CyberKnife robotic radiosurgery in the multimodal management of acromegaly patients with invasive macroadenoma: a single center's experience

Cyberknife radio-neurosurgery for secreting pituitary adenomas treated with single fraction radio-neurosurgery: A systematic review and meta-analysis

INTRODUCTION

Stereotactic radiosurgery (SRS) is one of the treatment options for the management of residual or recurrent secreting pituitary adenomas (PA). While the role of radiosurgery (RS) by Gamma Knife (GK) has been clearly established, Cyberknife (CK) RS has been evaluated in fewer series.

MATERIAL AND METHODS

To perform a systematic review of the literature and meta-analysis, with the aim of focusing on the effect of CK RS on secreting PA. Using PRISMA guidelines, we reviewed articles published between January 1994 and January 2024. The inclusion criteria contained: single fraction RS, biochemical remission, tumor control and complication appearance (hypopituitarism).

RESULTS

Were incorporated 8 studies including 152 secreting PA. Vast majority were treated in single fraction 115 (75.6 %), with an overall rate of 59.9 % (p < 0.001). Total remission was encountered in 44/108 patients, for an overall rate of 50.2 % (p < 0.001). Partial remission was inconsistently reported among studies for 25/55 patients, for an overall rate of 38.8 % (p = 0.003). Uncontrolled disease was encountered in 36/108 patients, for an overall rate of 32.7 % (p < 0.001). Tumor control was not separately reported for secreting or non-secreting PA, but attained overall high rates.

CONCLUSION

Single fraction CK radiosurgery is common practice for secreting PA. Our meta-analysis suggests high rates of both total and partial remission (as high as 89 % if both taken together), with a complete remission rate of 50.2 %. These results encourage the use of single fraction CK RS for secreting PA. To reach high rates of biochemical control, high doses of irradiation should be used.

The safety and efficacy of robotic radiosurgery and radiotherapy in the management of skull base tumors: a systematic review and meta-analysis

Stereotactic radiosurgery (SRS) and radiotherapy (SRT) have gained prominence as both adjuvant and primary treatment options for patients with skull base tumors that are either inoperable or present as residual or recurrent lesions post-surgery. The object of the current study is to evaluate the safety and efficacy of robotic-assisted SRS and SRT across various skull base pathologies. The study was conducted under PRISMA guidelines and involved a comprehensive evaluation of databases, including PubMed, Scopus, Embase, Web-of-Science, and the Cochrane Library. The data collection period was extended up to 30 September. Statistical analyses were executed using Comprehensive Meta-Analysis software. Furthermore, Cochran's Q test assessed statistical heterogeneity within the findings. From an initial pool of 1,792 articles, 69 studies were included in the systematic review, with 60 qualifying for meta-analysis, encompassing 3,046 participants. Meta-analysis revealed tumor control rates were significantly enhanced with the use of CyberKnife (95% CI: 0.901-0.928, p < 0.001) and robotic Gamma Knife radiosurgery (GKRS) (95% CI: 0.897-0.959, p < 0.001). Meningiomas and schwannomas exhibited higher treatment responsiveness (ES: 0.960 and 0.949, respectively), whereas chordomas displayed lower responsiveness (ES: 0.743). The overall major adverse event rate was between 5.6% and 8.3% (95% CI: 0.056-0.083, p < 0.001). Adverse events exhibited a higher incidence in patients with adenomas (95% CI: 0.122-0.217, p < 0.001), while they were least prevalent in those with schwannomas (95% CI: 0.019-0.041, p < 0.001). Robotic SRS and SRT, employing both gamma-knife and cyber-knife, have demonstrated promising outcomes characterized by high efficacy and safety in managing various skull base tumors.

Outcomes following CyberKnife robotic radiosurgery for pituitary adenomas-a large single-centre study

Introduction

The role of stereotactic radiosurgery (SRS) in pituitary adenomas (PAs) is evolving especially considering its safety. Existing literature is hampered by limited sample sizes and short-term follow-ups, impeding its preeminence in the clinical and radiological outcomes. We propose a comprehensive, single-centred study to evaluate the outcomes following CyberKnife stereotactic radiosurgery (CK SRS) for PAs in a larger patient population, incorporating meticulous clinical and radiological follow-up.

Methods

This is a retrospective cohort study of 278 cases of PAs that underwent CK SRS from 2013 to 2021. Based on their endocrinology profile, they were classified as functional adenomas (FA) and non-functional adenomas (NFA). We assessed pre and post-CK SRS clinical, visual, hormonal and radiological parameters and the associated toxicity. Where applicable, data were compared using the Independent t-test, chi-square test, Fisher Exact and Mann-Whitney U test. A p-value <0.05 was considered significant.

