Infundibulo-tuberal or not strictly intraventricular craniopharyngioma: evidence for a major topographical category

Papillary Craniopharyngioma: An Integrative and Comprehensive Review

Papillary craniopharyngioma (PCP) is a rare type of tumor, comprising ∼20% of all craniopharyngioma (CP) cases. It is now recognized as a separate pathological entity from the adamantinomatous type. PCPs are benign tumors, classified as World Health Organization grade 1, characterized by nonkeratinizing squamous epithelium. They typically grow as solid and round papillomatous masses or as unilocular cysts with a cauliflower-like excrescence. PCPs primarily occur in adults (95%), with increased frequency in males (60%), and predominantly affect the hypothalamus. Over 80% of these tumors are located in the third ventricle, expanding either above an anatomically intact infundibulum (strictly third ventricle tumors) or within the infundibulo-tuberal region of the third ventricle floor. Clinical manifestations commonly include visual deficits and a wide range of psychiatric disturbances (45% of patients), such as memory deficits and odd behavior. Magnetic resonance imaging can identify up to 50% of PCPs by the presence of a basal duct-like recess. Surgical management is challenging, requiring complex approaches to the third ventricle and posing significant risk of hypothalamic injury. The endoscopic endonasal approach allows radical tumor resection and yields more favorable patient outcomes. Of intriguing pathogenesis, over 90% of PCPs harbor the somatic BRAFV600E mutation, which activates the mitogen-activated protein kinase signaling pathway. A phase 2 clinical trial has demonstrated that PCPs respond well to proto-oncogene B-Raf/MAPK/ERK kinase inhibitors. This comprehensive review synthesizes information from a cohort of 560 well-described PCPs and 99 large CP series including PCP cases published from 1856 to 2023 and represents the most extensive collection of knowledge on PCPs to date.

BRAF and MEK inhibitor targeted therapy in papillary craniopharyngiomas: a cohort study

OBJECTIVE

Targeted therapy (TT) with BRAF/MEK inhibitors has emerged as a potential treatment in papillary craniopharyngiomas (PCPs). However, standardized data on large cohorts are lacking. Our study aimed to assess real-life efficacy and safety of BRAF/MEK inhibition in patients with PCPs.

DESIGN

Retrospective French multicenter study involving BRAF V600E-mutated PCP patients, treated with BRAF/MEK inhibitor combination dabrafenib and trametinib, from April 2019 to July 2023.

METHODS

Objective response and clinical and safety outcomes were assessed after 3 months and at the last available follow-up during TT.

RESULTS

Sixteen patients (8 females, mean age 50.5 ± 15.75 years), receiving either neoadjuvant therapy (NEO) for non-resectable tumors (n = 6), post-surgical adjuvant therapy (ADJ; n = 8), or palliative therapy (PAL) following failure of multimodal treatment (n = 2), were included.At the last follow-up (mean 7.6 ± 5.3 months), 12 patients showed subtotal response, 3 exhibited partial response, and 1 maintained stable disease. Mean volume reduction was 88.9 ± 4.4%, 73.3 ± 23.4%, and 91.8 ± 4.3% in the NEO, ADJ, and PAL groups, respectively.Targeted therapy resolved headaches in 5/5 patients and visual impairment in 6/9; 2/3 patients had improved neurological symptoms, 1/4 presented weight loss, and 2/14 recovered endocrine function.Targeted therapy was well-tolerated in 62.5% of cases; adverse events led to treatment discontinuation in 5 patients and definitive discontinuation in 3 cases.

CONCLUSIONS

In this study, 94% of patients showed partial response or better to TT. Adverse events were acceptable. Further research is needed to establish standardized protocols; however, these results advocate for a NEO approach in invasive PCPs.

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.

Prognostic Impact of Hypothalamic Perforation in Adult Patients With Craniopharyngioma: A Cohort Study

CONTEXT

Outcome of craniopharyngioma is related to its locoregional extension, which impacts resectability and the risk of surgical complications. To maximize resection and minimize complications, optic tract localization, temporal lobe extension, and hypothalamic involvement are essential factors for surgical management.

OBJECTIVE

To assess the outcome of craniopharyngiomas depending on their relation to the hypothalamus location.

METHODS

We conducted a retrospective analysis of 79 patients with a craniopharyngioma who underwent surgery from 2007 to 2022. Craniopharyngiomas were classified in 3 groups, depending on the type of hypothalamus involvement assessed by preoperative magnetic resonance imaging: infra-hypothalamic (type A, n = 33); perforating the hypothalamus (type B, n = 40); and supra-hypothalamic (type C, n = 6). Surgical strategy was guided by the type of hypothalamic involvement, favoring endonasal approaches for type A and type B, and transcranial approaches for type C.

RESULTS

Long-term disease control was achieved in 33/33 (100%), 37/40 (92%), and 5/6 (83%) patients in type A, B, and C, respectively. In type B, vision was improved in 32/36 (89%) patients, while hypothalamic function was improved, stable, or worsened in 6/40 (15%), 32/40 (80%), and 2/40 (5%) patients, respectively. Papillary craniopharyngiomas were found in 5/33 (15%), 9/40 (22%), and 3/6 (50%) patients in types A, B, and C, respectively. In 4 patients, BRAF/MEK inhibitors were used, with significant tumor shrinkage in all cases.

