealed a large heterogeneous enhanced inferomedial intraconal mass in the left orbital apex, mostly consistent with cavernous hemangioma. Gross total tumor removal was achieved through a modified 3-handed endoscopic endonasal extracapsular approach. The diplopia was resolved, and significant visual improvement was achieved. Computed tomography scan demonstrated complete tumor removal, and histological examination confirmed the diagnosis. Endoscopic endonasal resection of large OACH can be feasibly performed by using a modified 3-handed extracapsular technique through the generous use of Q-tip swab applicators within the natural separation plane around the tumor capsule and a sequential traction-countertraction method. Subsequently, a gross total removal and optimal postoperative functional outcome are attainable through minimal rectus muscle fiber violation and intraconal fat manipulation.

500 Endoscopic Endonasal Resection of the Medial Wall of the Cavernous Sinus: Initial Experience and Impact on Pituitary Surgery Outcomes

INTRODUCTION: Invasion of the medial wall of the cavernous sinus (CS) by pituitary tumors is a factor associated with persistence of disease and subtotal resection of these tumors. Resection of the medial wall of the CSis therefore an option for maximum resection of such tumors, however, there is concern with potential complications associated with this technique and at this time, limited data is available in the literature. METHODS: Single center retrospective study evaluating patients that underwent endoscopic endonasal resection of pituitary adenomas and resection of the medial wall of the CS, between January 2022 and February 2023. Extent of resection, remission rates, complications and histopathological diagnosis were assessed. RESULTS: Out of a population of 120 pituitary surgeries, sixteen cases were eligible for this study. 5 (31.2%) patients had non-functional adenomas, and 11 (68.7%) had functional adenomas, including 4 adrenocorticotropic hormone, 3 prolactin, 3 growth-hormone, 1 pluri-hormonal (GH and prolactin)—secreting tumors. Complete tumor resection, based on intraoperative impression and postoperative MRI, was achieved in all cases. At last follow-up, complete biochemical remission (using current criteria) was seen in 11 cases (100%) of functional adenomas. One case developed pulmonary embolism and another one sino-nasal infection postoperatively. No fatalities, carotid injuries or cranial nerve palsies were reported. CONCLUSIONS: Resection of the medial wall of the cavernous sins, performed when there is potential tumor extension into the medial wall, is associated with high rates of disease control. It is particularly useful in cases of functioning but also has a role in non-functional adenomas adherent to the medial wall of the CS. Long term follow up is necessary to evaluate the durability of these results.

Clinical application of reserved gastric tube in neuroendoscopic endonasal surgery for pituitary tumor.

The neuroendoscopic approach has the advantages of a clear operative field, convenient tumor removal, and less damage, and is the development direction of modern neurosurgery. At present, transnasal surgery for sphenoidal pituitary tumor is widely used. But it has been found in clinical practice that some patients with this type of surgery may experience post-operative nausea and vomiting and other discomforts. To explore the effect of reserved gastric tube application in the neuroendoscopic endonasal resection of pituitary tumors. A total of 60 patients who underwent pituitary adenoma resection via the endoscopic endonasal approach were selected and randomly divided into the experimental and control groups, with 30 in each group. Experimental group: After anesthesia, a gastric tube was placed through the mouth under direct vision using a visual laryngoscope, and the fluid accumulated in the oropharynx was suctioned intermittently with low negative pressure throughout the whole process after nasal disinfection, during the operation, and when the patient recovered from anesthesia. Control group: Given the routine intraoperative care, no gastric tube was left. The number of cases of nausea/vomiting/aspiration within 24 h post-operation was counted and compared between the two groups; the scores of pharyngalgia after waking up, 6 h post-operation, and 24 h post-operation. The frequency of postoperative cerebrospinal fluid leakage and intracranial infection were compared. The hospitalization days of the two groups were statistically compared. The times of postoperative nausea and vomiting in the experimental group were lower than that in the control group, and the difference in the incidence of nausea was statistically significant (P < 0.05). After the patient woke up, the scores of sore throat 6 h after the operation and 24 h after operation were lower than those in the control group, and the difference was statistically significant (P < 0.05). The number of cases of postoperative cerebrospinal fluid leakage and intracranial infection was higher than that of the control group, but there was no statistically significant difference from the control group (P > 0.05). The hospitalization days of the experimental group was lower than that of the control group, and the difference was statistically significant (P < 0.05). Reserving a gastric tube in the endoscopic endonasal resection of pituitary tumors, combined with intraoperative and postoperative gastrointestinal decompression, can effectively reduce the incidence of nausea, reduce the number of vomiting and aspiration in patients, and reduce the complications of sore throat The incidence rate shortened the hospitalization days of the patients.