Results

The median age of the patients was 40.13 ± 12.61 years (111 female and 167 male patients). The median prescribed radiosurgery dose was 25.0 ± 5.0 Gy into 3 or 5 fractions. The median follow-up time was 12 months (IQR 20). Data were grouped into NFA (169, 60.8%) and FA (109, 39.2%). After adjusting for patients lost to follow-up, post-CK SRS visual perimetry improved in 80.4% of patients and tumour size reduced in 78.6% of the study population. Seventeen patients with NFA and nine with FA manifested new-onset hormonal deficiencies. No statistically significant differences were seen in post-CK SRS visual outcomes and hormone deficiency groups.

Conclusion

CK SRS is effective and safe for managing PAs, achieving tumour control and preserving visual function with minimal toxicity. Extended follow-up is needed to evaluate post-SRS toxicity and hypopituitarism.

Promising Outcomes in Acromegaly Patients Receiving CyberKnife Stereotactic Hypofractionated Radiotherapy

BACKGROUND

The primary treatment for patients with acromegaly has traditionally been transsphenoidal surgery, with decreasing reliance on radiotherapy (RT) due to advancements in pharmacotherapy (PT). Despite these advancements, a substantial portion of patients still face persistent acromegaly, necessitating novel treatment approaches. This study investigates the role of CyberKnife Stereotactic Hypofractionated Radiotherapy (CK-HFRT) in persistent acromegaly.

OBJECTIVE

The primary objective was to assess the impact of CK-HFRT on endocrine remission (ER) rates while maintaining acceptable toxicity levels.

METHODS

The study retrospectively analyzed 31 consecutive patients with acromegaly who received CK-HFRT following multiple unsuccessful surgeries and prolonged PT without ER. Various CK-HFRT dose fractionation regimes were administered, and dose volume histograms were evaluated. Tumor control, cured disease (CD), endocrine remission (ER) rates, and overall survival were estimated at a median follow-up of 62 months. Acute and late toxicity, including pituitary insufficiency and radiation-induced optic neuropathy (RION), were also assessed.

RESULTS

At 62 months of follow-up, the study group demonstrated excellent tumor control with 100% nonprogressive adenomas. Endocrine remission was achieved in 86.7% of patients, with a 22.4% CD rate at five years. Pituitary insufficiency occurred in 32.3% of patients, and no cases of RION were reported. The study observed three deaths related to cardiovascular diseases, all in patients receiving PT. Overall survival at five years was 79.2%.

CONCLUSION

CyberKnife stereotactic hypofractionated radiotherapy, as an adjunct to PT, provides a viable treatment option for patients with persistent acromegaly following unsuccessful surgeries. The therapy results in substantial ER rates and tumor control while minimizing the risk of permanent radiation-induced optic neuropathy. However, the decision to administer CK-HFRT should be individualized, considering the patient's overall condition and treatment history.

Efficiency and Safety of CyberKnife Robotic Radiosurgery in the Multimodal Management of Patients with Acromegaly

OBJECTIVE

To analyze, in a cohort of acromegalic patients, the results of the efficiency and safety of radiosurgery (CyberKnife), as well as the prognostic factors associated with disease remission.

MATERIAL AND METHODS

Observational, retrospective, longitudinal, and analytical study that included acromegalic patients with persistent biochemical activity after initial medical-surgical treatment, who received treatment with CyberKnife radiosurgery. GH and IGF-1 levels at baseline after one year and at the end of follow-up were evaluated.

RESULTS

57 patients were included, with a median follow-up of four years (IQR, 2-7.2 years). The biochemical remission rate was 45.6%, 33.33% achieved biochemical control, and 12.28% attained biochemical cure at the end of follow-up. A progressive and statistically significant decrease was observed in the comparison of the concentrations of IGF-1, IFG-1 x ULN, and baseline GH at one year and at the end of follow-up. Both cavernous sinus invasion and elevated baseline IGF-1 x ULN concentrations were associated with an increased risk of biochemical non-remission.

CONCLUSION

Radiosurgery (CyberKnife) is a safe and effective technique in the adjuvant treatment of GH-producing tumors. Elevated levels of IGF x ULN before radiosurgery and invasion of the cavernous sinus by the tumor could be predictors of biochemical non-remission of acromegaly.

Stereotactic radiosurgery for secretory pituitary adenomas: systematic review and International Stereotactic Radiosurgery Society practice recommendations

OBJECTIVE

A systematic review was performed to provide objective evidence on the use of stereotactic radiosurgery (SRS) in the management of secretory pituitary adenomas and develop consensus recommendations.