CONCLUSION

Craniopharyngiomas located below the hypothalamus or perforating it can be safely treated by transsphenoidal surgery. For supra-hypothalamic craniopharyngiomas, postoperative results are less favorable, and documenting a BRAF mutation may improve outcome, if targeted therapy was efficient enough to replace surgical debulking.

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.

Current Advances in Papillary Craniopharyngioma: State-Of-The-Art Therapies and Overview of the Literature

Craniopharyngiomas are commonly classified as low-grade tumors, although they may harbor a malignant behavior due to their high rate of recurrence and long-term morbidity. Craniopharyngiomas are classically distinguished into two histological types (adamantinomatous and papillary), which have been recently considered by the WHO classification of CNS tumors as two independent entities, due to different epidemiological, radiological, histopathological, and genetic patterns. With regard to papillary craniopharyngioma, a BRAF V600 mutation is detected in 95% of cases. This genetic feature is opening new frontiers in the treatment of these tumors using an adjuvant or, in selected cases, a neo-adjuvant approach. In this article, we present an overview of the more recent literature, focusing on the specificities and the role of oncological treatment in the management of papillary craniopharyngiomas. Based on our research and experience, we strongly suggest a multimodal approach combining clinical, endocrinological, radiological, histological, and oncological findings in both preoperative workup and postoperative follow up to define a roadmap integrating every aspect of this challenging condition.

Endoscopic endonasal treatment of craniopharyngiomas: current management strategies and future perspectives

INTRODUCTION

Craniopharyngiomas are locally aggressive disembryogenetic tumors presenting mostly in childhood and late adulthood. They are often burdened by an unfavorable clinical course due to close relationships with nearby critical neurovascular structures and high risk of recurrences. The aim of our paper is to provide a systematic review of the literature regarding current strategies and future perspectives for the treatment of craniopharyngiomas, focusing on the role of endoscopic endonasal surgery.

EVIDENCE ACQUISITION

A comprehensive literature search of three databases (PubMed, Ovid Medline, and Ovid Embase) has been conducted to identify papers addressing the management strategies in adult and pediatric craniopharyngioma patients.

EVIDENCE SYNTHESIS

Twenty-two articles have been included, providing data for 560 adult and 215 pediatric patients. Mean follow-up was 40.29 months for the adult and 58.05 months for pediatric population. GTR rate was 60.97% and 82.52% in adult and pediatric patients, respectively. Adjuvant radiotherapy was delivered in 20.99% of adult and 8.25% of pediatric cases; 89% of adult patients and 94.11% of pediatric patients receiving radiotherapy had previously undergone NTR, STR or partial resection. The recurrence rate was 19.32% and 18.61% for adult and pediatric population, respectively. Recurrences occurred mostly in patients receiving incomplete resection without adjuvant radiotherapy (72.87% in adults and 51.28% in children); 86.69% and 87.12% of adult and pediatric patients reported improvement of their previous ophthalmologic deficit; 40% of the adult population and 41.86%% of pediatric patients worsened or developed endocrinological disturbances. CSF leak rate was 16.4% in adults and 13.95%% in children.

CONCLUSIONS

Modern policy of craniopharyngioma management is represented by the combination of a "maximum safe" allowed surgical removal plus radiotherapy. In this scenario, the endoscopic endonasal technique proved to be a valid approach for removing these lesions, providing satisfactory outcomes with lower morbidity.

Duct-like diverticulum at the base of third ventricle tumors: a morphological signature diagnostic of papillary craniopharyngioma

This study describes and characterizes a narrow, hollow tubular structure, termed as duct-like diverticulum (DV), found specifically at the basal midline of papillary craniopharyngiomas (PCPs) located within the third ventricle (3V). The presence of this structure was systematically investigated on autopsy studies and magnetic resonance imaging (MRI) scans of 3536 craniopharyngioma (CP) cases published in the medical literature from 1911 to 2021, as well as in other twelve 3V tumor categories (n = 1470 cases). A basal DV was observed in a total of 50 PCPs, including two of our own cases. This DV corresponds to a tubular-shaped recess invaginated at the midline bottom of the tumor, following the same angled trajectory as the pituitary stalk. It can be easily seen as a hypointense linear structure on T1- and T2-weighted MRI scans, with two main length types: long DVs (74%), which reach the tumor center, and short DVs (26%), which penetrate the tumor only a few millimeters. The DV sign identifies the papillary CP type with a specificity of 100% and a sensitivity of 33% in the overall CP population. This finding also serves to establish the strictly intra-3V location of the lesion with a 95% specificity and 42% sensitivity among papillary CPs. No similar basal DV was found in adamantinomatous CPs nor among other categories of strictly 3V tumors. Consequently, the presence of a diverticulum in a 3V tumor represents a morphological signature pathognomonic of the papillary type and a valuable sign to reliably define the strictly 3V topography.

