Anatomic relations of the arachnoidea around the pituitary stalk: relevance for surgical removal of craniopharyngiomas

Topography and Radiological Variables as Ancillary Parameters for Evaluating Tissue Adherence, Hypothalamic-Pituitary Dysfunction, and Recurrence in Craniopharyngioma: An Integrated Multidisciplinary Overview

Craniopharyngiomas continue to present a challenge in clinical practice due to their heterogeneity and unpredictable adherence to vital neurovascular structures, particularly the hypothalamus. This results in different degrees of hypothalamus-pituitary axis dysfunction and a lack of uniform consensus and treatment guidelines regarding optimal management. MRI and CT are complementary techniques in the preoperative diagnostic phase, enabling the precise definition of craniopharyngioma size, shape, and consistency, as well as guiding classification into histopathological subtypes and topographical categories. Meanwhile, MRI plays a crucial role in the immediate postoperative period and follow-up stages by identifying treatment-related changes and residual tumors. This pictorial essay aims to provide an overview of the role of imaging in identifying variables indicative of the adherence degree to the hypothalamus, hypothalamic-pituitary dysfunction, the extent of surgical excision, and prognosis. For a more comprehensive assessment, we choose to distinguish the following two scenarios: (1) the initial diagnosis phase, where we primarily discuss the role of radiological variables predictive of adhesions to the surrounding neurovascular structures and axis dysfunction which may influence the choice of surgical resection; (2) the early post-treatment follow-up phase, where we discuss the interpretation of treatment-related changes that impact outcomes.

Extended endoscopic endonasal approach to the chiasmatic cistern: An anatomical study of the arachnoid

This paper studied the arachnoid of the chiasmatic cistern (CC) and the methods for increasing the exposure of the CC from an endoscopic perspective. Eight anatomical specimens with vascular injection were used for endoscopic endonasal dissection. The anatomical characteristics of the CC were studied and documented, and anatomical measurements were collected. The CC is an unpaired five-walled arachnoid cistern located between the optic nerve, optic chiasm, and the diaphragma sellae. The average exposed area of the CC before the anterior intercavernous sinus (AICS) was transected was 66.67 ± 33.76 mm2 . After the AICS was transected and the pituitary gland (PG) was mobilized, the average exposed area of the CC was 95.90 ± 45.48 mm2 . The CC has five walls and a complex neurovascular structure. It is located in a critical anatomical position. The transection of the AICS and mobilization of the PG or the selective sacrifice of the descending branch of the superior hypophyseal artery can improve the operative field.

Predictive Factors for Pediatric Craniopharyngioma Recurrence: An Extensive Narrative Review

Despite being classified as benign tumors, craniopharyngiomas (CPs) are associated with significant morbidity and mortality due to their location, growth pattern, and tendency to recur. Two types can be identified depending on age distribution, morphology, and growth pattern, adamantinomatous and papillary. The adamantinomatous CP is one of the most frequently encountered central nervous system tumors in childhood. Our aim was to review the relevant literature to identify clinical, morphological, and immunohistochemical prognostic factors that have been implicated in childhood-onset CP recurrence. Lack of radical surgical removal of the primary tumor by an experienced neurosurgical team and radiotherapy after a subtotal excision has been proven to significantly increase the recurrence rate of CP. Other risk factors that have been consistently recognized in the literature include younger age at diagnosis (especially <5 years), larger tumor size at presentation, cystic appearance, difficult tumor location, and tight adherence to surrounding structures, as well as the histological presence of whorl-like arrays. In addition, several other risk factors have been studied, albeit with conflicting results, especially in the pediatric population. Identifying risk factors for CP recurrence is of utmost importance for the successful management of these patients in order to ultimately ensure the best prognosis.

Proposed System for Selection of Surgical Approaches for Craniopharyngiomas Based on the Optic Recess Displacement Pattern

OBJECTIVE

Craniopharyngiomas remain surgically challenging because of the strong adhesion to vital neurovascular structures. We propose a system for the selection of surgical approaches based on the optic recess (OR) displacement pattern to facilitate surgical planning and obtain optimum visual and endocrinologic outcomes.

METHODS

Craniopharyngiomas were divided into 3 types based on the OR displacement pattern: superior, anterior, and involvement types. Selected surgical approaches and patient outcome were retrospectively reviewed according to these classifications. Visual and endocrinologic outcomes were compared among the groups.

RESULTS

This study included 26 patients with primary craniopharyngiomas who underwent surgery at our institution, classified into 11 anterior, 11 superior, and 4 involvement types. The extended endoscopic endonasal approach provided excellent exposure inferodorsal aspect of the chiasm for manipulation of the dissection plane in the anterior and superior types with midline location. A unilateral subfrontal approach was required for tumor of the superior type with lateral extension. An interhemispheric translamina terminalis approach could provide safe dissection under direct vision of strong adhesion at the superior aspect of the chiasm in the involvement type. Visual and endocrinologic outcomes were better in the involvement type compared with the superior and anterior types. Visual outcome was significantly correlated with preoperative visual function.

CONCLUSIONS

Craniopharyngiomas with the involvement type are indicated for the translamina terminalis approach to achieve the best visual and endocrinologic outcome. Our classification of the OR displacement pattern is useful to select the optimal surgical approach for craniopharyngiomas more accurately and concisely, especially in cases with third ventricular extension.

Expression of Insulin-Like Growth Factor Type 1 Receptor Is Linked to Inflammation in Adamantinomatous Craniopharyngioma

INTRODUCTION

Insulin-like growth factor type 1 receptor (IGF1R) is overexpressed in various malignant tumors, which relates to their transformation and recurrence. Craniopharyngioma is a benign tumor with malignant results, often accompanied by a severe inflammatory reaction. However, the relationship between IGF1R expression and the inflammatory response of craniopharyngioma is unclear.

METHODS

We enrolled 85 patients with adamantinomatous craniopharyngioma (ACP) in a study to explore the relationship between IGF1R expression and clinical features of this disease.

RESULTS

Patients in the IGF1R high-expression group had a significantly higher incidence of hypopituitarism, higher recurrence rate, and lower progression-free survival. β-Catenin can further regulate expression of the stem cell marker, CD44, by regulating IGF1R. Using immunofluorescence, we found that tumor stem cell-like cells did not express phosphorylated (p)-ERK, although p-ERK activation was evident in the surrounding cells. Picropodophyllin, a specific inhibitor of IGF1R, increased the expression of p-ERK protein and decreased the transcription level of interleukin-6.

CONCLUSIONS

High expression of IGF1R might promote inflammation of ACP, which might be an unfavorable factor for pituitary function and prognosis. The high expression of IGF1R in tumor stem cell-like cells might inhibit the expression of p-ERK and promote the generation of inflammatory factors. IGF1R plays a stemness maintenance role in ACP and regulates the production of inflammatory factors through a p-ERK pathway, which suggests that targeting IGF1R and p-ERK might provide a new direction for alleviating tumor inflammation.

Reinvestigating Tumor-Ventricle Relationship of Craniopharyngiomas With Predominantly Ventricular Involvement: An Endoscopic Endonasal Series Based on Histopathological Assessment

Objective

Craniopharyngiomas (CPs) predominantly involving the third ventricle were commonly termed “intraventricular” lesions. The aim of this study was to clarify the anatomical relationship between the tumor and the third ventricle by both surgical and histological investigation.

Methods

A retrospective review of primarily resected CPs by endoscopic endonasal surgery was performed. CPs with predominantly ventricular involvement were selected for study inclusion by preoperative imaging. The surgical procedure of each case was reviewed. The wholly removed tumor specimens were histologically analyzed, in all cases, to investigate the tumor–third ventricle relationship using hematoxylin and eosin, immunochemical, and immunofluorescence staining.

Results

Twenty-six primary CPs predominantly involving the third ventricle were selected from our series of 223 CPs treated by endoscopic endonasal surgery between January 2017 and March 2021. Gross-total resection was achieved in 24 (92.3%) of 26 patients, with achievement of near-total resection in the remaining patients. A circumferential layer of stretched third ventricle floor was identified surrounding the tumor capsule, which could be peeled off easily from the ventricle floor remnants at most areas of the plane of tumor attachment. Some portions of the tumor capsule tightly adhered to the third ventricle floor were removed together with the floor. A breach of various size was observed at the third ventricle floor after tumor removal in most cases, the floor remaining intact in only two cases (7.7%). Histological examination on marked portions of tumor capsule showed that the pia mater was frequently detected at most of the tumor–brain interface, except at the antero-frontal border of tumor contacting with the third ventricle floor. At this point, a layer of gliosis with various thickness was observed between the tumor and the neural tissue of the third ventricle floor.