Endoscopic endonasal approach for olfactory groove meningioma resection: Strategies and outcomes in a retrospective case series

ObjectiveThough the endoscopic endonasal approach (EEA) is a widely accepted treatment for skull base tumors, the specific use of EEA for olfactory groove meningiomas (OGMs) is debated, with variable outcomes reported in the literature. We review the surgical results of OGM resections for one surgeon including the operative approach, surgical nuances, and outcomes, with a focus on factors relating to patient selection which favor EEA over transcranial approaches. MethodsWe retrospectively reviewed thirteen cases of endoscopic endonasal resection of olfactory groove meningiomas. Patient characteristics, clinical characteristics, surgical outcomes, and complications were analyzed. Extent of resection was determined based on volumetric analysis of pre- and postoperative MRI. ResultsAnatomic characteristics that render a tumor difficult to access fully are lateral extension beyond the mid-orbit and anterior extension to the falx. Simpson Grade I resection was achieved in 11/13 (84.6 %) cases. Mean pre-operative tumor volume was 8.99 cm3 (range 2.19–16.79 cm3), and 92 % of tumors were WHO grade I. We demonstrate 2 cases of smell preservation, possible with small unilateral tumors and tumors that are confined to either the anterior or posterior portion of the cribriform plate. The post-operative CSF leak rate was 7.7 %, without prophylactic lumbar CSF drainage. The mortality rate was 7.7 % (n = 1) after infectious complications following CSF leak. ConclusionsEndoscopic endonasal resection of olfactory groove meningiomas is an effective and safe operative method with outcomes and complication rates comparable to transcranial approaches. Key considerations include careful patient selection and familiarity with technical nuances of endoscopic endonasal approach for this specific tumor type.

Endoscopic endonasal approach for skull base chordoma

BackgroundChordoma is a rare slow-growing malignant bone tumor that arises from embryonic notochordal remnants in the axial skeleton. Clival chordomas have a high propensity for extension through the skull base and a high proclivity for recurrence. Recently, resection of skull base chordomas through the endoscopic transnasal approach has become the standard way of managing these lesions with the new advancements in neuronavigation and reconstructive techniques in skull base surgery.MethodsIt is a retrospective study of all patients with clival chordoma that were operated upon using endoscopic endonasal resection at the Main Alexandria University Hospital during the period from March 2008 to April 2013. The extent of surgical resection was assessed intraoperatively and confirmed by the postoperative MRI study performed 8–12 weeks, 6 months, and yearly after the surgery.ResultsTwelve patients with clival chordoma were managed by endoscopic transnasal resection. Gross total resection confirmed by postoperative MRI was achieved in four cases, subtotal resection in six cases, and partial resection in two cases of clival chordoma. In cases where gross total resection was not achieved, residual tumors were adherent to vital neurovascular structures as confirmed with the utilization of an intraoperative imaging navigation device. A study of postoperative complications and possible recurrence was done for all cases.ConclusionsThe findings of this study highlight the significance of gross total resection as a major determinant for preventing the recurrence of chordoma. Our findings also support the validity of the endoscopic approach for the management of clival chordoma especially when the approach is tailored based on the site and extent of the tumor.