Basal Recess in Third Ventricle Tumors: A Pathological Feature Defining a Clinical-Topographical Subpopulation of Papillary Craniopharyngiomas

This study investigates the presence of a hollow recess at the midline undersurface of tumors primarily localized within the third ventricle (3V). This structure was originally identified by magnetic resonance imaging (MRI) of 6 3V craniopharyngiomas (CPs) from our series and was then methodically scrutinized in autopsy studies (n = 1091) and MRI scans (n = 5558) of CPs and in 1251 3V tumors reported in the medical literature from 1839 to 2021. A recess at the tumor base was identified in 110 CPs, 95 with a verified papillary histology (papillary craniopharyngioma [PCP]) and 15 with typical gross appearance of PCP. Topographically, 90 tumors were strictly within the 3V (82%); 20 developed at the infundibulo-tuberal region of the 3V floor (18%). Morphologically, 2 main types of recess were identified: (i) a long, narrow recess with either a duct-like or a tubular shape that reached the central region of the CP (n = 47, 42.5%); and (ii) a short recess extending only a few millimeters into the lesion, either with a duct-like or a shallow cleft-like morphology (n = 63, 57.5%). Thus, the presence of a basal recess represents a pathological hallmark of a subpopulation of 3V PCPs. The presumed nature and diagnostic significance of this novel finding is comprehensively addressed.

Papillary Craniopharyngioma: A Type of Tumor Primarily Impairing the Hypothalamus - A Comprehensive Anatomo-Clinical Characterization of 350 Well-Described Cases

OBJECTIVE

Papillary craniopharyngiomas (PCPs) represent a rare histological type of craniopharyngiomas (CPs) usually involving the hypothalamus. This study systematically analyzes the clinical-anatomical correlation between tumor topography and symptoms related to hypothalamic dysfunction in the largest series of PCPs ever gathered.

METHODS

From 5,346 CP reports published from 1856 to 2021, we selected 350 well-described cases of the squamous-papillary type. Clinical presentation, tumor topography, severity of hypothalamic adhesion, patient outcome, and tumor recurrence were thoroughly analyzed.

RESULTS

PCPs predominantly occur in adult (96.3%), male (61.7%) patients presenting with headache (63.4%), visual alterations (56.2%), and psychiatric disturbances (50.4%). Most PCPs are solid (50%), round (72%) lesions that occupy the third ventricle (3V, 94.8%) and show low-risk severity adhesions to the hypothalamus (66.8%). Two major topographical categories can be found: strictly 3V (57.5%), growing above an intact 3V floor, and not-strictly or infundibulo-tuberal (32.9%), expanding at the infundibulum and/or tuber cinereum. The hypothalamic syndrome predominated among strictly 3V PCPs (p < 0.001). Psychiatric symptoms (p < 0.001) and high-risk hypothalamic attachments (p = 0.031) related to unfavorable postoperative outcomes among patients treated from 2006 onwards. The not-strictly 3V topography was identified as the major predictor of high-risk hypothalamic attachments (71.2% correctly predicted), which, along with incomplete tumor removal (p = 0.018), underlies the higher tumor recurrence of this topography (p = 0.001).

CONCLUSIONS

This systematic review evidences that PCP topography is a major determinant of hypothalamic-related symptoms, type of hypothalamic attachments, and tumor recurrence rate. Accurate preoperative definition of PCP-hypothalamus relationships is essential for the judicious, safe management of these complex lesions.

Neoadjuvant B-RAF and MEK Inhibitor Targeted Therapy for Adult Papillary Craniopharyngiomas: A New Treatment Paradigm

BACKGROUND

Surgical and clinical management of craniopharyngiomas is associated with high long-term morbidity especially in the case of hypothalamic involvement. Improvements in knowledge of craniopharyngioma molecular biology may offer the possibility of safe and effective medical neoadjuvant treatments in a subset of patients harboring papillary subtype tumors with a BRAFV600E mutation.

METHOD

We report herein two cases of tubero-infundibular and ventricular Papillary Craniopharyngiomas in which BRAF/MEK inhibitor combined therapy was used as adjuvant (Case 1) or neoadjuvant (Case 2) treatment, with a 90% reduction in tumor volume observed after only 5 months. In Case 2 the only surgical procedure used was a minimal invasive biopsy by the trans-ventricular neuroendoscopic approach. As a consequence, targeted therapy was administered in purely neoadjuvant fashion. After shrinkage of the tumor, both patients underwent fractionated radiotherapy on the small tumor remnant to achieve long-term tumor control. A review of a previously reported case has also been performed.

RESULT

This approach led to tumor control with minimal long-term morbidity in both cases. No side effects or complications were reported after medical treatment and adjuvant radiotherapy.

CONCLUSION

Our experience and a review of the literature argue for a change in the current treatment paradigm for Craniopharyngiomas (CPs). In giant and invasive tumors, confirmation of BRAFV600E mutated PCPs by biopsy and BRAF/MEK inhibitor therapy before proposing other treatments may be useful to improve long term outcomes for patients.

Relationship between postoperative hypothalamic injury and water and sodium disturbance in patients with craniopharyngioma: A retrospective study of 178 cases

OBJECTIVE

To investigate the relationship between postoperative hypothalamo-hypophyseal injury (HHI) and postoperative water and sodium disturbances in patients with craniopharyngioma.

METHODS

The medical records, radiological data, and laboratory results of 178 patients (44 children and 134 adults) who underwent microsurgery for craniopharyngioma in a single center were reviewed. Postoperative HHI was assessed using magnetic resonance imaging. Structural defects of the hypothalamo-hypophyseal system (pituitary, pituitary stalk, floor and lateral wall of the third ventricle) were assessed in four standard T1-weighted images. The defect of each structure was assigned 1 score (0.5 for the unilateral injury of the third ventricle wall), and a HHI score was calculated.

