The therapeutic efficacy of fractionated radiotherapy and gamma-knife radiosurgery for craniopharyngiomas

Enhanced outcomes in residual or recurrent craniopharyngioma: evaluating combined gamma knife and phosphorus-32 brachytherapy

BACKGROUND

Managing residual and recurrent craniopharyngioma effectively is crucial for improving patient outcomes. This study evaluates the combined use of gamma knife and phosphorus-32 brachytherapy, offering insights into alternative, less invasive treatment strategies.

METHODS

We conducted a retrospective analysis of 97 patients treated from 2010 to 2016 for residual and recurrent craniopharyngioma using gamma knife and phosphorus-32 brachytherapy. We classified these patients into three groups: superficial solid (Group A), simple cystic (Group B), and mixed cystic-solid (Group C). We assessed the treatment's effectiveness by the tumor control rates and evaluated safety by monitoring vision, endocrine function improvements, and complication rates.

RESULTS

The treatment achieved complete and adequate control rates of 49.5% and 87.6%, respectively. We observed improvements in vision or visual fields in 55.1% of the patients. The morbidity rate was 15.5%. The study found no significant differences in tumor control rates among the various lesion types.

CONCLUSION

The combination of gamma knife and phosphorus-32 brachytherapy presents a viable, minimally invasive alternative for treating residual and recurrent craniopharyngioma. It offers high tumor control and functional improvement rates, suggesting its potential as a preferred strategy in some instances.

Craniopharyngioma in Pediatrics and Adults

Craniopharyngiomas are rare malignancies of dysembryogenic origin, involving the sellar and parasellar areas. These low-grade, epithelial tumors account for two main histological patterns (adamantinomatous craniopharyngioma and papillary craniopharyngioma), which differ in epidemiology, pathogenesis, and histomorphological appearance. Adamantinomatous craniopharyngiomas typically show a bimodal age distribution (5-15 years and 45-60 years), while papillary craniopharyngiomas are limited to adult patients, especially in the fifth and sixth decades of life. Recently, craniopharyngioma histological subtypes have been demonstrated to harbor distinct biomolecular signatures. Somatic mutations in CTNNB1 gene encoding β-catenin have been exclusively detected in adamantinomatous craniopharyngiomas, which predominantly manifest as cystic lesions, while papillary craniopharyngiomas are driven by BRAF V600E mutations in up to 95% of cases and are typically solid masses. Despite the benign histological nature (grade I according to the World Health Organization classification), craniopharyngiomas may heavily affect long-term survival and quality of life, due to their growth pattern in a critical region for the presence of eloquent neurovascular structures and possible neurological sequelae following their treatment. Clinical manifestations are mostly related to the involvement of hypothalamic-pituitary axis, optic pathways, ventricular system, and major blood vessels of the circle of Willis. Symptoms and signs referable to intracranial hypertension, visual disturbance, and endocrine deficiencies should promptly raise the clinical suspicion for sellar and suprasellar pathologies, advocating further neuroimaging investigations, especially brain MRI. The optimal therapeutic management of craniopharyngiomas is still a matter of debate. Over the last decades, the surgical strategy for craniopharyngiomas, especially in younger patients, has shifted from the aggressive attempt of radical resection to a more conservative and individualized approach via a planned subtotal resection followed by adjuvant radiotherapy, aimed at preserving functional outcomes and minimizing surgery-related morbidity. Whenever gross total removal is not safely feasible, adjuvant radiotherapy (RT) and stereotactic radiosurgery (SRS) have gained an increasingly important role to manage tumor residual or recurrence. The role of intracavitary therapies, including antineoplastic drugs or sealed radioactive sources, is predominantly limited to monocystic craniopharyngiomas as secondary therapeutic option. Novel findings in genetic profiling of craniopharyngiomas have unfold new scenarios in the development of targeted therapies based on brand-new biomolecular markers, advancing the hypothesis of introducing neoadjuvant chemotherapy regimens in order to reduce tumor burden prior to resection. Indeed, the rarity of these neoplasms requires a multispecialty approach involving an expert team of endocrinologists, neurosurgeons, neuro-ophthalmologists, neuroradiologists, radiotherapists, and neuro-oncologists, in order to pursue a significant impact on postoperative outcomes and long-term prognosis.