Conclusion

CPs with predominantly ventricular involvement should be considered as lesions with an extraventricular, epi-pia topography rather than “intraventricular” or “subpial” topography. Accurate understanding of the relationship between the third ventricle and such tumors would predict the circumferential cleavage plane of dissection, and remind neurosurgeons of performing dissection along the safe surgical plane to achieve total tumoral resection with minimizing hypothalamic damage.

Endoscopic endonasal versus transcranial surgery for primary resection of craniopharyngiomas based on a new QST classification system: a comparative series of 315 patients

OBJECTIVE

An assessment of the transcranial approach (TCA) and the endoscopic endonasal approach (EEA) for craniopharyngiomas (CPs) according to tumor types has not been reported. The aim of this study was to evaluate both surgical approaches for different types of CPs.

METHODS

A retrospective review of primary resected CPs was performed. A QST classification system based on tumor origin was used to classify tumors into 3 types as follows: infrasellar/subdiaphragmatic CPs (Q-CPs), subarachnoidal CPs (S-CPs), and pars tuberalis CPs (T-CPs). Within each tumor type, patients were further arranged into two groups: those treated via the TCA and those treated via the EEA. Patient and tumor characteristics, surgical outcomes, and postoperative complications were obtained. All variables were statistically analyzed between surgical groups for each tumor type.

RESULTS

A total of 315 patients were included in this series, of whom 87 were identified with Q-CPs (49 treated via TCA and 38 via EEA); 56 with S-CPs (36 treated via TCA and 20 via EEA); and 172 with T-CPs (105 treated via TCA and 67 via EEA). Patient and tumor characteristics were equivalent between both surgical groups in each tumor type. The overall gross-total resection rate (90.5% TCA vs 91.2% EEA, p = 0.85) and recurrence rate (8.9% TCA vs 6.4% EEA, p = 0.35) were similar between surgical groups. The EEA group had a greater chance of visual improvement (61.6% vs 35.8%, p = 0.01) and a decreased risk of visual deterioration (1.6% vs 11.0%, p < 0.001). Of the patients with T-CPs, postoperative hypothalamic status was better in the TCA group than in the EEA group (p = 0.016). Postoperative CSF leaks and nasal complication rates occurred more frequently in the EEA group (12.0% vs 0.5%, and 9.6% vs 0.5%; both p < 0.001). For Q-CPs, EEA was associated with an increased gross-total resection rate (97.4% vs 85.7%, p = 0.017), decreased recurrence rate (2.6% vs 12.2%, p = 0.001), and lower new hypopituitarism rate (28.9% vs 57.1%, p = 0.008). The recurrence-free survival in patients with Q-CPs was also significantly different between surgical groups (log-rank test, p = 0.037). The EEA required longer surgical time for T-CPs (p = 0.01).

CONCLUSIONS

CPs could be effectively treated by radical surgery with favorable results. Both TCA and EEA have their advantages and limitations when used to manage different types of tumors. Individualized surgical strategies based on tumor growth patterns are mandatory to achieve optimal outcomes.

Clinical impact of craniopharyngioma classification based on location origin: a multicenter retrospective study

Background

An assessment of the clinical impact for craniopharyngiomas (CPs) classification based on origin location has not been reported. The aim of this study was to determine the clinical impact of the site of tumor origin in primary CPs.

Methods

Patients from six national institutions who had undergone resection for primary CP were enrolled. Based on the point of origin and surrounding membranous structures, the location of the tumor origin was labelled as Q, S, or T, where Type Q CPs originated below the diaphragmatic area; Type S CPs originated from Rathke’s pouch precursor cells; and Type T CPs originated from the Rathke’s pouch precursor cells located above the pars tuberalis. Clinical characteristics, surgical approach, and outcome were evaluated according to the location of the tumor origin.

Results

Among the 529 patients with primary CP, symptoms, age, histopathology type, tumor size, the incidence of hydrocephalus, survival rates, and recurrence-free survival rates were significantly different among tumors originating in different locations. Patients with type T CPs had higher symptom rates of intracranial hypertension and hypothalamic dysfunction, while those with type Q CPs had higher rates of hormone deficits during pre-and post-operative management. Type S CPs were correlated with better outcomes and lower recurrence rates. The location of origin and primary therapy with survival and recurrence in CP were independent factors for survival and recurrence in multivariate analysis.

Conclusions

The identification of the different location of origin of CPs is of great significance in understanding the relationship between tumors and peripheral tissues. The origin of tumors effects the choice of surgical approach and prognosis.

An endoscopic endonasal approach to craniopharyngioma via the infrachiasmatic corridor: a single center experience of 84 patients

OBJECT

The infrachiasmatic corridor is the most important surgical access route for craniopharyngiomas and was identified and used in clinical series. The aims of this study were to describe the characteristics that assist dissection and resection rates in endoscopic surgery of solid, cystic, and recurrent cases and their importance in the infrachiasmatic corridor in endoscopic surgery.

METHODS

One hundred operations on 84 patients with pathologically identified craniopharyngioma were included in the study. The MRI findings were evaluated, and the location of the lesions was classified as (1) infrasellar; (2) sellar; or (3) suprasellar. In the sagittal plane, we measured the longest diameter of cystic and solid components and the height of chiasm-sella. Images were assessed for the extent of resection and were classified as gross total resection. This was deemed as the absence of residual tumor and subtotal resection, which had residual tumor.

RESULTS

The infrasellar location was reported in 7/84 (8.3%) patients, the sellar location in 8/84 (9.5%), and the suprasellar location in 69/84 (82.1%) patients. The narrow and high chiasm-sella were observed in 28/69 (40.5%) and 41/69 patients (59.4%), respectively. The mean distance of the chiasm-sella was 9.46± 3.76. Gross total tumor resection was achieved in 60/84 (71.4%) and subtotal tumor resection was performed in 24/84 (28.6%) patients. The results revealed that suprasellar location (OR: 0.068; p = 0.017) and recurrent cases (OR: 0.011; p<0.001) were negative predictive factors on GTR. Increasing the experience (OR: 42,504; p = 0.001) was a positive predictor factor for GTR.

CONCLUSION

An EETS approach that uses the infrachiasmatic corridor is required for skull base lesions extending into the suprasellar area. The infrachiasmatic corridor can determine the limitations of endoscopic craniopharyngioma surgery. This corridor is a surgical safety zone for inferior approaches.

Surgical Anatomy Applied to the Resection of Craniopharyngiomas: Anatomic Compartments and Surgical Classifications

BACKGROUND

Resective surgery remains the main treatment option for most patients with craniopharyngiomas. Understanding of the microsurgical anatomy of the sella and suprasellar region and its relationship with these tumors is necessary to achieve effective surgical treatment and minimize complications. In this article, we review the surgical anatomy related to craniopharyngiomas and divide it in 5 compartments according to tumor extension.

METHODS

Endoscopic and microsurgical dissection were performed in 3 freshly injected cadaver heads at the Weill Cornell Surgical Innovations Laboratory (New York, New York, USA) and at the Surgical Skills Center at Mount Sinai Hospital (Toronto, Ontario, Canada). Tumor extension was classified as 1) inferomedial or sellar, 2) superomedial or suprasellar, 3) lateral or sylvian, 4) posterior or interpeduncular/prepontine, and 5) intraventricular. The selection of surgical approaches is discussed based on the anatomic nuances of each these regions. In addition, we reviewed the literature regarding previous anatomic classifications for resection of craniopharyngiomas.

RESULTS

Different approaches should be considered according to tumor extension into different compartments. Purely sellar tumors are amenable to endoscopic transsellar approaches, whereas those with a suprasellar extension require an extended transtuberculum approach. In some of those patients, a narrow chiasm-pituitary window may block access to the tumor and a transcranial translamina terminalis approach may be favored. Tumors occupying the interpeduncular fossa may pose a significant challenge for an endoscopic endonasal approach and transcranial approaches. Transcavernous approaches and anterior and posterior clinoidectomies may be required for adequate exposure in such patients. Translamina terminalis and/or transcallosal approaches are recommended for resection of purely intraventricular tumors. Tumors extending into the lateral compartment should be considered for transcranial frontotemporal approaches.