RESULTS

The number of patients with HHI scores of 0-1, 2, 2.5-3, and >3 was 35, 49, 61, and 33, respectively. Diabetes insipidus (DI) worsened in 56 (31.5%) patients with preoperative DI, while 119 (66.9%) patients were diagnosed with new-onset DI. Hypernatremia and hyponatremia developed in 127 (71.3%) and 128 (71.9%) patients after surgery, respectively. Syndrome of inappropriate antidiuresis occurred in 97(54.5%) patients. During hospitalization, hypernatremia recurred in 33 (18.5%) patients and in 54 (35.7%) during follow-up, of which 18 (11.9%) were severe. DI persisted in 140 (78.7%) patients before discharge. No relationship was found between the HHI score and incidence of early DI, hyponatremia, syndrome of inappropriate diuretic hormone, or prolonged DI. Compared with patients with a score of 0-1, those with scores =2.5-3 (OR = 5.289, 95% CI:1.098-25.477, P = 0.038) and >3 (OR = 10.815, 95% CI:2.148-54.457, P = 0.004) had higher risk of developing recurrent hypernatremia. Patients with a score >3 had higher risk of developing severe hypernatremia during hospitalization (OR = 15.487, 95% CI:1.852-129.539, P = 0.011) and at follow-up (OR = 28.637, 95% CI:3.060-267.981, P = 0.003).

CONCLUSIONS

The neuroimaging scoring scale is a simple tool to semi-quantify HHI after surgery. Recurrent and severe hypernatremia should be considered in patients with a high HHI score (>2.5). An HHI score >3 is a potential predictor of adipsic DI development. Preventive efforts should be implemented in the perioperative period to reduce the incidence of potentially catastrophic complications.

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.

Intraventricular Craniopharyngiomas-Overcoming Their Relative Inaccessibility: Institutional Experience With a Review of Literature

Introduction: Craniopharyngiomas constitute 2-4% of intracranial neoplasms. Intraventricular craniopharyngiomas (IVCrs) are the rarely encountered varieties of these lesions. Objective: The objective of the study was to study the special features in clinical presentation, imaging, management, and surgical outcome of IVCrs. Materials and Methods: This retrospective analysis included the combined experience from two tertiary care institutions. Medical records of histopathologically proven cases of IVCrs from January 1994 to June 2021 were assessed, and images were analyzed based on the criteria by Migliore et al. for inclusion of solely intraventricular lesion with the third ventricular ependyma demarcating it from the suprasellar cistern. Results: Among the 25 patients included (mean age: 35.4 years), the most common presentation included headache (n = 21, 84%), vomiting and other features of raised ICP (n = 18, 72%), visual complaints (n = 12, 48%), and endocrinopathies (n = 11, 44%). Fifteen had predominantly cystic tumors, two were purely solid, and eight were of mixed consistency. Primary open microsurgical procedures were performed in 18 (72%) patients, of which four (16%) were endoscope-assisted. Seven (28%) underwent a purely endoscopic procedure. One underwent a staged surgery with endoscopic cyst fenestration and intracystic interferon (IFN)-alpha therapy, followed by microsurgical excision. Complete excision was achieved in 10 patients, near-total in nine, and partial excision in six. Four patients underwent a ventriculoperitoneal shunt (one before the definitive procedure). At a median follow-up of 36 months (range:11-147 months), five patients developed a recurrence, and one had a stable small residue. This patient and two others with small cystic recurrences were observed. One patient was managed with radiotherapy alone. Another underwent re-surgery after a trial of radiotherapy, and the last patient developed a local recurrence, which was managed with radiotherapy; he then later developed an intraparenchymal recurrence, which was operated. Conclusion: Purely IVCrs present with raised intracranial pressure, and visual disturbances are less common. Their deep-seated location and limited surgical field-of-view makes minimally invasive endoscopic-assisted surgery most suitable for their excision. The thin-walled cystic lesions may be occasionally adherent to the ependymal wall in close vicinity to the thalamus-hypothalamus complex, making complete excision difficult. Their responsiveness to radiotherapy, often leads to a gratifying long-term outcome.

Strictly third ventricle craniopharyngiomas: pathological verification, anatomo-clinical characterization and surgical results from a comprehensive overview of 245 cases