Current Advances in the Management of Adult Craniopharyngiomas

Craniopharyngiomas (CPs) are slow growing, histologically benign intracranial tumors located in the sellar–suprasellar region. Although known to have low mortality, their location and relationship to the adjacent neural structures results in patients having significant neurologic, endocrine, and visual comorbidities. The invasive nature of this tumor makes complete resection a challenge and contributes to its recurrence. Additionally, these tumors are bimodally distributed, being treated with surgery, and are followed by other adjuncts, such as focused radiation therapy, e.g., Gamma knife. Advances in surgical techniques, imaging tools, and instrumentations have resulted in the evolution of surgery using endoscopic techniques, with residual components being treated by radiotherapy to target the residual tumor. Advances in molecular biology have elucidated the main pathways involved in tumor development and recurrence, but presently, no other treatments are offered to patients, besides surgery, radiation, and endocrine management, as the disease and tumor evolve. We review the contemporary management of these tumors, from the evolution of surgical treatments, utilizing standard open microscopic approaches to the more recent endoscopic surgery, and discuss the current recommendations for care of these patients. We discuss the developments in radiation therapy, such as radiosurgery, being used as treatment strategies for craniopharyngioma, highlighting their beneficial effects on tumor resections while decreasing the rates of adverse outcomes. We also outline the recent chemotherapy modalities, which help control tumor growth, and the immune landscape on craniopharyngiomas that allow the development of novel immunotherapies.

Comparison between extended transsphenoidal and transcranial surgery for craniopharyngioma: focus on hypothalamic function and obesity

PURPOSE

Patients suffering from craniopharyngiomas currently have good survival rates, but long-term sequelae, such as development of obesity, worsen their quality of life. Optimal treatment is still controversial and changed during the decades, becoming less aggressive. Transcranial (TC) surgery was the first approach to be used, followed by extended transsphenoidal (eTNS) access. This study aims to compare the two approaches in terms of risk of hypothalamic damage leading to obesity.

METHODS

This is a monocentric retrospective analysis of post-puberal patients treated for primary craniopharyngioma. Postoperative obesity and percentual postsurgical BMI variation were considered proxy for hypothalamic function and used to fit regression models with basal BMI, type of surgery, tumor volume and hypothalamic involvement (anterior vs. anteroposterior).

RESULTS

No difference in radicality was observed between the two approaches; eTNS was more effective in ameliorating visual function but was significantly associated with CSF leaks. The TC approach was associated with a higher incidence of diabetes insipidus. Regression analysis showed only tumor volume and basal BMI resulted as independent predictors for both postoperative obesity (respectively, OR 1.15, P = 0.041, and OR 1.57, P < 0.001) and percentual BMI variation (respectively, + 0.92%, P = 0.005, and - 1.49%, P = 0.001).

CONCLUSIONS

Larger lesions portend a higher risk to develop postoperative obesity, independently of hypothalamic involvement. Interestingly, basal BMI is independent of lesional volume and is associated with postoperative obesity, but lesser postoperative BMI variation. The surgical approach does not influence the obesity risk. However, eTNS proves valid in managing large tumors with important hypothalamic invasion.

