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

Applying the en-bloc technique in corpus callosum glioblastoma surgery contributes to maximal resection and better prognosis: a retrospective study

BACKGROUND

Corpus callosum glioblastoma (ccGBM) is a specific type of GBM and has worse outcomes than other non-ccGBMs. We sought to identify whether en-bloc resection of ccGBMs based on T2-FLAIR imaging contributes to clinical outcomes and can achieve a satisfactory balance between maximal resection and preservation of neurological function.

METHODS

A total of 106 adult ccGBM patients (including astrocytoma, WHO grade 4, IDH mutation, and glioblastoma) were obtained from the Department of Neurosurgery in Nanfang Hospital between January 2008 and December 2018. The clinical data, including gender, age, symptoms, location of tumor, involvement of eloquent areas, extent of resection (EOR), pre- and postoperative Karnofsky Performance Status (KPS) scales, and National Institute of Health stroke scale (NIHSS) scores were collected. Propensity score matching (PSM) analysis was applied to control the confounders for analyzing the relationship between the en-bloc technique and EOR, and the change in the postoperative KPS scales and NIHSS scores.

RESULTS

Applying the en-bloc technique did not negatively affect the postoperative KPS scales compared to no-en-bloc resection (P = 0.851 for PSM analysis) but had a positive effect on preserving or improving the postoperative NIHSS scores (P = 0.004 for PSM analysis). A positive correlation between EOR and the en-bloc technique was identified (r = 0.483, P < 0.001; r = 0.720, P < 0.001 for PSM analysis), indicating that applying the en-bloc technique could contribute to enlarged maximal resection. Further survival analysis confirmed that applying the en-bloc technique and achieving supramaximal resection could significantly prolong OS and PFS, and multivariate analysis suggested that tumor location, pathology, EOR and the en-bloc technique could be regarded as independent prognostic indicators for OS in patients with ccGBMs, and pathology, EOR and the en-bloc technique were independently correlated with patient's PFS. Interestingly, the en-bloc technique also provided a marked reduction in the risk of tumor recurrence compared with the no-en-bloc technique in tumors undergoing TR, indicating that the essential role of the en-bloc technique in ccGBM surgery (HR: 0.712; 95% CI: 0.535-0.947; P = 0.02).

CONCLUSIONS

The en-bloc technique could contribute to achieving an enlarged maximal resection and could significantly prolong overall survival and progression-free survival in patients with ccGBMs.

Endoscopic Endonasal Transtuberculum Approach for Pediatric Tuberoinfundibular Craniopharyngioma: 2-Dimensional Operative Video

INDICATIONS CORRIDOR AND LIMITS OF EXPOSURE

The endoscopic endonasal transtuberculum approach grants access to suprasellar and retrochiasmatic lesions with hypothalamic involvement. Here, we present a case of a 13-year-old boy with a history of stunted growth, decreased vision, headaches, and low energy with a tuberoinfundibular craniopharyngioma. The patient consented to the procedure.

ANATOMIC ESSENTIALS NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT

Evaluation of the sphenoid sinus pneumatization, internal carotid artery disposition, presence of clinoidal rings, variations of the infrachiasmatic corridor (optic chiasm location, height of dorsum sella), and location of the pituitary stalk are crucial for surgical strategy.

ESSENTIALS STEPS OF THE PROCEDURE

Harvesting of nasoseptal flap and access to the sphenoid sinus; drilling the sella, tuberculum, and chiasmatic sulcus up to the limbus sphenoidalis and laterally exposing the clinoidal carotid artery segment; wide dural opening to the level of distal rings inferolaterally and falciform ligaments superolaterally; identification and coagulation of superior hypophyseal branches providing tumor supply; intracapsular dissection and debulking and subpial sharp dissection at the hypothalamic tumor interface to achieve complete removal; and reconstruction with inlay collagen, fascia lata, and nasoseptal flap.

PITFALLS/AVOIDANCE OF COMPLICATIONS

Preservation of the superior hypophyseal arteries and stalk is essential for preventing pituitary dysfunction. Preoperative reckoning of hypothalamic invasion and identification of adequate interface aids in avoiding complications. To reduce CSF leak risk, multilayer reconstruction was performed and lumbar drain placed postoperatively.

VARIANTS AND INDICATIONS FOR THEIR USE

For retroclival extension, intradural pituitary transposition should be considered to expand the corridor; in patients with preoperative hypopituitarism, pituitary sacrifice is most effective to increase retroclival access.