The strictly third ventricle craniopharyngioma topography (strictly 3V CP) defines the subgroup of lesions developed above an anatomically intact third ventricle floor (3VF). The true existence of this exceedingly rare topographical category is highly controversial owing to the presumed embryological CP origin from Rathke's pouch, a structure developmentally situated outside the neural tube. This study thoroughly analyzes the largest series of strictly 3V CPs ever collected. From 5346 CP reports published between 1887 and 2021, we selected 245 cases with reliable pathological, surgical, and/or neuroradiological verification of an intact 3VF beneath the tumor. This specific topography occurs predominantly in adult (92.6%), male (64.4%) patients presenting with headache (69.2%), and psychiatric disturbances (59.2%). Neuroradiological features defining strictly 3V CPs are a tumor-free chiasmatic cistern (95.9%), an entirely visible pituitary stalk (86.4%), and the hypothalamus positioned around the tumor's lower pole (92.6%). Most are squamous papillary (82%), showing low-risk severity adhesions to the hypothalamus (74.2%). The adamantinomatous variant, however, associates a higher risk of severe hypothalamic adhesion (p < .001). High-risk attachments are also associated with psychiatric symptoms (p = .013), which represented the major predictor for unfavorable prognoses (83.3% correctly predicted) among cases operated from 2006 onwards. CP recurrence is associated with infundibulo-tuberal symptoms (p = .036) and incomplete surgical removal (p = .02). The exclusive demographic, clinico-pathological and neuroradiological characteristics of strictly 3V CPs make them a separate, unique topographical category. Accurately distinguishing strictly 3V CPs preoperatively from those tumors replacing the infundibulum and/or tuber cinereum (infundibulo-tuberal or not strictly 3V CPs) is critical for proper, judicious surgical planning.

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.

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.

Beyond the bipolar disorder diagnosis: Hypothalamus and its network damage in determining neuropsychiatric and Korsakoff-like memory disorders

Craniopharyngiomas (CP's) are hypothalamic tumors often associated with psychological disorders. Nevertheless, its diagnosis is still challenging when psychiatric disorders are not associated with any other neurological symptoms. This single-case study describes a patient with a history of bipolar disorder before a diagnosis of a large CP arising the sellar and suprasellar region was posed. At the time of the present study the patient showed emotional/behavioral disorders and Korsakoff-like amnesia, that completely recovered after surgical resection of the tumor. This is one of those few cases described in literature, who presented cognitive/behavioral disorders because the compression of the diencephalic structures due to CP mass effect. This case offers further evidence on the functional neuroanatomy of the hypothalamus and its pathways.

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.

Percival S. Bailey: eminent scholar of neurosciences who revealed the workings of the hypothalamus through clinicopathological research on craniopharyngiomas

Percival S. Bailey (1892-1973) was a scholar, neuroscientist, neuropathologist, and neurosurgeon who made decisive contributions in the field of neuro-oncology. Far less known are his groundbreaking insights into understanding hypothalamic physiology through the study of craniopharyngiomas. As one of Harvey W. Cushing's most talented trainees, Bailey was instrumental in developing Cushing's project of a histologically based prognostic classification of brain tumors. He worked at Peter Bent Brigham Hospital on and off between 1919 and 1928, owing to frequent clashes with his mentor. A major cause of this long-term conflict was Bailey's 1921 experimental demonstration of the hypothalamic origin of diabetes insipidus and Fröhlich's syndrome. This finding challenged Cushing's view that both alterations were due to pituitary gland insufficiency. In a seminal monograph written with John F. Fulton in 1929, both authors provided the first comprehensive account of the specific hypothalamic disturbances caused by tumors that originated within the infundibulum and third ventricle. The methodical study of Cushing's craniopharyngioma specimens allowed Bailey to recognize the close contact between these lesions and hypothalamic nuclei, a key concept that Bailey originally advanced for proper surgical planning. This article aims to credit Bailey for his pioneering definition of craniopharyngiomas as tumors with a true intrahypothalamic position.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

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.

Chemical meningitis in children as a risk factor following craniopharyngioma resection - a case report

BACKGROUND

Craniopharyngiomas are defined by the WHO as "benign" tumours, but their location and surgical treatment may be associated with major complications, one being chemical meningitis. Although rare, especially in children, it should be taken into account when worrying symptoms appear after surgery.

CASE PRESENTATION

The aim of this study is to present the case of chemical meningitis in a 7-year-old girl. She was admitted to the Department of Neurology with the following symptoms: headache, vomiting and balance disorders. Brain magnetic resonance imaging showed a tumour in the sellar and suprasellar region, which was diagnosed as a craniopharyngioma. Due to acute hydrocephalus the patient underwent emergency surgery. Conventional surgery was preceded by an endocrinological consultation to determine pituitary hormone levels. The first 6 days post-surgery, during which the patient started substitution therapy for pituitary insufficiency, were uneventful but on the seventh day she presented with seizures, fever, severe headache, weakness, irritability, stiffening of the neck and a gradual degradation of consciousness. This clinical presentation suggested meningitis, which was confirmed by examination of cerebrospinal fluid.

CONCLUSIONS

The conventional and/or endoscopic resection of a craniopharyngioma poses a risk of postoperative complications in the form of chemical meningitis. Although this is a rare occurrence in children with craniopharyngioma, physicians should be aware of this complication and its clinical presentation as it may facilitate earlier diagnosis, appropriate treatment and a faster recovery of their patients.

Interrater reliability of a method to assess hypothalamic involvement in pediatric adamantinomatous craniopharyngioma

OBJECTIVE

Pediatric adamantinomatous craniopharyngiomas (ACPs) are histologically benign brain tumors that confer significant neuroendocrine morbidity. Previous studies have demonstrated that injury to the hypothalamus is associated with worsened quality of life and a shorter lifespan. This insight helps many surgeons define the goals of surgery for patients with ACP. Puget and colleagues proposed a 3-tiered preoperative and postoperative grading system based on the degree of hypothalamic involvement identified on MRI. In a prospective cohort from their institution, the authors found that use of the system to guide operative goals was associated with decreased morbidity. To date, however, the Puget system has not been externally validated. Here, the authors present an interrater reliability study that assesses the generalizability of this system for surgeons planning initial operative intervention for children with craniopharyngiomas.