Craniopharyngiomas: Surgery and Radiotherapy

Taking into account the benign nature of craniopharyngiomas, the main method of treatment is the resection of the tumor. However, the tendency of these tumors to invade critical structures (such as optic pathways, the hypothalamic-pituitary system, the Willis circle vessels) often limits the possibility of a radical surgery.Craniopharyngiomas of the third ventricle represent the greatest challenge for surgery. After radical surgery, hypothalamic disorders often occur, including not only obesity but also cognitive, emotional, mental, and metabolic disturbances. Metabolic disorders associated with damage to the hypothalamus progress after surgery and lead to impaired functions of the internal organs. This process is irreversible and, in many cases, becomes the direct cause of mortality. The life expectancy of patients with the surgically affected hypothalamus is significantly shorter than in patients with preserved diencephalic function. The incidence of hypothalamic disorders after surgery can reach 40%.Even with macroscopically total resection, craniopharyngiomas can recur in 10-30% of cases, and in the presence of tumor remnants and with no further radiation treatment, the risk of recurrence significantly increases to up to 50-85% according to various studies. For this reason, the observation of patients with residual tumors after surgery is an incorrect strategy.Radiation therapy significantly improves progression-free survival (PFS), and the use of stereotactic irradiation techniques ensures conformity of irradiation of tumor remnants with a complicated shape and location (Iwata H et al., J Neurooncol 106(3):571-577, 2012; Aggarwal et al., Pituitary 16(1):26-33, 2013; Savateev et al., Zh Vopr Neirokhir Im N N Burdenko 81(3):94-106; 2017), which potentially reduces the risk of undesirable postradiation effects. Therefore, the quality of life in patients with craniopharyngiomas infiltrating the hypothalamus is significantly higher after non-radical operations with subsequent stereotactic radiation than after a total or subtotal removal.

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.

A regional Australasian experience of extended endoscopic transsphenoidal surgery for craniopharyngioma: Progression of the mentoring model

Endoscopic endonasal transsphenoidal approaches to craniopharyngioma has become increasingly popular over the last 15 years. We present the results of our retrospective series of craniopharyngiomata resected by an endoscopic, endonasal approach at a low-volume service in Australasia. Between the years of 2009 and 2017, 11 patients underwent pure endoscopic endonasal transsphenoidal resection for a craniopharyngioma at our institutions. The medical records, histopathology, intraoperative findings and patient imaging were retrospectively assessed. 11 patients were included with 5 male and 6 female patients. The mean age was 32.0 years (range 14-68 years). Of this patient series a gross total resection of the tumour was achieved in 8 of 11 patients (73%). In the immediate postoperative phase, 10 of the 11 patients developed diabetes insipidus (91%). The pituitary stalk was formally not seen in 4 patients and all were treated with vasopressin. Of the 7 patients where the pituitary stalk was identified it was formally divided in 6 and preserved in 1 patient where the tumour was separate to the stalk. The endoscopic endonasal transsphenoidal approach for excision of craniopharyngioma, utilising and progressing the surgical mentoring model, can achieve adequate decompression of critical structures. Furthermore, our aggressive approach to divide and remove the involved pituitary stalk results in high rates of gross macroscopic resection with excellent long-term disease control with a greater risk of postoperative diabetes insipidus and panhypopituitarism.

Radiotherapy Advances in Pediatric Neuro-Oncology

Radiation therapy (RT) represents an integral component in the treatment of many pediatric brain tumors. Multiple advances have emerged within pediatric radiation oncology that aim to optimize the therapeutic ratio—improving disease control while limiting RT-related toxicity. These include innovations in treatment planning with magnetic resonance imaging (MRI) simulation, as well as increasingly sophisticated radiation delivery techniques. Advanced RT techniques, including photon-based RT such as intensity-modulated RT (IMRT) and volumetric-modulated arc therapy (VMAT), as well as particle beam therapy and stereotactic RT, have afforded an array of options to dramatically reduce radiation exposure of uninvolved normal tissues while treating target volumes. Along with advances in image guidance of radiation treatments, novel RT approaches are being implemented in ongoing and future prospective clinical trials. As the era of molecular risk stratification unfolds, personalization of radiation dose, target, and technique holds the promise to meaningfully improve outcomes for pediatric neuro-oncology patients.