Pediatric sellar teratoma – Case report and review of the literature

BackgroundIntracranial teratoma represents a rare neoplasm, occurring predominantly during childhood. Characteristic symptoms depend on the location but are mainly hydrocephalus, visual disturbances, hypopituitarism, and diabetes insipidus. Initial diagnosis can be challenging due to similar radiological features in both teratomas and other lesions such as craniopharyngiomas. Gross total resection is recommended if feasible and associated with a good prognosis.Case descriptionA 10-year-old girl presented with newly diagnosed growth retardation, fatigue, cephalgia and bilateral hemianopia. Further laboratory analysis confirmed central hypothyroidism and hypercortisolism. Cranial magnetic resonance imaging showed a cystic space-occupying lesion in the sellar and suprasellar compartment with compression of the optic chiasm without hydrocephalus present, suspicious of craniopharyngioma. Subsequently, an endonasal endoscopic transsphenoidal near-total tumor resection with decompression of the optic chiasm was performed. During postoperative recovery the patient developed transient diabetes insipidus, the bilateral hemianopia remained unchanged. The patient could be discharged in a stable condition, while hormone replacement for multiple pituitary hormone deficiency was required. Surprisingly, histopathology revealed conspicuous areas of skin with formation of hairs and squamous epithelia, compatible with a mature teratoma.ConclusionsWe present an extremely rare case of pediatric sellar teratoma originating from the pituitary gland and a review of literature focusing on the variation in presentation and treatment. Sellar teratomas are often mistaken for craniopharyngioma due to their similar radiographic appearances. However, the primary goal of treatment for both pathologies is to decompress eloquent surrounding structures such as the optic tract, and if applicable, resolution of hydrocephalus while avoiding damage to the pituitary stalk and especially the hypothalamic structures. If feasible, the aim of surgery should be gross total resection.

Skull Base Reconstruction by Subsite after Sinonasal Malignancy Resection.

Reconstruction after the resection of sinonasal malignancies is complex and primarily dependent on the defect size and location. While the reconstructive paradigm for sellar mass resection is well delineated, the challenges associated with reconstruction after sinonasal malignancy resection are less well described. This narrative review will address the goals of reconstruction after both endonasal endoscopic and open sinonasal malignancy resection and reconstructive options specific to these subsites. The goals of reconstruction include repairing cerebrospinal fluid leaks, restoring sinonasal function, providing a nasal airway, and optimizing the patient's quality of life. These goals are often complicated by the anatomic nuances of each involved sinus. In this review, we will discuss the methods of reconstruction specific to each sinonasal subsite and describe the factors that guide choosing the optimal reconstructive technique.

Outcomes of the Endoscopic Endonasal Approach for the Treatment of Clival Chordomas: A Single-Center Experience

Abstract Objective Chordoma is a low-grade malignant tumor that originates from the remnant tissue of the embryonic notochord. Postoperative or definitive radiotherapy (RT) has been used to enhance local control. This study aims to assess the outcomes of the expanded endoscopic endonasal approach (EEA) for maximal removal of clival chordomas followed by RT for visualized residual or tumor recurrence. Materials and Methods A retrospective review was performed on consecutive patients with clival chordoma who underwent endoscopic endonasal resection in the otorhinolaryngology and neurosurgery departments, between 2016 and 2021. We included all patients with pathologically confirmed clival chordoma who were treated using the EEA. Patients who underwent combined external and endoscopic approaches or transcranial surgery were excluded. Results Seventeen patients were included in this study. Most of them had tumors located in the middle clivus. Regarding RT, the majority of patients underwent postoperative RT. Almost half of them underwent CyberKnife (CK) RT. None of them had severe toxicities (grade 3 or higher). Three patients died, resulting in a mortality rate of 17.6% none of them related to radiation side effect. The 2-year overall survival was 82.4% (mean standard error [SE] = 1.765, 95% confidence interval [CI] = 1.505–2.024), and the progression-free survival (PFS) was 76.5% (mean SE = 3.403, 95% CI = 2.791–4.016). No distal metastasis was reported in our series. Conclusion This series demonstrates that expanded endoscopic endonasal approach (EEA) for the resection of skull base chordomas, followed by CyberKnife radiosurgery, presents a viable alternative to proton beam therapy; however, further research is necessary to directly compare these modalities.

An institutional experience in applying quality improvement measures to pituitary surgery: clinical and resource implications.