METHODS

The authors performed a systematic review of the English-language literature up until June 2018 using the PRISMA guidelines. The PubMed (Medline), Embase, and Cochrane databases were searched. A total of 45 articles reporting single-institution outcomes of SRS for acromegaly, Cushing's disease, and prolactinomas were selected and included in the analysis.

RESULTS

For acromegaly, random effects meta-analysis estimates for crude tumor control rate, crude endocrine remission rate, and any new hypopituitarism rates were 97.0% (95% CI 96.0%-98.0%), 44.0% (95% CI 35.0%-53.0%), and 17.0% (95% CI 13.0%-23.0%), respectively. For Cushing's disease, random effects estimates for crude tumor control rate, crude endocrine remission rate, and any new hypopituitarism rate were 92.0% (95% CI 87.0%-95.0%), 48.0% (95% CI 35.0%-61.0%), and 21.0% (95% CI 13.0%-31.0%), respectively. For prolactinomas, random effects estimates for crude tumor control rate, crude endocrine remission rate, and any new hypopituitarism rate were 93.0% (95% CI 90.0%-95.0%), 28.0% (95% CI 19.0%-39.0%), and 12.0% (95% CI 6.0%-24.0%), respectively. Meta-regression analysis did not show a statistically significant association between mean margin dose with crude endocrine remission rate or mean margin dose with development of any new hypopituitarism rate for any of the secretory subtypes.

CONCLUSIONS

SRS offers effective tumor control of hormone-producing pituitary adenomas in the majority of patients but a lower rate of endocrine improvement or remission.

Robotic Radiosurgery for Persistent Postoperative Acromegaly in Patients with Cavernous Sinus-Invading Pituitary Adenomas-A Multicenter Experience

Simple Summary

Growth hormone-secreting tumors of the pituitary gland which infiltrate surrounding tissue structures may not be fully resectable. This causes many patients to suffer from acromegaly after an unsuccessful surgery. To limit the considerable morbidity and mortality of such patients, effective and safe treatment options are needed. Fractionated radiotherapy and growth hormone-lowering medication are possible treatment options. Robotic radiosurgery (RRS) may be a suitable treatment modality as well. However, only sparse and heterogeneous data are available. This first retrospective multicenter study investigated the efficacy and safety of RRS for this patient group. Outcomes provide evidence that RRS may achieve biochemical disease control or remission in most of the patients. The hormone levels are decreasing after treatment, whereas favorable risk and safety profiles of RRS were shown. No new tumor growth was observed throughout the available follow-up. These findings may guide future care for this challenging patient population.

Abstract

Background: The rates of incomplete surgical resection for pituitary macroadenomas with cavernous sinus invasion are high. In growth hormone-producing adenomas, there is a considerable risk for persistent acromegaly. Thus, effective treatment options are needed to limit patient morbidity and mortality. This multicenter study assesses the efficacy and safety of robotic radiosurgery (RRS) for patients with cavernous sinus-invading adenomas with persistent acromegaly. Methods: Patients who underwent RRS with CyberKnife for postoperative acromegaly were eligible. Results: Fifty patients were included. At a median follow-up of 57 months, the local control was 100%. The pretreatment insulin-like growth factor 1 (IGF-1) levels and indexes were 381 ng/mL and 1.49, respectively. The median dose and prescription isodose were 18 Gy and 70%, respectively. Six months after RRS, and at the last follow-up, the IGF-1 levels and indexes were 277 ng/mL and 1.14, as well as 196 ng/mL and 0.83, respectively (p = 0.0001 and p = 0.0002). The IGF-1 index was a predictor for biochemical remission (p = 0.04). Nine patients achieved biochemical remission and 24 patients showed biochemical disease control. Three patients developed a new hypopituitarism. Conclusions: RRS is an effective treatment for this challenging patient population. IGF-1 levels are decreasing after treatment and most patients experience biochemical disease control or remission.

Multidisciplinary management of acromegaly: A consensus

The 13th Acromegaly Consensus Conference was held in November 2019 in Fort Lauderdale, Florida, and comprised acromegaly experts including endocrinologists and neurosurgeons who considered optimal approaches for multidisciplinary acromegaly management. Focused discussions reviewed techniques, results, and side effects of surgery, radiotherapy, and medical therapy, and how advances in technology and novel techniques have changed the way these modalities are used alone or in combination. Effects of treatment on patient outcomes were considered, along with strategies for optimizing and personalizing therapeutic approaches. Expert consensus recommendations emphasize how best to implement available treatment options as part of a multidisciplinary approach at Pituitary Tumor Centers of Excellence.