CONCLUSIONS

The understanding of such anatomic nuances aids in the selection of the most appropriate surgical approach and in the prevention of potential complications. Because most craniopharyngiomas are midline lesions, the endoscopic endonasal approach represents an excellent approach for most of those tumors. However, transcranial approaches should be considered for tumors with extension into the lateral compartment and for selected tumors involving the ventricular compartment (purely intraventricular tumors and those with extension to the foramen of Monro and/or lateral ventricles).

Membrane Structures Between Craniopharyngioma and the Third Ventricle Floor Based on the QST Classification and Its Significance: A Pathological Study

The aim of this study was to clarify the relationship between craniopharyngiomas (CP) and the third ventricle floor by analyzing the membranes between them. Eight fetal specimens were first examined by hematoxylin and eosin and immunofluorescence staining to determine optimal markers for identifying membrane structures in the sellar region. Then, 17 CP with third ventricle floor involvement that had been removed by total en bloc resection through a transsphenoidal approach were examined. We found that the dura mater, arachnoid membrane, and pia mater could be seen to separate type Q tumors from the third ventricle floor. The arachnoid membrane and pia mater could be seen between type S tumors and the third ventricle floor. Pia mater could be seen between type T tumors and the third ventricle floor; however, at the origin point of the tumor, pia mater could be loosened or replaced by the tumor. Although some type T tumors compressed the third ventricle, the ependymal layer remained intact. Based on these embryonic and pathological data, we suggest that CP are nonneuroepithelial, epi-pia mater, and epi-third ventricle tumors.

Craniopharyngiomas primarily affecting the hypothalamus

The concept of craniopharyngiomas (CPs) primarily affecting the hypothalamus, or "hypothalamic CPs" (Hy-CPs), refers, in a restrictive sense, to the subgroup of CPs originally developing within the neural tissue of the infundibulum and tuber cinereum, the components of the third ventricle floor. This subgroup, also known as infundibulo-tuberal CPs, largely occupies the third ventricle and comprises up to 40% of this pathological entity. The small subgroup of strictly intraventricular CPs (5%), lesions wholly developed within the third ventricle above an anatomically intact third ventricle floor, can also be included within the Hy-CP category. The remaining types of sellar and/or suprasellar CPs may compress or invade the hypothalamic region during their growth but will not be considered in this review. Hy-CPs predominantly affect adults, causing a wide range of symptoms derived from hypothalamic dysfunction, such as adiposogenital dystrophy (Babinski-Fröhlich's syndrome), diabetes insipidus (DI), abnormal diurnal somnolence, and a complex set of cognitive (dementia-like, Korsakoff-like), emotional (rage, apathy, depression), and behavioral (autism-like, psychotic-like) disturbances. Accordingly, Hy-CPs represent a neurobiological model of psychiatric disorders caused by a lesion restricted to the hypothalamus. The vast majority (90%) of squamous-papillary CPs belong to the Hy-CP category. Pathologically, most Hy-CPs present extensive and strong adhesions to the surrounding hypothalamus, usually formed of a thick band of gliotic tissue encircling the central portion of the tumor ("ring-like" attachment) or its entire boundary ("circumferential" attachment). CPs with these severe adhesion types associate high surgical risk, with morbidity and mortality rates three times higher than those for sellar/suprasellar CPs. Consequently, radical surgical removal of Hy-CPs cannot be generally recommended. Rather, Hy-CPs should be accurately classified according to an individualized surgery-risk stratification scheme considering patient age, CP topography, presence of hypothalamic symptoms, tumor size, and, most importantly, the CP-hypothalamus adhesion pattern.

Hypothalamic injury patterns after resection of craniopharyngiomas and correlation to tumor origin: A study based on endoscopic observation

The precise understanding of hypothalamic injury (HI) patterns and their relationship with different craniopharyngioma (CP) classifications remains poorly addressed. Here, four HI patterns after CP resection based on endoscopic observation were introduced. A total of 131 CP cases treated with endoscopic endonasal approach (EEA) were reviewed retrospectively and divided into four HI patterns: no-HI, mild-HI, unilateral-HI and bilateral-HI, according to intraoperative findings. The outcomes were evaluated and compared between groups in terms of weight gain, endocrine status, electrolyte disturbance and neuropsychological function before and after surgery. A systematic correlation was found between CP origin and subsequent HI patterns. The majority of intrasellar and suprasellar stalk origins lead to a no-HI pattern, the central-type CP mainly develops a mild or bilateral HI pattern, and the majority of tumors with hypothalamic stalk origins result in unilateral HI and sometimes bilateral HI patterns. The proportion of tumors with a maximum diameter >3 cm in the no-HI group was higher than that in the mild-HI group, BMI and quality of life in the no-HI group showed better results than those in the other groups. The incidence of new-onset diabetes insipidus in the bilateral-HI group was significantly higher than that in the other groups. Memory difficulty was observed mainly in the unilateral-HI and bilateral-HI groups. However, the outcomes of electrolyte disturbance, sleep, and cognitive disorder in the unilateral-HI group were significantly better than those in the bilateral-HI group. This study suggests the possibility of using pre- and intraoperative observation of CP origin to predict four HI patterns and even subsequent outcomes after tumor removal.

Craniopharyngioma treatment: an updated summary of important clinicopathological concepts

INTRODUCTION

Craniopharyngiomas (CPs) are benign histological tumors that may develop at different positions along the hypothalamic-pituitary axis. Their close, heterogenous relationship to the hypothalamus makes surgical removal challenging even though this remains the primary treatment strategy.

AREAS COVERED

This article presents a critical overview of the pathological and clinical concepts regarding CPs that should be considered when planning treatment. Thus, we have performed a comprehensive review of detailed CP reports published between 1839 and 2020.

EXPERT OPINION

CP surgery should pursue maximal tumor resection while minimizing the risk of injuring the hypothalamus. Therefore, surgical strategies should be individualized for each patient. Accurate assessment of presenting symptoms and preoperative MRI has proven useful to predict the type of CP-hypothalamus relationship that will be found during surgery. CPs with dense and extensive adhesions to the hypothalamus should be highly suspected when MRI shows the hypothalamus positioned around the mid-third of the tumor and an amputated upper portion of the pituitary stalk. Symptoms related to functional impairment of the infundibulo-tuberal area of the third ventricle floor, such as obesity/hyperphagia, Fröhlich's syndrome, diabetes insipidus, and/or somnolence, also indicate risky CP-hypothalamic adhesions. In these cases, limited tumor removal is strongly advocated followed by radiation therapy.

Development of a novel score to predict probability of growth without growth hormone after resection of paediatric craniopharyngiomas: relative to tumour growth pattern

OBJECTIVE

Some patients with paediatric craniopharyngiomas (PCs) showed normal growth despite growth hormone deficiency, which is known as growth without GH (GWGH); however, its mechanism remains unclear. We aimed to develop a novel clinical score to predict the probability of GWGH in PCs.

METHODS

A total of 708 PC patients were prospectively enrolled from six hospitals, among which 431 patients were finally included. Data from four of the six hospitals (n = 325) were used to develop the innovative clinical score (ICS), which was further validated using the data from the other two hospitals (n = 106). To establish and validate the ICS, sequential logistic regression was used to analyse the clinical characteristics including tumour growth pattern and tumour size and so on. Furthermore, C-statistic was employed to calibrate the discriminatory ability of the established clinical score, while a calibration plot was adopted for further assessment.

RESULTS

The overall incidence of GWGH was 16.9% (73/431). The ICS ranged from 2 to 23, with an optimism-corrected C-statistic of 0.820, Furthermore, the optimism-corrected C-statistic of external validation was 0.835, indicating good discriminatory power and robustness of the clinical score. Additionally, no apparent overestimation or underestimation was observed in the calibration plots, which showed excellent calibration power of the clinical score.

CONCLUSIONS

Based on tumour growth patterns and PC patients' clinical characteristics, individualized surgical strategies were promising to achieve long-term effective management of PC patients. The ICS is valuable for the evaluation of probability of developing postoperative GWGH.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT00949156.