[Radiotherapy and radiosurgery in treatment of craniopharyngiomas]

Craniopharyngiomas are benign epithelial tumors having a dysembryogenetic origin, which are usually located in the sellar/parasellar and/or third ventricle regions. Gross total resection is the modern standard of treatment for these tumors because of a low recurrence rate. However, this surgery in some patients with craniopharyngioma often leads to the development or worsening of diencephalic disorders poorly responding to treatment. Perhaps, in these cases, subtotal or partial tumor resection or implantation of an Ommaya reservoir into the tumor cyst followed by stereotactic radiotherapy/radiosurgery may provide better functional outcomes and higher life quality in patients, with tumor growth control being reasonable (according to the published data, the mean 10-year disease-free survival is 66.9% after total tumor resection and 79.6% after combined treatment). The paper presents a review of the literature on radiological treatment of craniopharyngiomas. We discuss the issues of indications, optimal timing of radiotherapy/radiosurgery, its efficacy, and treatment outcomes in terms of complications and quality of life. Particular attention is paid to enlargement of craniopharyngioma cysts during and after radiological treatment.

Endoscopic Endonasal Management of Craniopharyngioma

Craniopharyngioma is a rare clinical entity that poses a significant management challenge given their location and propensity to recur. As part of a minimally disruptive treatment paradigm, the expanded endonasal approach has the potential to improve rates of resection, improve postoperative visual recovery, and minimize surgical morbidity. This article updates the otolaryngologic community on the basic principles and techniques regarding the incorporation of the endoscopic, endonasal approach in the management paradigm of craniopharyngioma.

High FABP5 Versus CRABPII Expression Ratio in Recurrent Craniopharyngiomas: Implications for Future Treatment

BACKGROUND AND OBJECTIVE

Recurrence is a major problem in craniopharyngioma (CP) management. Recent study shows that high FABP5/CRABPII may be related to tumor growth and that all-trans retinoic acid (ATRA) may suppress primary CP growth. We studied the expression profile of FABP5 and CRABPII in recurrent CP tissue and the effect of ATRA on recurrent CP cells.

METHODS

Fifty cases of patients with CP were enrolled in the retrospective study. Among them, 15 were recurrent. Fresh specimens were collected for immunohistochemistry, reverse transcription polymerase chain reaction, and western blotting analysis of FABP5 and CRABPII. Fresh specimens from 6 primary and recurrent CPs were collected and subjected to cell culture using an explants method. ATRA at various concentrations was applied to recurrent CP cell culture, and cell growth was recorded and analyzed.

RESULTS

Immunohistochemistry, reverse transcription polymerase chain reaction, and western blot study showed that FABP5 was expressed significantly higher in recurrent tumors, whereas CRABPII was expressed significantly higher in primary tumors. The FABP5/CRABPII ratio was significantly higher in recurrent rather than primary tumors. Recurrent CP cells grew faster than primary cells, and ATRA induced cellular apoptosis and inhibited CP cell growth in a dose-dependent manner.

CONCLUSIONS

A high expression ratio between FABP5 and CRABPII may be related to CP tumor recurrence and ATRA could be a potential therapeutic agent for CP chemotherapy.

Radiosurgery for Pediatric Brain Tumors

The utility of radiosurgery for pediatric brain tumors is not well known. For children, radiosurgery may have an important role for treating unresectable tumors, residual disease, or tumors in the recurrent setting that have received prior radiotherapy. The available evidence demonstrates utility for some children with primary brain tumors resulting in good local control. Radiosurgery can be considered for limited residual disease or focal recurrences. However, the potential toxicities are unique and not insignificant. Therefore, prospective studies need to be performed to develop guidelines for indications and treatment for children and reduce toxicity in this population.

Recurrent craniopharyngioma after conformal radiation in children and the burden of treatment

OBJECT

In this paper the authors present their experience treating children with recurrent craniopharyngioma who were initially managed with surgery followed by conformal radiation therapy (CRT).