METHODS

A panel of 6 experts, consisting of pediatric neurosurgeons and pediatric neuroradiologists, graded 30 preoperative and postoperative MRI scans according to the Puget system. Interrater reliability was calculated using Fleiss' κ and Krippendorff's α statistics.

RESULTS

Interrater reliability in the preoperative context demonstrated moderate agreement (κ = 0.50, α = 0.51). Interrater reliability in the postoperative context was 0.27 for both methods of statistical evaluation.

CONCLUSIONS

Interrater reliability for the system as defined is moderate. Slight refinements of the Puget MRI grading system, such as collapsing the 3 grades into 2, may improve its reliability, making the system more generalizable.

Craniopharyngioma

Craniopharyngiomas are rare malformational tumours of low histological malignancy arising along the craniopharyngeal duct. The two histological subtypes, adamantinomatous craniopharyngioma (ACP) and papillary craniopharyngioma (PCP), differ in genesis and age distribution. ACPs are diagnosed with a bimodal peak of incidence (5-15 years and 45-60 years), whereas PCPs are restricted to adults mainly in the fifth and sixth decades of life. ACPs are driven by somatic mutations in CTNNB1 (encoding β-catenin) that affect β-catenin stability and are predominantly cystic in appearance. PCPs frequently harbour somatic BRAFV600E mutations and are typically solid tumours. Clinical manifestations due to increased intracranial pressure, visual impairment and endocrine deficiencies should prompt imaging investigations, preferentially MRI. Treatment comprises neurosurgery and radiotherapy; intracystic chemotherapy is used in monocystic ACP. Although long-term survival is high, quality of life and neuropsychological function are frequently impaired due to the close anatomical proximity to the optic chiasm, hypothalamus and pituitary gland. Indeed, hypothalamic involvement and treatment-related hypothalamic lesions frequently result in hypothalamic obesity, physical fatigue and psychosocial deficits. Given the rarity of these tumours, efforts to optimize infrastructure and international collaboration should be research priorities.

Harvey Cushing's craniopharyngioma treatment: Part 2. Surgical strategies and results of his pioneering series

OBJECTIVE

Harvey Cushing (1869-1939) developed pioneering surgical techniques for craniopharyngioma (CP) removal. This study exhaustively analyzes the pathological variables and surgical strategies that influenced Cushing's results in his entire series of CP patients.

METHODS

The CP records from Cushing's Brain Tumor Registry were carefully reviewed, as were his CP cases published in medical monographs and scientific reports.

RESULTS

One hundred twenty-four tumors with characteristics typical of CP comprise Cushing's entire series (CP124). Cushing performed 198 surgical procedures in the patients in whom these tumors were treated, with a 23% mortality rate within the first 2 months after surgery. Three periods in Cushing's CP surgical career can be differentiated: an early period (1901-1917, 39 patients) characterized by his use of the transsphenoidal approach and limited cyst drainage procedures, an intermediate period (1919-1925, 42 patients) in which the subfrontal approach was the standard procedure and maximal removal was attempted, and a late period (1926-1932, 43 patients) characterized by the use of air ventriculography for topographical diagnosis and limited resections via a transventricular approach. Among Cushing's CP series were 92 cases that were pathologically verified (CP92). In this subcohort, the unilateral subfrontal approach was predominantly used (72% of cases), followed by the transsphenoidal (15%) and frontal transcortical-transventricular (8%) approaches. Drainage of the CP cystic component or partial excision of the solid component was achieved in 61% of the cases, subtotal removal in 23%, and macroscopic total removal in 10%. Satisfactory outcomes were obtained in 55% of the patients in CP92, whereas poor outcomes and/or death related to hypothalamic injury was observed in 28%. Postoperative symptoms related to hypothalamic dysfunction occurred 53% of the time. The subfrontal approach yielded the highest rates of radical removal (p < 0.001) and good outcomes (p = 0.01). Partial removals were associated with the highest rates of poor outcomes, including death (p = 0.009). Cushing's removal of CPs with a primary infundibulo-tuberal topography or showing third ventricle invasion was associated with the highest rates of hypothalamic injury (p < 0.001) and the worst outcomes (p = 0.009).

CONCLUSIONS

Harvey Cushing's techniques and surgical philosophy varied substantially throughout his career. The experience he gained with this large CP series made him aware of the importance of limiting the extent of tumor removal and leaving untouched the tumor portion strongly adhered to the hypothalamus.

Harvey Cushing's craniopharyngioma treatment: Part 1. Identification and clinicopathological characterization of this challenging pituitary tumor

OBJECTIVE

Harvey Cushing (1869-1939) coined the term "craniopharyngioma" (CP) in 1929 to describe a kaleidoscopic group of epithelial tumors involving the hypothalamic-pituitary axis. Throughout his career, he endured a long struggle to accurately diagnose and safely remove these complex lesions, and his resulting surgical series has never before been analyzed in depth. The authors here conduct such an analysis.

METHODS

In this study, the authors retrospectively examined the CP patient records available in the Cushing Brain Tumor Registry, as well as those CP cases reported by Cushing in medical monographs and scientific reports.