Surgical management of craniopharyngiomas in adult patients: a systematic review and consensus statement on behalf of the EANS skull base section

BACKGROUND AND OBJECTIVE

Craniopharyngiomas are locally aggressive neuroepithelial tumors infiltrating nearby critical neurovascular structures. The majority of published surgical series deal with childhood-onset craniopharyngiomas, while the optimal surgical management for adult-onset tumors remains unclear. The aim of this paper is to summarize the main principles defining the surgical strategy for the management of craniopharyngiomas in adult patients through an extensive systematic literature review in order to formulate a series of recommendations.

MATERIAL AND METHODS

The MEDLINE database was systematically reviewed (January 1970-February 2019) to identify pertinent articles dealing with the surgical management of adult-onset craniopharyngiomas. A summary of literature evidence was proposed after discussion within the EANS skull base section.

RESULTS

The EANS task force formulated 13 recommendations and 4 suggestions. Treatment of these patients should be performed in tertiary referral centers. The endonasal approach is presently recommended for midline craniopharyngiomas because of the improved GTR and superior endocrinological and visual outcomes. The rate of CSF leak has strongly diminished with the use of the multilayer reconstruction technique. Transcranial approaches are recommended for tumors presenting lateral extensions or purely intraventricular. Independent of the technique, a maximal but hypothalamic-sparing resection should be performed to limit the occurrence of postoperative hypothalamic syndromes and metabolic complications. Similar principles should also be applied for tumor recurrences. Radiotherapy or intracystic agents are alternative treatments when no further surgery is possible. A multidisciplinary long-term follow-up is necessary.

Surgical Outcomes and Predictors of Visual Function Alterations After Transcranial Surgery for Large-to-Giant Pituitary Adenomas

BACKGROUND

Factors associated with visual outcomes after transcranial surgery for large-to-giant pituitary adenomas have not been fully elucidated.

METHODS

We recruited 37 patients with large-to-giant pituitary adenomas between January 2014 and December 2016 and assessed their tumor characteristics and surgical outcomes. Visual acuity and visual field were evaluated by visual impairment score before and 3-6 months after transcranial surgery. Multivariable logistic regression analysis was applied to show the factors associated with visual outcomes after surgery.

RESULTS

The severity levels of visual impairment before surgery were mild, moderate, severe, and complete in 24.3% (9/37), 24.3% (9/37), 35.1% (13/37), and 16.2% (6/37), respectively. After surgery, the visual function was improved, stabilized, and worsened in 43.2% (16/37), 43.2% (16/37), and 13.5% (5/37) of patients, respectively. Multivariable logistic regression analysis showed that subarachnoid space invasion was the only independent prognostic factor adversely influencing the postoperative visual outcomes. Patients with subarachnoid space invasion had a higher possibility of visual deterioration (36.4% vs. 3.8%; P = 0.021) after transcranial surgery, compared with those without subarachnoid space invasion.

CONCLUSIONS

Visual compromise is still an unignorable complication during transcranial surgery for large-to-giant pituitary adenomas. Subarachnoid space invasion indicated by preoperative magnetic resonance imaging was an independent negative predictor for visual outcomes after surgery.

A retaining sphenoid and dura procedure in the rat to obtain intact pituitary-infundibulum-hypothalamus preparations

BACKGROUND

The histopathological study of brain tissue is a conventional method in neuroscience. However, procedures specifically developed to recover intact hypothalamic-pituitary brain specimens, are not available.

NEW METHOD

We describe a detailed protocol for obtaining intact rat brain with pituitary-hypothalamus continuity through an intact infundibulum. The brain is collected via a ventral approach through removing the skull base. Membranous structures surrounding the hypothalamus-pituitary system can be preserved, including vasculature.

RESULTS

We report a retaining sphenoid and dura technique to obtain intact hypothalamic-pituitary brain preparations, and we confirm the practicability of this method. By combination of this technique with histological analysis or 3D brain tissue clearing and imaging methods, the functional morphology structure of the hypothalamus-pituitary can be further explored.

COMPARISON WITH EXISTING METHOD

The current procedure is limited in showing the connection between the hypothalamus and the pituitary. Our procedure effectively protects the integrity of the fragile infundibulum and thus prevents the pituitary from separating from the hypothalamus.

CONCLUSIONS

We present a convenient and practical approach to obtain intact hypothalamus-pituitary brain specimens for subsequent histopathological evaluation.

Preserve or sacrifice the stalk? Endocrinological outcomes, extent of resection, and recurrence rates following endoscopic endonasal resection of craniopharyngiomas

OBJECTIVE

Gross-total resection (GTR) of craniopharyngiomas (CPs) is potentially curative and is often the goal of surgery, but endocrinopathy generally results if the stalk is sacrificed. In some cases, GTR can be attempted while still preserving the stalk; however, stalk manipulation or devascularization may cause endocrinopathy and this strategy risks leaving behind small tumor remnants that can recur.

METHODS

A retrospective review of a prospective cohort of patients who underwent initial resection of CP using the endoscopic endonasal approach over a period of 12 years at Weill Cornell Medical College, NewYork-Presbyterian Hospital, was performed. Postresection integrity of the stalk was retrospectively assessed using operative notes, videos, and postoperative MRI. Tumors were classified based on location into type I (sellar), type II (sellar-suprasellar), and type III (purely suprasellar). Pre- and postoperative endocrine function, tumor location, body mass index, rate of GTR, radiation therapy, and complications were reviewed.

RESULTS

A total of 54 patients who had undergone endoscopic endonasal procedures for first-time resection of CP were identified. The stalk was preserved in 33 (61%) and sacrificed in 21 (39%) patients. GTR was achieved in 24 patients (73%) with stalk preservation and 21 patients (100%) with stalk sacrifice (p = 0.007). Stalk-preservation surgery achieved GTR and maintained completely normal pituitary function in only 4 (12%) of 33 patients. Permanent postoperative diabetes insipidus was present in 16 patients (49%) with stalk preservation and in 20 patients (95%) following stalk sacrifice (p = 0.002). In the stalk-preservation group, rates of progression and radiation were higher with intentional subtotal resection or near-total resection compared to GTR (67% vs 0%, p < 0.001, and 100% vs 12.5%, p < 0.001, respectively). However, for the subgroup of patients in whom GTR was achieved, stalk preservation did not lead to significantly higher rates of recurrence (12.5%) compared with those in whom it was sacrificed (5%, p = 0.61), and stalk preservation prevented anterior pituitary insufficiency in 33% and diabetes insipidus in 50%.

CONCLUSIONS

While the decision to preserve the stalk reduces the rate of postoperative endocrinopathy by roughly 50%, nevertheless significant dysfunction of the anterior and posterior pituitary often ensues. The decision to preserve the stalk does not guarantee preserved endocrine function and comes with a higher risk of progression and need for adjuvant therapy. Nevertheless, to reduce postoperative endocrinopathy attempts should be made to preserve the stalk if GTR can be achieved.

A modern series of subdiaphragmatic craniopharyngiomas

OBJECTIVE

The endoscopic endonasal approach has been proposed as a primary surgical strategy for select craniopharyngiomas. However, those tumors that arise from the sella have not been classified with the other craniopharyngioma subtypes in terms of surgical nuances, intraoperative findings, and postoperative outcomes. The authors describe their experience with a select subtype of craniopharyngioma arising within the sella subjacent to the diaphragma sellae and refer to these tumors as type 0.

METHODS

After obtaining IRB approval, three institutions retrospectively reviewed their data collected from 2005 to 2017. Patients eligible for inclusion in the study were those who had tumors that originated from the sella inferior to the diaphragma sellae. Demographic, clinical, radiological, surgical, and follow-up data were examined and analyzed.

RESULTS

Twenty-eight patients (average age 19.3 years, range 3-60 years) were included in this study. Sixteen patients (57%) were younger than 18 years of age. All patients had characteristic imaging features of an expanded sella. Seventy-five percent of the patients presented with some form of visual field deficit (89% had radiographic optic apparatus compression) and 39% with hypopituitarism. The average maximal tumor diameter in the axial, coronal, or sagittal plane was 3.1 cm. Gross-total resection was achieved in 82% of the patients. Twenty-one percent of patients experienced an iatrogenic complication, and there were only two cases (7%) of postoperative cerebrospinal fluid (CSF) leakage. Only two patients (7%) required the use of a nasoseptal flap as part of their original reconstruction. Pathology was uniformly the adamantinomatous subtype. Postoperative objective visual outcomes were improved in 71% of the patients with visual symptoms or visual field deficits on presentation and stable in 24%. Mean follow-up was 45.1 months (range 3-120 months) with an 18% recurrence rate at a mean of 44.4 months (range 10-84 months). One patient was lost to follow-up. Thirty-six percent of patients received postoperative radiation to treat recurrence or residual tumor. Endocrine data are also presented.