The aim of this study was to report the authors' experience developing a Lean Six Sigma clinical care pathway (CCP) for endoscopic endonasal transsphenoidal operations. Using Lean Six Sigma quality improvement principles-including the define, measure, analyze, improve, and control framework-the authors developed a CCP for endoscopic endonasal transsphenoidal operations, incorporating preoperative, intraoperative, and inpatient and outpatient postoperative phases of care. Efficacy and quality metrics were defined as postoperative length of stay (LOS), presentation to the emergency department (ED) or readmission within 30 days of discharge, and hospital charges. The study included all adult patients who underwent elective endoscopic endonasal resection for pituitary adenoma, Rathke's cleft cyst, craniopharyngioma, pituicytoma, or arachnoid cyst during the sampling period (April 1, 2018, to December 31, 2022). Two hundred twenty-eight patients met criteria and were included; 94 were treated before and 134 were treated after implementation of the CCP. Differences between groups in age, gender, race, BMI, American Society of Anesthesiologists classification, geographic distribution, preoperative serum sodium, tumor size, adenoma functional status, and prior surgery were not significant. The mean postoperative LOS significantly decreased from 4.5 to 1.7 days following CCP implementation (p < 0.0001); LOS variability also decreased, with the standard deviation declining from 3.1 to 1.5 days. The proportion of patients discharged on postoperative day (POD) 1 significantly increased from 0% to 61.9% (p < 0.0001). Fewer than one-quarter of the patients (23.4%) were discharged by POD 2 prior to the CCP, while 88.8% of were discharged by POD 2 after CCP implementation (p < 0.0001). Rates of 30-day ED presentations or readmissions were not significantly different (2.1% vs 6.0%, p = 0.20, and 7.5% vs 6.7%, p > 0.99, respectively). Mean per-patient hospital costs declined from $38,326 to $26,289 (p < 0.0001), with an associated change in cost variability from a standard deviation of $16,716 to $12,498. CCP implementation significantly improved LOS and costs of endoscopic endonasal resection, without adversely impacting postoperative ED presentations or readmissions.

Portable MRI to assess optic chiasm decompression after endoscopic endonasal resection of sellar and suprasellar lesions.

Low-field portable MRI (pMRI) is a recent technological advancement with potential for broad applications. Compared with conventional MRI, pMRI is less resource-intensive with regard to operational costs and scan time. The application of pMRI in neurosurgical oncology has not been previously described. The goal of this study was to demonstrate the efficacy of pMRI in assessing optic nerve decompression after endoscopic endonasal surgery for sellar and suprasellar pathologies. Patients who underwent endoscopic endonasal surgery for sellar and suprasellar lesions at a single institution and for whom pMRI and routine MRI were performed postoperatively were retrospectively reviewed to compare the two imaging systems. To assess the relative resolution of pMRI compared with MRI, the distance from the optic chiasm to the top of the third ventricle was measured, and the measurements were compared between paired equivalent slices on T2-weighted coronal images. The inter- and intrarater correlations were analyzed. Twelve patients were included in this study (10 with pituitary adenomas and 2 with craniopharyngiomas) with varying degrees of optic chiasm compression on preoperative imaging. Measurements were averaged across raters before calculating agreement between pMRI and MRI, which demonstrated significant interrater reliability (intraclass correlation coefficient [ICC] = 0.78, p < 0.01). Agreement between raters within the pMRI measurements was also significantly reliable (ICC = 0.93, p < 0.01). Finally, a linear mixed-effects model was specified to demonstrate that MRI measurement could be predicted using the pMRI measurement with the patient and rater set as random effects (pMRI β coefficient = 0.80, p < 0.01). The results of this study suggest that resolution of pMRI is comparable to that of conventional MRI in assessing the optic chiasm position in relation to the third ventricle. Portable MRI sufficiently demonstrates decompression of the optic chiasm after endoscopic endonasal surgery. It can be an alternative strategy in cases in which cost, scan-time considerations, or lack of intraoperative MRI availability may preclude the ability to assess adequate optic nerve decompression after endoscopic endonasal surgery for sellar and suprasellar lesions.

Predictors of extent of resection and recurrence following endoscopic endonasal resection of craniopharyngioma.