RESULTS

Cushing's CP series comprises a total of 124 tumors (CP124) compatible with a CP diagnosis. Among this series are 92 cases that could be pathologically verified (CP92). This subcohort showed a bimodal age distribution (41% aged ≤ 19 years old) and a balanced sex distribution. Clinical evolution up to diagnosis was longer than 3 years in half of the patients. Typical symptoms found at diagnosis were severe headache (94%), visual deficits (97%), panhypopituitarism (76%), psychiatric disturbances (47%), and abnormal somnolence (47%). The highest rate of endocrine deficits occurred in patients younger than 19 years of age (p < 0.001), whereas hypothalamic disturbances were observed mainly in adults between 30 and 49 years (p = 0.02). Hydrocephalus was present in 63% of the patients, predominantly involving the younger subgroup (p < 0.001). Preoperative diagnosis was based on clinical signs, funduscopic exams, and skull radiographs, the latter study showing suprasellar calcifications in 64% of cases. The majority of tumors (61%) had developed within the third ventricle (3V) or had invaded it. The adamantinomatous histological variant was the predominant one (73%). Squamous-papillary CPs occurred only in adults older than 40 years of age (p < 0.001). Strong CP adherences to the hypothalamus were demonstrated in 63% of cases. The infundibulo-tuberal and sellar/suprasellar-3V CP topographies were associated with the highest rates of hypothalamic dysfunction before surgery (p < 0.001), surgical hypothalamic injury (p < 0.001), and severe postoperative morbidity and/or mortality (p = 0.009). Both topographies showed the strongest adherences to the hypothalamus and 3V (p < 0.001).

CONCLUSIONS

Cushing's CP series comprises severely ill patients with tumors in the late stages of progression, with a high rate of tumors developing primarily within the hypothalamus (infundibulo-tuberal CPs) or invading this structure from the sellar/suprasellar regions. Craniopharyngioma topography was the fundamental variable influencing the clinical manifestations, tumor features, and patient outcomes in this series.

Intrachiasmatic craniopharyngioma: Assessment of visual outcome with optical coherence tomography after complete surgical removal

Background:

Optic chiasm invasion by a craniopharyngioma (CP) is exceptional. Surgical treatment of intrachiasmatic CPs associates a high risk of chiasm injury, which should be properly addressed before surgery.

Case Description:

We present a 46-year-old woman admitted to the hospital with low visual acuity (0.1 in the right eye and 0.5 in the left) and a severe defect in her visual fields, in addition to headaches, diabetes insipidus, and a long-term depressive disorder. Her visual deficit progressed from a right homonymous temporal inferior quadrantanopia to an almost complete loss of vision in both eyes that only spared the upper nasal quadrants. Brain MRI showed a rounded third ventricle tumor with a potbelly expansion of the optic chiasm, suggesting chiasm invasion by the tumor. Optical coherence tomography (OCT) showed the thinning of the retinal nerve fiber layer (RNFL) in the superior and temporal wedges of the right eye and in the temporal wedge of the left one. The tumor was completely removed by employing a frontotemporal craniotomy and a translamina terminalis approach. Histological analysis showed a squamous-papillary CP. Postoperatively, a significant worsening of the visual defect was evidenced on the perimetry, which was related to a marked RNFL atrophy measured with OCT, as compared to the preoperative study. The poor long-term visual outcome in this patient correlated well with the results of postoperative OCT.

Conclusions:

Preoperative analysis of retinal atrophy with optic coherence tomography allows a reliable assessment of the patient's visual outcome in CPs involving the optic chiasm.

Cystic tumors of the pituitary infundibulum: seminal autopsy specimens (1899 to 1904) that allowed clinical-pathological craniopharyngioma characterization

A heterogeneous group of epithelial cystic tumors developed at the infundibulum and the third ventricle disconcerted pathologists at the dawn of the twentieth century. Very little was known at that time about the physiological role played by the pituitary gland, and there was almost complete ignorance regarding the function of the hypothalamus. Acromegaly, or enlargement of acral body parts, described in 1886 by Pierre Marie, was the only disease linked to primary hypertrophies of the pituitary gland, known as "pituitary strumas". A growing number of young patients manifesting an unexplained combination of physical and mental symptoms, including absent or delayed sexual maturation, progressive obesity, abnormal somnolence, and dementia-like changes in behavior were reported to present large solid-cystic tumors which characteristically expanded within the infundibulum and third ventricle, above an anatomically intact pituitary gland. Between 1899 and 1904, five seminal autopsy studies from different countries thoroughly described the anatomical relationships and histological features of this newly recognized type of infundibular tumors. These cases were instrumental in fostering the systematic investigation of similar lesions by the Austrian pathologist Jakob Erdheim (1874-1937), who in 1904 was able to classify these infundibulo-tuberal cysts under the common category of hypophyseal duct tumors. The pioneering American neurosurgeon Harvey Cushing (1869-1939) unsuccessfully attempted to surgically remove one of these cysts, for the first time in history, in 1902. The term "craniopharyngioma", chosen by Cushing in 1929 to designate these lesions, would eventually prevail over Erdheim's more accurate denomination, which linked their origin to squamous cell remnants derived from the embryological structures that give rise to the pituitary gland. This paper presents a comprehensive, renewed account of the five clinical-pathological reports which laid the groundwork for the proper clinical diagnosis, topographic conceptualization and pathological categorization of craniopharyngiomas.