CONCLUSIONS

Craniopharyngiomas that originate within the sella below the diaphragma sellae are a select subtype characterized by 1) an enlarged sella, 2) an intact diaphragma sellae at surgery, and 3) an adamantinomatous pathology. These tumors can be treated transnasally without the absolute need for neurovascular flap reconstruction, as there is a low risk of CSF leakage.

Trans-eyebrow supraorbital keyhole approach in suprasellar and third ventricular craniopharyngioma surgery: the experience of 27 cases and a literature review

BACKGROUND

The trans-eyebrow supraorbital keyhole approach, a minimal transcranial approach, has been widely used in different types of surgery for sellar and parasellar lesions. In this study, we investigated the outcome of this approach in the surgical treatment of suprasellar and third ventricular craniopharyngioma.

METHODS

Twenty-seven patients with suprasellar and third ventricular craniopharyngioma underwent surgery via a supraorbital approach between June 2007 and June 2018. The medical data and follow-up results were retrospectively analyzed.

RESULTS

All tumors were located in the suprasellar region and the third ventricle. The mean tumor size was 29.1 mm. The mean follow-up period was 49.6 months. Gross total resection (GTR) was achieved in 23 patients (85.2%). Of 17 patients with preoperative visual impairment, 12 patients (70.6%) showed improvement. Following surgery, 11 patients exhibited new-onset anterior hypopituitarism, ten developed diabetes insipidus, and two became overweight. One residual tumor relapsed 1 year after surgery. No perioperative death, cerebrospinal fluid (CSF) rhinorrhea, or meningitis occurred. All patients exhibited satisfactory cosmetic results. At the last follow-up, the Extended Glasgow Outcome Scale Score was 8 in 25 patients (92.6%).

CONCLUSION

The supraorbital trans-eyebrow keyhole approach is characterized by minimal invasion and a satisfactory cosmetic outcome. According to our experience, craniopharyngiomas located in the suprasellar region and the third ventricle can be safely resected via a trans-eyebrow supraorbital keyhole approach.

Effects of craniopharyngioma cyst fluid on neurons and glial cells cultured from rat brain hypothalamus

Craniopharyngiomas (CPs) are rare, epithelial tumors of the central nervous system (CNS) that could lead to manifestation of multiple post-operative symptoms, ranging from hormonal imbalance to obesity, diabetes, visual, neurological and neurocognitive impairments. CP is more frequent in children, and has been reported in middle aged adults as well. In fact, arterial laceration and/or brain stroke which may occur following the removal of some CPs is mainly due to calcification of that CPs along with strong attachments to the blood vessels. The dense oily fluid content of CPs is reported to cause brain tissue damage, demyelination and axonal loss in the hypothalamus; however, its exact effect on different cell types of CNS is still unexplored. In this study, we have collected CP cyst fluid (CCF) from mostly young patients during surgical removal and exposed it 9-10 days in vitro to the primary cultures derived from rat brain hypothalamus for 48 h. A gradual decline in cell viability was noted with increasing concentration of CCF. Moreover, a distinct degenerative morphological transformation was observed in neurons and glial cells, including appearance of blebbing and overall reduction of the cell volume. Further, enhanced expression of Caspase-3 in neurons and glial cells exposed to CCF by immunofluorescence imaging, supported by Western blot experiment suggest CCF induced apoptosis of hypothalamic cells in culture. In this study, we have demonstrated the deleterious effects of the cyst fluid on various cell types within the tumors originating region of the brain and its surroundings for the first time. Taken together, this finding could be beneficial towards identifying the region specific toxic effects of the cyst fluid and its underlying mechanism.

A novel endoscopic classification for craniopharyngioma based on its origin

Endoscopic endonasal approach for craniopharyngioma (CP) resection provides a wide view and direct observation of hypothalamus and origin of tumor. Under endoscopy, 92 CPs were classified into 2 types: Peripheral and Central, according to its relation to pituitary stalk. Peripheral type was further divided into 3 subtypes: Hypothalamic stalk, Suprasellar stalk and Intrasellar stalk CP, according to the different origin site along hypothalamus-pituitary axis. Peripheral type arisen from the stalk but expanded and grown laterally in an exophytic pattern, accounting for 71.7% of all CPs, preservation rate of stalk was higher (76.0%). Central type grew within and along pituitary stalk and located strictly in the midline. The pituitary stalk was hardly preserved (only15.4%). Hypothalamic stalk CPs (n = 36, 54.6%) developed from the junction of hypothalamus and stalk, hypothalamus damage was found in all of this subtype after surgery. Suprasellar stalk CPs (n = 14, 21.2%) originated from the lower portion of stalk and displaced hypothalamus upward rather than infiltrated it. Intrasellar stalk CPs (n = 16, 24.2%) arose from the subdiaphragma portion of the stalk, with less hypothalamus damage. Recoginzing the origin of CP is helpful to understand its growth pattern and relation to hypothalamus, which is critical in planning the most appropriate surgical approach and degree of excision.

Risk score for the prediction of severe obesity in pediatric craniopharyngiomas: relative to tumor origin

BackgroundWe aimed to develop a risk score to improve the prediction of severe obesity in pediatric craniopharyngiomas (PCs).MethodsOverall, 612 consecutive PCs were prospectively enrolled from six hospitals. Data from 404 participants were analyzed. Participants from three of the six hospitals (n=290) were used to develop a risk score. External validation of the developed risk score was conducted using the participants from the other three hospitals (n=114). Sequential logistic regression was used to develop and validate the risk score. The c statistic and a calibration plot were used to assess the discrimination and calibration of the proposed risk score.ResultsThe overall frequency of severe obesity was 16.1% (65/404). The risk score employed a scale of 0-16 and demonstrated good discriminative power, with an optimism-corrected c statistic of 0.820. Similar results were obtained from external validation, with a c statistic of 0.821. The risk score showed good calibration, with no apparent over- or under-prediction observed in the calibration plots.ConclusionsThis novel risk score is a simple tool that can help clinicians assess the risk of severe obesity in PCs, thereby helping to plan and initiate the most appropriate disease management for these patients in time.

Preoperative Assessment of Craniopharyngioma Adherence: Magnetic Resonance Imaging Findings Correlated with the Severity of Tumor Attachment to the Hypothalamus

BACKGROUND AND OBJECTIVE

Craniopharyngioma (CP) adherence represents a heterogeneous pathologic feature that critically influences the potentially safe and radical resection. The aim of this study was to define the magnetic resonance imaging (MRI) predictors of CP adherence severity.

METHODS

This study retrospectively investigated a cohort of 200 surgically treated CPs with their corresponding preoperative conventional MRI scans. MRI findings related to the distortions of anatomic structures along the sella turcica-third ventricle axis caused by CPs, in addition to the tumor's shape and calcifications, were analyzed and correlated with the definitive type of CP adherence observed during the surgical procedures.

RESULTS

CP adherence is defined by 3 components, as follows: 1) the specific structures attached to the tumor, 2) the adhesion's extent, and 3) its strength. Combination of these 3 components determines 5 hierarchical levels of adherence severity with gradually increasing surgical risk of hypothalamic injury. Multivariate analysis identified 4 radiologic variables that allowed a correct overall prediction of the levels of CP adherence severity in 81.5% of cases: 1) the position of the hypothalamus in relation to the tumor-the most discriminant factor; 2) the type of pituitary stalk distortion; 3) the tumor shape; and 4) the presence of calcifications. A binary logistic regression model including the first 3 radiologic variables correctly identified the CPs showing the highest level of adherence severity (severe/critical) in almost 90% of cases.

CONCLUSIONS

A position of the hypothalamus around the middle portion of the tumor, an amputated or infiltrated appearance of the pituitary stalk, and the elliptical shape of the tumor are reliable predictors of strong and extensive CP adhesions to the hypothalamus.