Contemporary Biological Insights and Clinical Management of Craniopharyngioma

Craniopharyngiomas (CPs) are clinically aggressive tumors because of their invasive behavior and recalcitrant tendency to recur after therapy. There are 2 types based on their distinct histology and molecular features: the papillary craniopharyngioma (PCP), which is associated with BRAF-V600E mutations and the adamantinomatous craniopharyngioma (ACP), characterized by mutations in CTNNB1 (encoding β-catenin). Patients with craniopharyngioma show symptoms linked to the location of the tumor close to the optic pathways, hypothalamus, and pituitary gland, such as increased intracranial pressure, endocrine deficiencies, and visual defects. Treatment is not specific and mostly noncurative, and frequently includes surgery, which may achieve gross total or partial resection, followed by radiotherapy. In cystic tumors, frequent drainage is often required and intracystic instillation of drugs has been used to help manage cyst refilling. More recently targeted therapies have been used, particularly in PCP, but also now in ACP and clinical trials are underway or in development. Although patient survival is high, the consequences of the tumor and its treatment can lead to severe comorbidities resulting in poor quality of life, in particular for those patients who bear tumors with hypothalamic involvement. Accordingly, in these patients at risk for the development of a hypothalamic syndrome, hypothalamus-sparing treatment strategies such as limited resection followed by irradiation are recommended. In this review, we provide an update on various aspects of CP, with emphasis on recent advances in the understanding of tumor pathogenesis, clinical consequences, management, and therapies.

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.

Endoscopic endonasal approach for infradiaphragmatic craniopharyngiomas: a multicentric Italian study

OBJECTIVE

Infradiaphragmatic craniopharyngiomas (ICs) represent a distinct subtype, harboring a sellar-suprasellar origin and generally growing in the extra-arachnoidal space contained by the diaphragma sellae. They have been considered ideal for surgical removal through the transsphenoidal approach since the 1960s. The authors present a multicentric national study, intending to selectively analyze IC behavior and the impact of the transsphenoidal endoscopic endonasal approach (EEA) on surgical outcomes.

METHODS

Craniopharyngiomas that were intraoperatively recognized as infradiaphragmatic and removed with standard EEA between 2000 and 2021 at 6 Italian neurosurgical departments were included in the study. Clinical, radiological, and surgical findings and outcomes were evaluated and reviewed.

RESULTS

In total, 84 patients were included, with 45.23% identified as pediatric cases and 39.28% as having recurrent tumors. The most common presenting symptoms were endocrine (75%), visual (59.52%), and hypothalamic (26.19%) disorders. ICs were classified as extending below (6 intrasellar and 41 occupying the suprasellar cistern) or above (26 obliterating the anterior recesses of the third ventricle and 11 extending up to the foramina of Monro) the chiasmatic cistern. Gross-total resection (GTR) was achieved in 54 cases (64.28%). Tumor extension above the chiasmatic cistern and calcifications were associated with lower likelihood of GTR. The cumulative rate of postoperative complications was 34.53%, with CSF leak being the most common (14.28%). Endocrine, visual, and hypothalamic functions deteriorated postoperatively in 41/78 patients (52.56%), 5/84 (5.95%), and 14/84 (16.67%), respectively. Twenty-eight patients (33.33%) had recurrence during follow-up (mean 63.51 months), with a mean 5-year progression-free survival (PFS) rate of 58%. PFS was greater in patients who achieved GTR than patients with other extent of resection.

CONCLUSIONS

This is the largest series in the literature to describe ICs removed with standard EEA, without the need for additional bone and dural opening over the planum sphenoidale. EEA provides a direct route to ICs, the opportunity to manage lesions extending up to the third ventricle without breaching the diaphragma, and high rates of GTR and satisfactory clinical outcomes. Increased surgical complexity and morbidity should be expected in patients with extensive suprasellar extension and involvement of the surrounding vital neurovascular structures.

Deep-learning-based automatic segmentation and classification for craniopharyngiomas

Objective

Neuronavigation and classification of craniopharyngiomas can guide surgical approaches and prognostic information. The QST classification has been developed according to the origin of craniopharyngiomas; however, accurate preoperative automatic segmentation and the QST classification remain challenging. This study aimed to establish a method to automatically segment multiple structures in MRIs, detect craniopharyngiomas, and design a deep learning model and a diagnostic scale for automatic QST preoperative classification.