METHODS

A departmental oncology information system was queried to identify all children (< 18 years old) who received CRT for a craniopharyngioma between 1998 and 2010 (inclusive) and specifically those who experienced tumor progression. For each patient, the authors recorded the type of recurrence (solid, cystic, or both), the time interval to first progression and each subsequent progression, the associated treatment complications, and disease status at last follow-up evaluation.

RESULTS

Among the 97 patients that met criteria for entry into this study, 18 (18.6%) experienced tumor progression (9 cystic, 3 solid, 6 cystic and solid). The median time to first recurrence was 4.62 years (range 1.81-9.11 years). The subgroup included 6 female and 12 male patients with a median age of 7.54 years (range 3.61-13.83 years). Ten patients experienced first progression within 5 years of CRT. The 5- and 10-year treatment-free survival rates for the entire cohort were 89.0% (95% confidence interval [CI] 80.5%-93.9%) and 76.2% (95% CI 64%-85%), respectively. Seven patients had a single episode of progression and 11 had more than 1. The time interval between each subsequent progression was progressively shorter. The 18 patients underwent 38 procedures. The median follow-up duration for this group was 9.32 years (range 4.04-19.0 years). Three patients died, including 1 from perioperative complications.

CONCLUSIONS

Craniopharyngioma progression after prior irradiation is exceedingly difficult to treat and local control is challenging despite repeated surgical procedures. Given our results, gross-total resection may need to be the surgical goal at the time of first recurrence, if possible. Decompressing new cyst formation alone has a low rate of long-term success.

Gamma Knife surgery for craniopharyngioma: report on a 20-year experience

Object

Although craniopharyngiomas are benign intracranial tumors, their high recurrence rates and intimate associations with surrounding neurovascular structures make gross tumor resection challenging. Stereotactic radiosurgery has been introduced as a valuable adjuvant therapy for recurrent or residual craniopharyngiomas. However, studies with large patient populations documenting long-term survival and progression-free survival rates are rare in the literature. The current study aims to report the long-term radiosurgical results and to define the prognostic factors in a large cohort of patients with a craniopharyngioma.

Methods

A total of 137 consecutive patients who underwent 162 sessions of Gamma Knife surgery (GKS) treatments at the Taipei Veterans General Hospital between 1993 and 2012 were analyzed. The patients' median age was 30.1 years (range 1.5–84.9 years), and the median tumor volume was 5.5 ml (range 0.2–28.4 ml). There were 23 solid (16.8%), 23 cystic (16.8%), and 91 mixed solid and cystic (66.4%) craniopharyngiomas. GKS was indicated for residual or recurrent craniopharyngiomas. The median radiation dose was 12 Gy (range 9.5–16.0 Gy) at a median isodose line of 55% (range 50%–78%).

Results

At a median imaging follow-up of 45.7 months after GKS, the rates of tumor control were 72.7%, 73.9%, and 66.3% for the solid, cystic, and mixed tumors, respectively. The actuarial progression-free survival rates plotted by the Kaplan-Meier method were 70.0% and 43.8% at 5 and 10 years after radiosurgery, respectively. After repeated GKS, the actuarial progression-free survival rates were increased to 77.3% and 61.2% at 5 and 10 years, respectively. The overall survival rates were 91.5% and 83.9% at the 5- and 10-year follow-ups, respectively. Successful GKS treatment can be predicted by tumor volume (p = 0.011). Among the 137 patients who had clinical follow-up, new-onset or worsened pituitary deficiencies were detected in 11 patients (8.0%). Two patients without tumor growth had a worsened visual field, and 1 patient had a new onset of third cranial nerve palsy.

Conclusions

The current study suggests that GKS is a relatively safe modality for the treatment of recurrent or residual craniopharyngiomas, and it is associated with improved tumor control and reduced in-field recurrence rates. Acceptable rates of complications occurred.