Endoscopic endonasal approach for craniopharyngioma: the importance of the relationship between pituitary stalk and tumor

OBJECTIVE The endoscopic endonasal approach (EEA) is commonly used for the treatment of craniopharyngioma; therefore, it is essential to analyze outcomes in order to understand the benefits and drawbacks. The goal of this paper was to evaluate the clinical features and outcomes associated with this treatment approach. METHODS From July 2010 to March 2016, 82 adult craniopharyngioma patients underwent an EEA at the authors' institution. Of these cases, intraoperative records and immediate postoperative MR images were available for 68 patients. The patients underwent systemized endocrinological evaluation. Eighteen of 68 patients who underwent EEA for recurrence or regrowth of residual lesions after previous surgical management were excluded in the analysis of the anatomical tumor classification. The authors retrospectively analyzed preoperative clinical features and previous anatomical classifications, focusing on the relationship of the pituitary stalk and tumor, to determine predictive factors for the clinical outcome, such as the extent of resection, visual function, endocrinological function, recurrence rate, and complications. RESULTS The mean tumor size was 2.5 cm (3.1 cm for primary tumors and 1.9 cm for recurrent lesions). Gross-total resection (GTR) was achieved in 62 (91.1%) patients (48 [96.0%] patients with primary tumors and 14 [77.8%] patients with recurrent tumors). The rate of GTR was higher in the primary group than in the group with recurrence (p = 0.038). The overall pre- and postoperative visual impairment scale (VIS) scores were 40.8 and 22.1, respectively (50.9 and 14.3 in the primary group and 30.7 and 29.9 in patients with recurrence, respectively). The improvement rate in VIS score was higher in the primary group than in the recurrent group (p = 0.001). Endocrinological function was improved in 4 patients (5.9%) and deteriorated in 32 of 68 patients (47.1%). Tumor invasion into the center of the pituitary stalk affected the postoperative outcomes most significantly. Cognitive dysfunction was observed in 22 patients before surgery and improved in 20 patients (90.9%) after surgery. Hydrocephalus was found in 7 patients and resolved after surgery in all cases. CSF leakage occurred in 2 (2.9%) of 68 patients and was repaired by revision surgery in both patients. Ten patients without CSF leakage also received antibiotics for the treatment of meningitis. The infection rate was higher in the recurrent group. Postoperative endocrinological evaluation showed no deficits in 12 patients and panhypopituitarism in 55 patients. The remaining patient had growth hormone deficiency. Forty-three patients had new-onset diabetes insipidus, and 1 patient had persistent diabetes insipidus after surgery. There were 2 (2.9%) cases of recurrence during the mean 30.7-month follow-up period; one patient underwent radiosurgery and the other underwent reoperation. CONCLUSIONS The EEA resulted in excellent surgical outcomes and acceptable morbidity rates, regardless of the anatomical location of the tumor. Invasion of the craniopharyngioma into the center of the pituitary stalk has strong predictive power for postoperative endocrinological outcome.

New outlook on the diagnosis, treatment and follow-up of childhood-onset craniopharyngioma

Childhood-onset craniopharyngiomas are rare embryonic tumours of low-grade histological malignancy. Novel insights into the molecular pathogenesis of human adamantinomatous craniopharyngioma have started to unveil the possibility of testing novel treatments targeting pathogenic pathways. Hypothalamic involvement and/or treatment-related lesions result in impaired physical and social functionality and in severe neuroendocrine sequelae. Quality of survival in patients with craniopharyngioma with hypothalamic involvement is impaired by severe obesity, physical fatigue and non-optimal psychosocial development. Patients with craniopharyngioma involving hypothalamic structures have reduced 20-year overall survival, but overall and progression-free survival are not related to the degree of surgical resection. Irradiation is effective in the prevention of tumour progression and recurrence. For favourably localized craniopharyngiomas, the preferred treatment of choice is to attempt complete resection with preservation of visual, hypothalamic and pituitary function. For unfavourably localized tumours in close proximity to optic and/or hypothalamic structures, a radical neurosurgical strategy attempting complete resection is not recommended owing to potential severe sequelae. As expertise has been shown to have an impact on post-treatment morbidity, medical societies should establish criteria for adequate professional expertise for the treatment of craniopharyngioma. On the basis of these criteria, health authorities should organize the certification of centres of excellence that are authorized to treat and care for patients with this chronic disease.

Craniopharyngioma adherence: a comprehensive topographical categorization and outcome-related risk stratification model based on the methodical examination of 500 tumors

OBJECTIVE Craniopharyngioma (CP) adherence strongly influences the potential for achieving a radical and safe surgical treatment. However, this factor remains poorly addressed in the scientific literature. This study provides a rational, comprehensive description of CP adherence that can be used for the prediction of surgical risks associated with the removal of these challenging lesions. METHODS This study retrospectively analyzes the evidence provided in pathological, neuroradiological, and surgical CP reports concerning 3 components of the CP attachment: 1) the intracranial structures attached to the tumor; 2) the morphology of the adhesion; and 3) the adhesion strength. From a total of 1781 CP reports published between 1857 and 2016, a collection of 500 CPs providing the best information about the type of CP attachment were investigated. This cohort includes autopsy studies (n = 254); surgical studies with a detailed description or pictorial evidence of CP adherence (n = 298); and surgical CP videos (n = 61) showing the technical steps for releasing the attachment. A predictive model of CP adherence in hierarchical severity levels correlated with surgical outcomes was generated by multivariate analysis. RESULTS The anatomical location of the CP attachment occurred predominantly at the third ventricle floor (TVF) (54%, n = 268), third ventricle walls (23%, n = 114), and pituitary stalk (19%, n = 94). The optic chiasm was involved in 56% (n = 281). Six morphological patterns of CP attachment were identified: 1) fibrovascular pedicle (5.4%); 2) sessile or patch-like (21%); 3) cap-like (over the CP top, 14%); 4) bowl-like (around the CP bottom, 13.5%); 5) ring-like (encircling central band, 19%); and 6) circumferential (enveloping the entire CP, 27%). Adhesion strength was classified in 4 grades: 1) loose (easily dissectible, 8%); 2) tight (requires sharp dissection, 32%); 3) fusion (no clear cleavage plane, 40%); and 4) replacement (loss of brain tissue integrity, 20%). The types of CP attachment associated with the worst surgical outcomes are the ring-like, bowl-like, and circumferential ones with fusion to the TVF or replacement of this structure (p < 0.001). The CP topography is the variable that best predicts the type of CP attachment (p < 0.001). Ring-like and circumferential attachments were observed for CPs invading the TVF (secondary intraventricular CPs) and CPs developing within the TVF itself (infundibulo-tuberal CPs). Brain invasion and peritumoral gliosis occurred predominantly in the ring-like and circumferential adherence patterns (p < 0.001). A multivariate model including the variables CP topography, tumor consistency, and the presence of hydrocephalus, infundibulo-tuberal syndrome, and/or hypothalamic dysfunction accurately predicts the severity of CP attachment in 87% of cases. CONCLUSIONS A comprehensive descriptive model of CP adherence in 5 hierarchical levels of increased severity-mild, moderate, serious, severe, and critical-was generated. This model, based on the location, morphology, and strength of the attachment can be used to anticipate the surgical risk of hypothalamic injury and to plan the degree of removal accordingly.

Pathological and Topographical Classification of Craniopharyngiomas: A Literature Review

Craniopharyngiomas (CPs) are clinically relevant tumors of the sellar region and are associated with high morbidity and occasional mortality. There are two different subtypes of CPs that differ clinically and pathologically: adamantinomatous CP and papillary CP. The differential diagnosis is still challenging even with developments in preoperative imaging as several tumors of the sellar/parasellar region share a continuum of clinical characteristics and imaging similarities. Several topographical classifications of CPs have been mentioned in literature, but to date, there has not been a consensus on a standard reference classification system and there is need to a develop such a model.

Epithelial-mesenchymal transition and clinicopathological correlation in craniopharyngioma

AIMS

To assess the immunophenotypic changes associated with epithelial-mesenchymal transition (EMT) in craniopharyngioma, especially at the tumour invasive front, and to correlate the findings with clinicopathological features and patient outcomes.