Methods

We trained a deep learning network based on sagittal MRI to automatically segment six tissues, including tumors, pituitary gland, sphenoid sinus, brain, superior saddle cistern, and lateral ventricle. A deep learning model with multiple inputs was designed to perform preoperative QST classification. A scale was constructed by screening the images.

Results

The results were calculated based on the fivefold cross-validation method. A total of 133 patients with craniopharyngioma were included, of whom 29 (21.8%) were diagnosed with type Q, 22 (16.5%) with type S and 82 (61.7%) with type T. The automatic segmentation model achieved a tumor segmentation Dice coefficient of 0.951 and a mean tissue segmentation Dice coefficient of 0.8668 for all classes. The automatic classification model and clinical scale achieved accuracies of 0.9098 and 0.8647, respectively, in predicting the QST classification.

Conclusions

The automatic segmentation model can perform accurate multi-structure segmentation based on MRI, which is conducive to clearing tumor location and initiating intraoperative neuronavigation. The proposed automatic classification model and clinical scale based on automatic segmentation results achieve high accuracy in the QST classification, which is conducive to developing surgical plans and predicting patient prognosis.

Socio-behavioral dysfunction in disorders of hypothalamic-pituitary involvement: The potential role of disease-induced oxytocin and vasopressin signaling deficits

Disorders involving hypothalamic and pituitary (HPIT) structures-including craniopharyngioma, Langerhans cell histiocytosis, and intracranial germ cell tumors-can disrupt brain and endocrine function. An area of emerging clinical concern in patients with these disorders is the co-occurring socio-behavioral dysfunction that persists after standard hormone replacement therapy. Although the two neuropeptides most implicated in mammalian social functioning (oxytocin and arginine vasopressin) are of hypothalamic origin, little is known about how disease-induced damage to HPIT structures may disrupt neuropeptide signaling and, in turn, impact patients' socio-behavioral functioning. Here we provide a clinical primer on disorders of HPIT involvement and a review of neuropeptide signaling and socio-behavioral functioning in relevant animal models and patient populations. This collective evidence suggests that neuropeptide signaling disruptions contribute to socio-behavioral deficits experienced by patients with disorders of HPIT involvement. A better understanding of the biological underpinnings of patients' socio-behavioral symptoms is now needed to enable the development of the first targeted pharmacological strategies by which to manage patients' socio-behavioral dysfunction.

Adult neurogenesis of the median eminence contributes to structural reconstruction and recovery of body fluid metabolism in hypothalamic self-repair after pituitary stalk lesion

Body fluid homeostasis is critical to survival. The integrity of the hypothalamo-neurohypophysial system (HNS) is an important basis of the precise regulation of body fluid metabolism and arginine vasopressin (AVP) hormone release. Clinically, some patients with central diabetes insipidus (CDI) due to HNS lesions can experience recovery compensation of body fluid metabolism. However, whether the hypothalamus has the potential for structural plasticity and self-repair under pathological conditions remains unclear. Here, we report the repair and reconstruction of a new neurohypophysis-like structure in the hypothalamic median eminence (ME) after pituitary stalk electrical lesion (PEL). We show that activated and proliferating adult neural progenitor cells differentiate into new mature neurons, which then integrate with remodeled AVP fibers to reconstruct the local AVP hormone release neural circuit in the ME after PEL. We found that the transcription factor of NK2 homeobox 1 (NKX2.1) and the sonic hedgehog signaling pathway, mediated by NKX2.1, are the key regulators of adult hypothalamic neurogenesis. Taken together, our study provides evidence that adult ME neurogenesis is involved in the structural reconstruction of the AVP release circuit and eventually restores body fluid metabolic homeostasis during hypothalamic self-repair.

Risk factors for postresection shunting in children with suprasellar tumor: a retrospective analysis of 124 patients

OBJECTIVE

Hydrocephalus is one of the most significant comorbidities of pediatric suprasellar tumors. Up to 37.5-68.0% of patients were diagnosed with hydrocephalus at admission. However, after surgical resection of the tumor, 9.3-51.4% of the hydrocephalus will persist and require a ventriculoperitoneal shunt (VPS) surgery. The purpose of this study was to identify the risk factors associated with postresection shunting in children with suprasellar tumors.