Can tissue biomarkers reliably predict the biological behavior of craniopharyngiomas? A comprehensive overview

BACKGROUND

The growing interest in the molecular and genetic alterations of craniopharyngiomas (CPs) is embodied in recent studies revealing insights into the CP tumorigenesis and identifying novel molecular pathways amenable of targeted therapies. The actual impact of this new information, however, remains inconclusive.

METHODS

We present a comprehensive review of the accumulated knowledge on molecular biology of CPs and a critical analysis on the strengths and weaknesses of the studies focused on CP molecular/genetic alterations published to date.

RESULTS

A thorough analysis of the alterations of β-catenin/CTNNB1 and BRAF genes investigated in 1123 CP cases included in 27 studies, showed that, on average, CTNNB1 mutations were present in two-thirds of adamantinomatous CPs and BRAF mutations in 90% of papillary CPs. Their role as oncogenic drivers has not been well established. Although rare, coexistence of both mutations may occur. The involvement of pituitary stem cells in human CP tumorigenesis is still uncertain. Expression of stem markers in human CP samples predominantly occurred along the CP border in contact with brain tissue. Finally, none of the various molecular alterations which have been proposed as markers for CP recurrence can be used today as reliable predictors of the CP behavior.

CONCLUSIONS

The isolated evaluation of CPs' molecular or genetic profiles that do not take into consideration fundamental pathological and therapeutic factors, specifically the tumor topography and the degree of tumor removal, may actually generate confusion regarding the reliability of some biomarkers to predict the CP biological behavior.

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.

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.

Topographic Diagnosis of Craniopharyngiomas: The Accuracy of MRI Findings Observed on Conventional T1 and T2 Images

BACKGROUND AND PURPOSE

The topography of craniopharyngiomas has proved fundamental in predicting the involvement of vital brain structures and the possibility of achieving a safe radical resection. Beyond the imprecise term "suprasellar," indiscriminately used for craniopharyngiomas, an accurate definition of craniopharyngioma topography should be assessed by preoperative MR imaging. The objective of this study was to investigate the MRI findings that help define craniopharyngioma topography.

MATERIALS AND METHODS

This study retrospectively investigated a cohort of 200 surgically treated craniopharyngiomas with their corresponding preoperative midsagittal and coronal conventional T1- and T2-weighted MR images, along with detailed descriptions of the surgical findings. Radiologic variables related to the occupation of the tumor of intracranial compartments and the distortions of anatomic structures along the sella turcica-third ventricle axis were analyzed and correlated with the definitive craniopharyngioma topography observed during the surgical procedures. A predictive model for craniopharyngioma topography was generated by multivariate analysis.

RESULTS

Five major craniopharyngioma topographies can be defined according to the degree of hypothalamic distortion caused by the tumor: sellar-suprasellar, pseudointraventricular, secondary intraventricular, not strictly intraventricular, and strictly intraventricular. Seven key radiologic variables identified on preoperative MRI allowed a correct overall prediction of craniopharyngioma topography in 86% of cases: 1) third ventricle occupation, 2) pituitary stalk distortion, 3) relative level of the hypothalamus in relation to the tumor, 4) chiasmatic cistern occupation, 5) mammillary body angle, 6) type of chiasm distortion, and 7) tumor shape.

CONCLUSIONS

Systematic assessment of these 7 variables on conventional preoperative T1 and T2 MRI is a useful and reliable method to ascertain individual craniopharyngioma topography.

Jean Camus and Gustave Roussy: pioneering French researchers on the endocrine functions of the hypothalamus

At the beginning of the twentieth century, the hypothalamus was known merely as an anatomical region of the brain lying beneath the thalamus. An increasing number of clinicopathological reports had shown the association of diabetes insipidus and adiposogenital dystrophy (Babinski-Fröhlich's syndrome), with pituitary tumors involving the infundibulum and tuber cinereum, two structures of the basal hypothalamus. The French physicians Jean Camus (1872-1924) and Gustave Roussy (1874-1948) were the first authors to undertake systematic, controlled observations of the effects of localized injuries to the basal hypothalamus in dogs and cats by pricking the infundibulo-tuberal region (ITR) with a heated needle. Their series of surgical procedures, performed between 1913 and 1922, allowed them to claim that both permanent polyuria and adiposogenital dystrophy were symptoms caused by damage to the ITR. Their results challenged the dominant doctrine of hypopituitarism as cause of diabetes insipidus and adiposogenital dystrophy that derived from the experiments performed by Paulescu and Cushing a decade earlier. With their pioneering research, Camus and Roussy influenced the experimental work on the hypothalamus performed by Percival Bailey and Frederic Bremer at Cushing's laboratory, confirming the hypothalamic origin of these symptoms in 1921. More importantly, they provided the foundations for the physiological paradigm of Neuroendocrinology, the hypothalamus' control over the endocrine secretions of the pituitary gland, as well as over water balance and fat metabolism. This article aims to credit Camus and Roussy for their groundbreaking, decisive contributions to postulate the hypothalamus being the brain region in control of endocrine homeostasis and energy metabolism.