METHODS AND RESULTS

Forty-two craniopharyngiomas were investigated for the presence of EMT markers (vimentin, E-cadherin and β-catenin) by immunohistochemistry and western blot. The relationships between expression of these markers and various clinicopathological indicators and clinical outcomes of the tumours were analysed. There were statistically significant differences in the expression of vimentin and E-cadherin-β-catenin between adamantinomatous and papillary variants. The expression of vimentin and E-cadherin (but not that of β-catenin) in whole tumour sections was associated with tumour recurrence, and with postoperative weight and hypothalamic disturbances; the expression of vimentin and E-cadherin-β-catenin at the tumour invasive front was also associated with tumour recurrence, postoperative weight, and hypothalamic disturbances. The results from western blotting closely matched those of immunohistochemistry.

CONCLUSION

Our study demonstrates, for the first time, the potential prognostic implications of vimentin, E-cadherin and β-catenin expression in craniopharyngiomas. EMT may represent a crucial mechanism in the progression of craniopharyngiomas.

Origin of craniopharyngiomas: implications for growth pattern, clinical characteristics, and outcomes of tumor recurrence

OBJECT

Craniopharyngiomas are associated with a high rate of recurrence. The surgical management of recurrent lesions has been among the most challenging neurosurgical procedures because of the craniopharyngioma's complex topographical relationship with surrounding structures. The aim of this study was to define the determinative role of the site of origin on the growth pattern and clinical features of recurrent craniopharyngiomas.

METHODS

The authors performed a retrospective analysis of 52 patients who had undergone uniform treatment by a single surgeon. For each patient, data concerning symptoms and signs, imaging features, hypothalamic-pituitary function, and recurrence-free survival rate were collected.

RESULTS

For children, delayed puberty was more frequent in the group with Type I (infradiaphragmatic) craniopharyngioma than in the group with Type TS (tuberoinfundibular and suprasellar extraventricular) lesions (p < 0.05). For adults, blindness was more frequent in the Type I group than in the Type TS group (p < 0.05). Nausea or vomiting, delayed puberty, and growth retardation were more frequent in children than in adults (p < 0.05). Overall clinical outcome was good in 48.07% of the patients and poor in 51.92%. Patients with Type TS recurrent tumors had significantly worse functional outcomes and hypothalamic function than patients with the Type I recurrent tumors but better pituitary function especially in children.

CONCLUSIONS

The origin of recurrent craniopharyngiomas significantly affected the symptoms, signs, functional outcomes, and hypothalamic-pituitary functions of patients undergoing repeated surgery. Differences in tumor growth patterns and site of origin should be considered when one is comparing outcomes and survival across treatment paradigms in patients with recurrent craniopharyngiomas.

Growth patterns of craniopharyngiomas: clinical analysis of 226 patients

OBJECT Craniopharyngiomas (CPs) are rare epithelial tumors that are often associated with an enigmatic and unpredictable growth pattern. Understanding the growth patterns of these tumors has a direct impact on surgical planning and may enhance the safety of radical tumor removal. The aim of this study was to analyze the growth patterns and surgical treatment of CPs with a focus on the involvement of the hypothalamopituitary axis and the relationship of the tumor to the arachnoid membrane and surrounding structures. METHODS Clinical data from 226 consecutive patients with primary CP were retrospectively reviewed. Tumor location and the relationship of the tumor to the third ventricle floor and the pituitary stalk were evaluated using preoperative MRI and intraoperative findings. A topographic classification scheme was proposed based on the site of tumor origin and tumor development. The clinical relevance of this classification on patient presentation and outcomes was also analyzed. RESULTS The growth of CPs can be broadly divided into 3 groups based on the site of tumor origin and on tumor-meningeal relationships: Group I, infrasellar/infradiaphragmatic CPs (Id-CPs), which mainly occurred in children; Group II, suprasellar subarachnoid extraventricular CPs (Sa-CPs), which were mainly observed in adults and rarely occurred in children; and Group III, suprasellar subpial ventricular CPs (Sp-CPs), which commonly occurred in both adults and children. Tumors in each group may develop complex growth patterns during vertical expansion along the pituitary stalk. Tumor growth patterns were closely related to both clinical presentation and outcomes. Patients with Sp-CPs had more prevalent weight gain than patients with Id-CPs or Sa-CPs; the rates of significant weight gain were 41.7% for children and 16.7% for adults with Sp-CPs, 2.2% and 7.1% for those with Id-CPs, and 12.5% and 2.6% for those with Sa-CPs (p < 0.001). Moreover, patients with Sp-CPs had increased hypothalamic dysfunction after radical removal; 39% of patients with Sp-CPs, 14.5% with Id-CPs, and 17.4% with Sa-CPs had high-grade hypothalamic dysfunction in the first 2 postoperative years (p < 0.001). CONCLUSIONS The classification of CPs based on growth pattern may elucidate the best course of treatment for this formidable tumor. More tailored, individualized surgical strategies based on tumor growth patterns are mandatory to provide long-term tumor control and to minimize damage to hypothalamic structures. Differences in the distribution of growth patterns between children and adults imply that hierarchical comparison is necessary when investigating outcomes and survival across treatment paradigms in patients with CP.

Sir Victor Horsley: pioneer craniopharyngioma surgeon

Sir Victor Horsley (1857–1916) is considered to be the pioneer of pituitary surgery. He is known to have performed the first surgical operation on the pituitary gland in 1889, and in 1906 he stated that he had operated on 10 patients with pituitary tumors. He did not publish the details of these procedures nor did he provide evidence of the pathology of the pituitary lesions operated on. Four of the patients underwent surgery at the National Hospital for Neurology and Neurosurgery (Queen Square, London), and the records of those cases were recently retrieved and analyzed by members of the hospital staff. The remaining cases corresponded to private operations whose records were presumably kept in Horsley's personal notebooks, most of which have been lost.

In this paper, the authors have investigated the only scientific monograph providing a complete account of the pituitary surgeries that Horsley performed in his private practice, La Patologia Chirurgica dell'Ipofisi (Surgical Pathology of the Hypophysis), written in 1911 by Giovanni Verga, Italian assistant professor of anatomy at the University of Pavia. They have traced the life and work of this little-known physician who contributed to the preservation of Horsley's legacy in pituitary surgery. Within Verga's pituitary treatise, a full transcription of Horsley's notes is provided for 10 pituitary cases, including the patients' clinical symptoms, surgical techniques employed, intraoperative findings, and the outcome of surgery. The descriptions of the topographical and macroscopic features of two of the lesions correspond unmistakably to the features of craniopharyngiomas, one of the squamous-papillary type and one of the adamantinomatous type. The former lesion was found on necropsy after the patient's sudden death following a temporal osteoplastic craniectomy. Surgical removal of the lesion in the latter case, with the assumed nature of an adamantinomatous craniopharyngioma, was successful. According to the evidence provided in Giovanni Verga's monograph, it can be claimed that Sir Victor Horsley was not only the pioneer of pituitary gland surgery but also the pioneer of craniopharyngioma surgery.

A membranous structure separating the adenohypophysis and neurohypophysis: an anatomical study and its clinical application for craniopharyngioma

OBJECT This study aimed to identify the membranous septation between the adeno- and neurohypophysis. The clinical impact of this septation in the surgical removal of infradiaphragmatic craniopharyngioma (Id-CP) is also clarified. METHODS The sellar regions from 8 fetal and 6 adult cadavers were dissected. After staining first with H & E and then with picro-Sirius red, the membranous structures were observed and measured under normal light and polarization microscopy. The pre- and postsurgical images and intraoperative procedures in 28 cases of childhood Id-CP were reviewed and analyzed. RESULTS There is a significant membranous septation (termed the adenoneurohypophysis septation [ANHS]) lying behind the intermediate lobe to separate the adeno- and neurohypophysis. The average thicknesses are 21.9 ± 16.9 μm and 79.1 ± 43.2 μm in fetal and adult heads, respectively. The median segment of the septation is significantly thicker than the upper and lower segments. The ANHS extends from the suprasellar pars tuberalis to the sellar floor, where it is fused with the pituitary capsule. During Id-CP surgery performed via a transcranial approach, the ANHS can be identified to reserve the neurohypophysis. Moreover, by understanding the anatomy of this membrane, the pituitary stalk was preserved in 3 patients (10.7%). CONCLUSIONS There is a significant membrane separating the anterior and posterior lobes of the pituitary gland, which lies behind the intermediate lobe. Understanding the anatomy of this septation is important for identifying and preserving the neurohypophysis and pituitary stalk during Id-CP surgery.