METHODS

We conducted a retrospective analysis of children who underwent surgery for suprasellar tumors at our department from February 2011 to December 2020. We used univariate and multivariate analysis to screen the factors that might be correlated with postoperative shunt placement, taking into account patients' characteristics, tumor histology/size/calcification, the severity of preoperative hydrocephalus, the involvement of ventricles, external ventricular drainage (EVD) placement, postoperative intraventricular hematoma, the extent of resection, and other surgical details.

RESULTS

A total of 124 children who underwent surgery for suprasellar tumors were included in our study. Hydrocephalus was present in 55 patients (44.3%) at admission; 23 patients (18.5%) received VPS implantation after tumor removal. Univariate analysis showed that the involvement of ventricles (p = 0.002), moderate/severe preoperative hydrocephalus (p = 0.001), postoperative intraventricular hematoma (p = 0.005), and EVD implantation (p = 0.001) were significantly associated with postoperative VPS. Multivariate analysis confirmed that only ventricle involvement (p = 0.002; OR = 5.6; 95%CI 1.8-17.2) and intraventricular hematoma (p = 0.01; OR = 10.7; 95%CI 1.8-64.2) were independent risk factors for postresection shunting.

CONCLUSION

Ventricle involvement and intraventricular hematoma can be identified as independent predictors for postoperative shunting in pediatric suprasellar tumors.

Endoscopic Endonasal Transsphenoidal Surgery for Recurrent Craniopharyngiomas

Object

Although revision surgery for recurrent craniopharyngiomas is more challenging than primary surgery and often accompanies a higher risk of death and complications, endoscopic endonasal transsphenoidal surgery (EETS) is sometimes still an effective and reliable treatment option. In this study, we introduced the surgical outcomes of EETS for recurrent craniopharyngiomas and summarized the surgical experiences.

Methods

Between 2014 and 2018, 28 patients with recurrent craniopharyngiomas underwent 29 EETS in our department. We regarded the patient undergoing two EETS as two independent patients in statistical analysis. Of the 29 patients, 16 had undergone 1 previous surgery, 10 had undergone 2 previous surgeries, and the remaining 3 patients had undergone 3 surgeries. The extent of resection, visual and endocrine outcomes, and complications of all the patients were collected and analyzed.

Results

Gross total resection was accomplished in 16 patients (55.17%), subtotal resection in 11 patients (37.93%), and partial resection in 2 patients (6.9%). Among the 22 patients with preoperative visual acuity and visual field impairment, some degree of vision improvement was observed in 18 patients, 3 patients were without visual change, and perpetual deterioration of vision occurred in one patient. The remaining six patients had normal vision before and after surgery. Postoperative endocrine tests showed that, among five patients with normal preoperative pituitary hormone function, only one patient still had normal pituitary hormone function and the other four patients had one or more hypothalamic-pituitary axes involved. None of the patients with preoperative endocrine dysfunction had endocrine function improved. Diabetes insipidus was observed in six new cases postoperatively. Cerebrospinal fluid (CSF) leakage occurred in 1 patient. One patient had bacterial meningitis, which was cured with antibiotics and a lumbar drain. No serious morbidity and mortality occurred in all patients.

Conclusions

For recurrent craniopharyngiomas, a personalized treatment plan should be developed according to the tumor characteristics and the patient's situation. There is no omnipotent method to be used for all patients. The EETS still is a safe and effective way to treat recurrent craniopharyngiomas in appropriate patients.

Endocrine Disorder in Patients With Craniopharyngioma

Craniopharyngioma is an intracranial congenital epithelial tumor growing along the pathway of the embryonic craniopharyngeal tube. The main clinical symptoms of patients with craniopharyngioma include high intracranial pressure, visual field defect, endocrine dysfunction, and hypothalamic dysfunction. At present, the preferred treatment remains the surgical treatment, but the recovery of endocrine and hypothalamic function following surgery is limited. In addition, endocrine disorders often emerge following surgery, which seriously reduces the quality of life of patients after operation. So far, research on craniopharyngioma focuses on ways to ameliorate endocrine dysfunction. This article reviews the latest research progress on pathogenesis, manifestation, significance, and treatment of endocrine disorders in patients with craniopharyngioma.

Comparison of Outcomes following Primary and Repeat Resection of Craniopharyngioma

Introduction The management of recurrent craniopharyngioma is complex with limited data to guide decision-making. Some reports suggest reoperation should be avoided due to an increased complication profile, while others have demonstrated that safe reoperation can be performed. For other types of skull base lesions, maximal safe resection followed by adjuvant therapy has replaced radical gross total resection due to the favorable morbidity profiles.