Craniopharyngioma is a benign but surgically challenging brain tumor. Controversies exist regarding its ideal treatment strategy, goals of surgery, efficacy of radiation, and the long-term outcomes of these decisions. The authors of this study performed a detailed analysis of factors predictive of the extent of resection and recurrence in large series of craniopharyngiomas removed via an endoscopic endonasal approach (EEA) with long-term follow-up. From a prospective database of all EEAs done at Weill Cornell Medical College by the senior author from 2004 to 2022, a consecutive series of histologically proven craniopharyngiomas were identified. Gross-total resection (GTR) was generally the goal of surgery. Radiation was often given if GTR had not been achieved. The stalk was preserved if not infiltrated with tumor but was sacrificed to achieve GTR. Intentional subtotal resection (STR) was performed in select cases to avoid hypothalamic injury. Among the 111 identified cases were 88 adults and 23 children. Newly diagnosed cases comprised 58.6% of the series. GTR was attempted in 77.5% of the patients and among those cases was achieved in 89.5% of treatment-naive tumors and 72.4% of recurrent tumors. An inability to achieve GTR was predicted by prior surgical treatment (OR 0.13, 95% CI 0.03-0.6, p = 0.009), tumor diameter ≥ 3.5 cm (OR 0.11, 95% CI 0.02-0.53, p = 0.006), and encasement of the optic nerve or a major artery (OR 0.11, 95% CI 0.01-0.8, p = 0.03). GTR with stalk preservation maintained some anterior pituitary function in 64.5% of cases and prevented diabetes insipidus in 25.8%. After a median follow-up of 51 months (IQR 17-80 months), the recurrence rate after GTR was 12.5% compared with 38.5% after non-GTR. The median recurrence-free survival was 5.5 years after STR, 8.3 years after near-total resection (≥ 98%), and not reached after GTR (p = 0.004, log-rank test). GTR was the strongest predictor of recurrence-free survival (OR 0.09, 95% CI 0.02-0.42, p = 0.002), whereas radiation did not show a statistically significant impact (OR 1.17, 95% CI 0.45-3.08). In GTR cases, the recurrence rate was higher if the stalk had been preserved (22.6%) as opposed to a sacrificed stalk (4.9%; OR 5.69, 95% CI 1.09-29.67). The study data show that GTR should be the goal of surgery in craniopharyngiomas if it can be achieved safely. Although stalk preservation can maintain some endocrine function, the risk of recurrence is higher in such cases. Radiation may not be as effective as previously reported.

Decision-Making in Clival Mass Lesions: Risk Factors for Malignant Disease and an Illustrative Case Example.

Introduction Clival tumors are rare and heterogeneous. Although some benign prototypical sellar lesions may present as clival tumors, the likelihood of malignant disease is higher. Here we define a novel algorithm for the workup and management of clival masses through an illustrative case of colorectal adenocarcinoma metastasis to the clivus. Methods In this case report, the best practice guidelines for managing clival masses are described through a literature review and refined by senior author consensus. We conducted a focused systematic review to characterize the present case in the context of clival metastasis from gastrointestinal malignancy. Results An 83-year-old woman presented with 4 weeks of headaches and blurry vision. Examination revealed partial right abducens and left oculomotor palsies. Magnetic resonance imaging (MRI) identified a large, weakly enhancing sellar and clival mass with sphenoid sinus extension. An aggressive subtotal endoscopic endonasal resection was performed with removal of all sphenoid, clival, and sellar disease without cavernous sinus wall resection. Pathology confirmed colorectal adenocarcinoma; computed tomography (CT) imaging identified an ascending colon mass with metastases to the liver and mesenteric nodes. Palliative oncologic therapies were recommended, but she elected hospice, and died 3 months after initial presentation. Gastrointestinal clival metastases are exceedingly rare among sellar and clival pathologies, with eight prior cases reported, most of which presented with diplopia from abducens nerve involvement. Conclusion Clival masses are uncommon skull base lesions that are associated with more aggressive diseases. We present a consolidated framework for decision-making in these challenging patients, alongside an unusual case example that illustrates the importance of increased suspicion for malignant clinical entities in this setting.

Abstract PO-099: Short-term outcomes of an extended endoscopic endonasal resection of a clival giant cell tumor with adjuvant RANK-L inhibitor therapy: Case report