National treatment trends, complications, and predictors of in-hospital charges for the surgical management of craniopharyngiomas in adults from 2007 to 2011

Object

Treatment of craniopharyngiomas is one of the most demanding and controversial neurosurgical procedures performed. The authors sought to determine the factors associated with hospital charges and fees for craniopharyngioma treatment to identify possible opportunities for improving the health care economics of inpatient care.

Methods

The authors analyzed the hospital discharge database of the Nationwide Inpatient Sample (NIS) covering the period from 2007 through 2011 to examine national treatment trends for adults (that is, those older than 18 years) who had undergone surgery for craniopharyngioma. To predict the drivers of in-hospital charges, a multistep regression model was developed that accounted for patient demographics, acuity measures, comorbidities, hospital characteristics, and complications.

Results

The analysis included 606 patients who underwent resection of craniopharyngioma; 353 resections involved a transsphenoidal approach (58%) and 253 a transfrontal approach (42%). The mean age (± SD) of patients was 47.7 ± 16.3 years. The average hospital length of stay (LOS) was 7.6 ± 9 days. The mean hospital charge (± SD) was $92,300 ± $83,356. In total, 48% of the patients experienced postoperative diabetes insipidus or an electrolyte abnormality. A multivariate regression model demonstrated that LOS, hospital volume for the selected procedure, the surgical approach, postoperative complications, comorbidities, and year of surgery were all significant predictors of in-hospital charges. The statistical model accounted for 54% of the variance in in-hospital charge.

Conclusions

This analysis of inpatient hospital charges in patients undergoing craniopharyngioma surgery identified key drivers of charges in the perioperative period. Prospective studies designed to evaluate the long-term resource utilization in this complex patient population would be a useful future direction.

[Practice guideline for diagnosis and treatment of craniopharyngioma and parasellar tumors of the pituitary gland]

Craniopharyngiomas are rare, locally aggressive epithelial tumors usually located in the sellar and suprasellar region. Diagnosis of craniopharyngioma is usually suggested by clinical and radiological findings that should be confirmed histologically. Surgery is the treatment of choice for most patients. The goal of surgery is to relieve compressive symptoms and to remove as much tumor as safely possible. Radiation therapy is the usual treatment to control postoperative tumor remnants and local recurrences. Parasellar lesions are low prevalent lesions and include neoplastic, inflammatory, infectious, developmental, and vascular diseases. Both their diagnosis and treatment depend on the type of lesion.

Incidence, treatment and survival of patients with craniopharyngioma in the surveillance, epidemiology and end results program

Craniopharyngioma is a rare primary central nervous system neoplasm. Our objective was to determine factors associated with incidence, treatment, and survival of craniopharyngiomas in the United States. We used the surveillance, epidemiology and end results program (SEER) database to identify patients who received a diagnosis of craniopharyngioma during 2004-2008. We analyzed clinical and demographic information, including age, race, sex, tumor histology, and treatment. Age-adjusted incidence rates and age, sex, and race-adjusted expected survival rates were calculated. We used Cox proportional hazards models to determine the association between covariates and overall survival. We identified 644 patients with a diagnosis of craniopharyngioma. Black race was associated with an age-adjusted relative risk for craniopharyngioma of 1.26 (95% confidence interval [CI], 0.98-1.59), compared with white race. One- and 3-year survival rates of 91.5% (95% CI, 88.9%-93.5%), and 86.2% (95% CI, 82.7%-89.0%) were observed for the cohort; relative survival rates were 92.1% (95% CI, 89.5%-94.0%) and 87.6% (95% CI, 84.1%-90.4%) for 1- and 3-years, respectively. In the multivariable model, factors associated with prolonged survival included younger age, smaller tumor size, subtotal resection, and radiation therapy. Black race, on the other hand, was associated with worse overall survival in the final model. We demonstrated that >85% of patients survived 3 years after diagnosis and that subtotal resection and radiation therapy were associated with prolonged survival. We also noted a higher incidence rate and worse 1- and 3-year survival rates in the black population. Future investigations should examine these racial disparities and focus on evaluating the efficacy of emerging treatment paradigms.