Methods Seventy-one patients underwent resection over a 9-year period for craniopharyngioma and were retrospectively reviewed. Patients were separated into primary resection and reoperation cohorts and stratified by surgical approach (endonasal vs. cranial) and survival analyses were performed based on cohort and surgical approach.

Results Fifty patients underwent primary resection, while 21 underwent reoperation for recurrence. Fifty endonasal transsphenoidal surgeries and 21 craniotomies were performed. Surgical approaches were similarly distributed across cohorts. Subtotal resection was achieved in 83% of all cases. There were no differences in extent of resection, visual outcomes, subsequent neuroendocrine function, and complications across cohorts and surgical approaches. The median time to recurrence was 87 months overall, and there were no differences by cohort and approach. The 5-year survival rate was 81.1% after reoperation versus 93.2% after primary resection.

Conclusion Compared with primary resection, reoperation for craniopharyngioma recurrence is associated with similar functional and survival outcomes in light of individualized surgical approaches. Maximal safe resection followed by adjuvant radiotherapy for residual tumor likely preserves vision and endocrine function without sacrificing overall patient survival.

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.

Multifactor Prognostic Evaluation of Postoperative Craniopharyngiomas

PURPOSE

To evaluate various factors that could be associated with the postoperative prognosis of patients with craniopharyngiomas and provide evidence for the proper surgical course and optimal outcome assessments of craniopharyngiomas.

METHODS

We performed a retrospective study and reviewed 68 patients with craniopharyngiomas who received surgery from May 2013 to October 2018. The relationships between the disease prognosis and age, gender, onset symptoms, size of tumor, degree of calcification, consistency, QST classification, adhesion strength, and pathological types were analyzed.

RESULTS

There were no significant associations between the prognosis and age, gender, number of onset symptoms, and pathological types (P > 0.05). The severity of onset symptoms, tumor diameter, and degree of calcification was significantly associated with the prognosis (P < 0.05). There were significant different prognoses between patients with cystic and solid, mixed tumors (P < 0.05). The prognosis of patients with T type tumors was different from that of patients with either Q or S type tumors (P < 0.05). The prognoses of patients with either loose or tight type tumors were significantly different from those of patients with either invasive or fusion type tumors (P < 0.05).

CONCLUSION

Clinical and pathological variables, such as onset symptoms, size of tumor, degree of calcification, consistency, QST classification, and the degree of adhesion strength, were important factors in evaluating the prognosis of patients with craniopharyngiomas.

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.

Is Low-Lying Optic Chiasm an Obstacle to an Endoscopic Endonasal Approach for Retrochiasmatic Craniopharyngiomas? (Korean Society of Endoscopic Neurosurgery -003)

OBJECTIVE

Despite advances in endoscopic techniques, retrochiasmatic craniopharyngiomas (CPs) are difficult to remove completely, because the low-lying optic chiasm often provides an obstacle to an endoscopic endonasal approach. This study aimed to identify the endoscopic surgical outcomes of the retrochiasmatic CP and resolve the issues related to low-lying optic chiasm.

METHODS

We reviewed 154 consecutive patients with CP who underwent endonasal endoscopic resection from February 2009 to April 2017 at 2 independent institutions. The topographic relationship of the tumor with the third ventricle, stalk, and optic chiasm and clinical outcomes were investigated.

RESULTS

Retrochiasmatic CPs were found in 142 of 154 patients (92.2%). The median follow-up time was 25 months. Gross total resection and near-total resection were achieved in 113 patients (79.6%) and 21 patients (13.8%), respectively. Postoperative cerebrospinal fluid leaks were found in 16 patients (11.3%). Low-lying and high-lying chiasms were found in 44 patients (31.0%) and 98 patients (69.0%), respectively. Low-lying chiasm did not affect clinical outcomes including the extent of resection. Patients with low-lying chiasm showed a marginal trend for postoperative visual deterioration. The ventricular growth pattern representing the origin of the tumor and previous surgery were significantly associated with the position of the optic chiasm (P = 0.007 and 0.001, respectively).

CONCLUSIONS

An endoscopic endonasal approach is an effective surgical approach for retrochiasmatic CP, even in tumors with low-lying chiasm. However, a thorough and careful dissection is necessary to prevent visual deterioration.