Abstract Background Clival giant cell tumors (GiCT) are rare neoplasms that commonly target the epiphysis. Recently, skull base GiCTs have been reported, predominantly in the sphenoid and temporal bones. Although typically benign, GiCTs of the skull-base can cause neurologic deficits due to compression of cranial nerves or intracranial contents. The efficacy of adjuvant chemotherapy in treating GiCTs is not known. One potential treatment option neoplastic mononuclear stromal cells in GiCTs express NF-κB ligands (RANK-L), which can be therapeutically targeted with Denosumab, a monoclonal antibody against RANK-L. Here, we describe the case of a GiCT invasive to the clivus, an extended endoscopic endonasal resection of the tumor, and management of the lesion with Denosumab. Methods A retrospective chart review was performed on the patient of interest. Magnetic resonance imaging (MRI) and computed tomography (CT) scans were used to assess disease growth and response to surgical and therapeutic intervention. Case presentation A previously healthy seventeen-year-old female presented with headaches and numbness of the left V2 and V3. A diagnosis of a clival giant cell tumor was confirmed with strict pathologic, radiographic, and clinical correlation. She was found to have a clival mass extending into the sphenoid sinus. Surgical excision was performed by both the otolaryngology and neurosurgery departments at a single institution. She underwent an extended endoscopic endonasal resection of the clival mass. Following surgery, the numbness on the left V2 and V3 distribution improved. She occasionally reported bilateral V3 distribution symptoms without definite anatomic correlates for right sided complaints. Due to the presence of residual tumor, we recommended adjunctive medical therapy. We performed adjunctive medical therapy with Denosumab, a RANKL inhibitor. Discussion When complete surgical excision with negative margins is not feasible in lesions of the skull base, adjuvant treatment is commonly required to achieve local disease control. Our case demonstrates the efficacy of a combined approach where surgery is used to achieve a histologic diagnosis, decompression and evaluate for respectability. Adjuvant medical therapy using RANKL inhibitors is a promising approach that may be effective to achieve lifelong disease control but requires continued maintenance on therapy. Citation Format: Myra A. Zaheer, Abhisri Ramesh, Aadit P. Mehta, Adriana S. Fonseca, Daniel A. Donoho. Short-term outcomes of an extended endoscopic endonasal resection of a clival giant cell tumor with adjuvant RANK-L inhibitor therapy: Case report [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Innovating through Basic, Clinical, and Translational Research; 2023 Jul 7-8; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2023;29(18_Suppl):Abstract nr PO-099.

Triphasic response after endoscopic craniopharyngioma resection and its dependency on infundibular preservation or sacrifice.

Surgery is the primary treatment for craniopharyngioma with the preservation of hypothalamic function of paramount importance. Infundibular preservation is debated, as maximal resection decreases recurrence rates but causes hypopituitarism. A triphasic response of diabetes insipidus (DI), syndrome of inappropriate antidiuretic hormone secretion (SIADH), and recurrent DI has been described after pituitary surgery, but the impact of infundibular preservation on the triphasic response following craniopharyngioma resection has not been well established. The authors' objective was to assess postoperative fluid and sodium balance and differences in ADH imbalance management following endonasal craniopharyngioma resection based on infundibular transection status. This is a retrospective cohort study of 19 patients with craniopharyngioma treated with endoscopic endonasal resection between 2014 and 2021. Resection was dichotomized into infundibular transection or preservation. Postoperative triphasic response, time to DI, and time to ADH replacement were compared using Fisher's exact test and Kaplan-Meier analysis. Based on surgeon impression, 10 patients had infundibular transection and 9 had infundibular preservation. Overall, 16 patients experienced DI, 12 experienced persistent DI, and 6 experienced SIADH. A postoperative triphasic response occurred in 40% (n = 4) of transection patients without preoperative DI and 11% (n = 1) of preservation patients without preoperative DI. The median time to postoperative DI (0.5 vs 18.0 hours, p = 0.022) and median time to ADH replacement therapy (4.5 vs 24 hours, p = 0.0004) were significantly shorter in the transection group than in the preservation group. Following endonasal craniopharyngioma resection, the triphasic response occurs in nearly half of infundibular transection cases. DI begins earlier with infundibular transection. On the basis of the study findings in which no patients met the criteria for SIADH or were endocrinologically unstable after postoperative day 6, it is reasonable to suggest that otherwise stable patients can be discharged at or before postoperative day 6 when ADH fluctuations have normalized and endocrinopathy is appropriately managed with oral desmopressin. Infundibular transection status may impact postoperative hormonal replacement strategies, but additional studies should evaluate their efficacies.

Combined endoscopic endonasal and sublabial transmaxillary approaches for resection of intracranially extended juvenile nasopharyngeal angiofibroma.

Juvenile nasopharyngeal angiofibromas (JNAs) are rare, benign, and locally invasive nasopharyngeal tumors. Endoscopic endonasal resection is effective, non-invasive, with low complication rates. Until recently, endoscopic resection was not suitable for intracranially invasive tumors. We describe resection steps of an intracranially extending JNA with a combined endoscopic endonasal and endoscopic-assisted sublabial transmaxillary approaches. Indications, advantages, and approach-specific complications are also discussed. The main surgical steps are shown in an operative video. Surgical excision of JNAs by a combined endoscopic endonasal and sublabial transmaxillary approaches represents a safe and effective treatment for selected intracranially invasive JNA.