Indication and limitations of endoscopic extended transsphenoidal surgery for craniopharyngioma

The transsphenoidal approach has been utilized in intrasellar craniopharyngioma surgeries. However, the advent of endoscopic extended transsphenoidal approach (EETSA) has expanded its indication to suprasellar craniopharyngiomas. We compared the indication and limitations of EETSA to those of uni-lateral basal interhemispheric approach (UBIHA), which presents similar indications for surgery. We analyzed 30 patients with tumors located below the foramen of Monro and the lateral boundary extending slightly beyond the internal carotid artery (UBIHA: N = 18; EETSA: N = 12). Postoperative magnetic resonance imaging (MRI) revealed gross total resection in 10 patients in the EETSA group (83.3%) and 12 in the UBIHA group (66.7%). Postoperative MRI in the EETSA group revealed residual tumor at the cavernous sinus in one patient, at the prepontine in one; in the UBIHA group, residual tumors were located in the retrochiasmatic area in two patients, infundibulum-hypothalamus in one, on the stalk in one, and in the intrasellar region in two. No intergroup differences were observed in the preservation of pituitary function and postoperative improvement of visual function. The extent of resection was better with EETSA than with UBIHA. EETSA is considered the first-line therapy because the distance between the optic chiasm and the superior border of the pituitary is large; the lateral extension does not go beyond the internal carotid artery; and the tumor does not extend inferiorly beyond the posterior clinoid process. However, in patients showing poorly developed sphenoid sinuses or pituitary stalks anterior to the tumor, surgery is difficult regardless of the selection criteria.

Extended endoscopic transsphenoidal approach infrachiasmatic corridor

An extended endoscopic transsphenoidal approach is required for skull base lesions extending to the suprasellar area. Inferior approach using the infrachiasmatic corridor allows access to the lesions through the tumor growth that is favorable for the extended transsphenoidal approaches. Infrachiasmatic corridor is a safer route for the inferior approaches that is made up by basal arachnoid membrane and Liliequist's membrane with its leaves (diencephalic and mesencephalic leaf). This area extends from the optic canal and tuberculum sella to the corpus mamillare. We performed extended endoscopic approach using the infrachiasmatic corridor in 52 cases, including tuberculum sella meningiomas (n:23), craniopharyngiomas (n:16), suprasellar Rathke's cleft cyst (n:6), pituitary adenoma (n:2), fibrous dysplasia (n:1), infundibular granulosa cell tumor (n:2), and epidermoid tumor (n:2). Total resection was achieved in 17 of 23 (74%) with tuberculum sellae meningioma using infrachiasmatic approach. Twenty patients presented with visual disorders and 14 of them improved. There were two postoperative cerebrospinal fluid (CSF) leakages and one transient diabetes insipidus and one permanent diabetes insipidus. Sixteen patients were operated on by the infrachiasmatic approach for craniopharyngiomas. Improvement was reached in seven of eight patients presented with visual disorders. Complete tumor resection was performed in 10 of 16 cases and cyst aspiration in 4 cases, and there were remnants in two cases. Postoperative CSF leakage was seen in two patients. Infrachiasmatic corridor provides an easier and safer inferior route for the removal of middle midline skull base lesions in selected cases.

Development of intracranial approaches for craniopharyngiomas: an analysis of the first 160 historical procedures

Object

The development of surgical procedures for the removal of craniopharyngiomas (CPs) was greatly influenced by the enormous topographical and morphological heterogeneity displayed by these lesions. In this study the authors reviewed the intracranial approaches designed to treat CPs during the early historical period (1891–1938) with the aim of finding the CP topographical and pathological features that influence patient outcomes.

Methods

The authors conducted a systematic retrospective review of well-described cases of surgically treated CPs in publications from the period 1891–1938. Valuable information regarding the diagnosis of the lesion, type of craniotomy performed, CP topography, and outcome was selected from 418 reports included in medical publications from this period. The type of surgical procedure used, degree of tumor removal, CP position and histological variety, and clinical evidence of postoperative hypothalamic injury were the variables analyzed with the aim of defining their influence on the final patient outcome.

Results

A collection of 160 cases was eligible for analysis. Craniopharyngioma topography was significantly related to the existence of postoperative hypothalamic damage and the degree of tumor removal achieved (p < 0.001). The infundibulo-tuberal, or not strictly intraventricular, topography was associated with the highest rate of hypothalamic injury (84%) and impossibility of tumor removal (51%). This topography also showed the worst prognosis (p = 0.001). Additional variables correlated with patient outcome were the presence of hypothalamic damage, type of surgical approach used, and degree of tumor removal. Patients having a poor outcome, suffering from permanent coma, or dying after surgery presented with symptoms of hypothalamic injury in 40% of cases (p < 0.001). The surgical approach associated with the best outcome was the transsphenoidal (58%), followed by the subfrontal (45%) and the transcallosal (45%). Subtotal resection of the lesion yielded the best postoperative results, with only 17% of patients dying or suffering from a poor outcome, in contrast to the 39% reported for gross-total removal of the lesion (p = 0.001).

Conclusions

Two major variables influenced the results of early surgical experience with CPs for the period from 1891 to 1938: 1) the inaccuracy in defining CP topography with the diagnostic methods available at that time; and 2) the ignorance about the risks associated with the dissection of lesions showing tenacious adherence to the hypothalamus. The degree of functional and morphological disturbance of the hypothalamus caused by a CP remains a fundamental variable helping the surgeon to predict the risks associated with the radical excision of the tumor and patient outcome.

Pituitary stalk management during the microsurgery of craniopharyngiomas

In the present study, 203 patients that had previously undergone microsurgery for craniopharyngiomas (CPs) between 1992 and 2012 were analyzed retrospectively on a long-term follow-up basis to investigate the differences in the recurrence rate and endocrine function between patients with preserved and resected pituitary stalks. To summarize the possible outcomes of microsurgery, the 203 patients were divided into 2 groups: Group A that had preserved pituitary stalks and Group B that had undergone resections of the pituitary stalk. Tumor origins and the involvement of the pituitary stalk during surgery were observed. From 2010 onwards, an ultra-electron microscope was used postoperatively to detect whether pituitary stalk specimens were infiltrated or invaded with tumor cells. Long-term follow-up observations of the patients included tumor recurrence, postoperative endocrine dysfunction and visual acuity and field. Among the 203 patients, 175 patients received gross-total resection (GTR) (175/203, 86.2%), 28 patients underwent subtotal resection (28/203, 13.8%) and 34 patients had surgery that preserved the pituitary stalk (34/203, 16.7%). There was no significant difference in the recurrence rate between Group A (4/34, 11.8%) and the patients in Group B (10/123, 8.1%) who underwent GTR and also received follow-ups. Of the 157 patients who were followed up, 91 individuals underwent endocrine evaluation and the outcome was divided into normal, satisfactory and poor grades. The results for Group A were 5, 18 and 0, respectively, while the results for Group B were 1, 60 and 7, respectively, which showed a statistically significant difference between the groups. Pituitary stalk specimens of 15 patients were studied postoperatively using an ultra-electron microscope and all samples showed tumor cells had invaded the pituitary stalk (15/15, 100%). Total resections of CPs with the pituitary stalk were recommended if the pituitary stalk was intraoperatively invaded. In cases where the pituitary stalk was not involved, microsurgical excisions preserving the pituitary stalk were preferred, as there was no significant increase in the recurrence rate and the patients experienced less endocrine dysfunction.

Growth and weight of children with craniopharyngiomas based on the tumour location and growth pattern

This study aimed to characterise the weight and growth of children with craniopharyngiomas and to analyse the role of the tumour location and growth pattern in the development of obesity and growth retardation in these children. We retrospectively analysed the records of 109 consecutive children with primary craniopharyngiomas. The patients were divided into two subgroups according to the location of the tumour: intrasellar (Group A); and the floor of the third ventricle (Group B). Height and body mass index were measured at standardised ages and at time points before, after, and at the time of diagnosis. Endocrinological and hypothalamic measurements before and after surgery were compared. Reduced growth rates occurred in early infancy and persisted until diagnosis in Group A, but were only present from age 5-6 in Group B. Therefore, reduced growth rates occur early in the history of intrasellar tumours, whereas rapid postoperative weight gain invariably occurs in patients with third ventricle tumours, which is a significant predictive factor for severe long term obesity in patients with childhood craniopharyngiomas.