Role of radiosurgery in the management of glomus tumors

Feasibility Study of Stereotactic Radiosurgery Treatment of Glomus Jugulare Tumors via HyperArc VMAT

This study aims to report on the clinical validation and feasibility of utilizing a novel fully automated treatment planning and delivery system, HyperArc VMAT stereotactic radiosurgery (SRS) for glomus jugulare tumors (GJT). Independent dose verification of the HyperArc module via the MD Anderson's SRS head phantom irradiation and credentialing results showed compliance with the SRS treatment requirements per IROC MD Anderson's standard. Following the Alliance clinical trial, AAPM, RTOG protocols, and QUENTAC requirements, utilizing selected three-partial arc geometry of HyperArc module on TrueBeam Linac with 6MV-FFF beam, GJT SRS plans were generated for nine previously treated Gamma Knife (GK) radiosurgery patients using advanced Acuros-based algorithm to account for tissue inhomogeneity corrections and frameless immobilization with Q-fix mask and Encompass device insert. HyperArc VMAT produced highly conformal SRS dose distributions to GJT, a steep dose gradient around the GJT, and spared adjacent critical organs including the spinal cord (< 3.0 Gy). Due to faster patient setup and less MLC modulation through the target (average beam-on time, 6.2 minutes), the HyperArc VMAT plan can deliver a single high-dose of 18 Gy to the GJT in less than 15 minutes overall treatment time, significantly improving patient comfort and clinic workflow. Pretreatment portal dosimetry quality assurance results and independent dose verification via Monte Carlo-based physics second check met our clinical SRS protocol's requirements for treatment. Due to the highly conformal dose distribution, rapid dose fall-off, excellent sparing of adjacent critical organs, and highly precise and accurate treatment, clinical implementation of frameless HyperArc VMAT for GJT patients who may not have access to nor tolerate frame-based GK SRS treatment are underway.

The Long-Term Outcome of CyberKnife-Based Stereotactic Radiotherapy for Head and Neck Paragangliomas: A Single-Center Experience

OBJECTIVE

To assess long-term outcomes of hypofractionated stereotactic radiotherapy (hSRT) for head and neck paragangliomas (HNPGs).

METHODS

Patients who underwent hSRT with CyberKnife for HNPGs from 2010 to 2019 were retrospectively reviewed.

RESULTS

A total of 34 HNPGs in 29 patients were identified. Mean patient age was 50 ± 16 years, and 15 patients (52%) were female. Fifteen patients (55%) had undergone previous procedures. Four cases (14%) were functional in hormone production. According to the Fisch classification, 1 (3%) case was B, 12 (42%) cases were C, 14 (48%) cases were D, and 2 (7%) cases were unclassified.¹ The median prescribed dose covering 95% of the planning target volume was 2500 cGy (interquartile range 2100-2600 cGy), and the median target volume was 10 cm³ (interquartile range 6.0-18.3 cm³). The local control rate was 97%. The median progression-free survival was 66 months (interquartile range 28-95 months), and 96% of patients were free of tumor progression at 8 years. During follow-up, 1 case (3%) resulted in permanent facial nerve palsy (House-Brackmann grade II), and another case (3%) resulted in asymptomatic cerebellar radiation necrosis. Univariate and multivariate analysis showed that no previous surgical history (odds ratio 8.58, 95% confidence interval 1.2-59.7, P = 0.03) was a positive predictor of symptomatic improvement.

CONCLUSIONS

hSRT for HNPGs was an effective treatment with minimal side effects over the long term and may have a role as first-line therapy, especially for symptomatic nonfunctional HNPGs, for better symptom control.

Treatment of patients with glomus jugulare tumours (GJT) and its subjective effect on quality of life (QoL) measures

Cerebellopontine angle (CPA) tumours account for 6-10% of intracranial tumours. The most common CPA tumours are vestibular schwannomas (VS), also known as acoustic neuromas, benign tumours of the vestibulocochlear nerve. Less common but symptomatic skull base lesions are glomus jugulare tumours (GJT), of which approximately 40% are identified as CPA tumours. Initial symptoms for GJT may include hearing loss and tinnitus and progress to various cranial nerve dysfunctions. Three well-accepted treatment modalities for such tumours include surgical resection, radiotherapy and/or conservative management employing serial MR or CT imaging. Patients' quality of life may be impacted by different treatment methods, so treatment decisions should be client centered.

Long term outcomes with linear accelerator stereotactic radiosurgery for treatment of jugulotympanic paragangliomas

BACKGROUND

Data supporting linear accelerator (linac) stereotactic radiosurgery (SRS) for jugulotympanic paragangliomas (JTPs) come from small series with minimal follow-up. Herein, we report a large series of JTPs with extended follow-up after frameless linac-based SRS.

METHODS

JTPs treated with linac-based SRS from 2002 to 2019 with 1+ follow-up image were reviewed for treatment failure (radiographic or clinical progression, or persistent symptoms after SRS requiring intervention) and late toxicities (CTCAE v5.0).

RESULTS

Forty JTPs were identified; 30 were treated with a multifraction regimen. Median clinical and radiographic follow-up was 79.7 (interquartile range [IQR] 31.7-156.9) and 54.4 months (IQR 17.9-105.1), respectively, with a median 4.5 follow-up scans (IQR 2-9). Seven-year progression-free survival (PFS) was 97.0% (95% confidence interval 91.1%-100.0%). PFS was similar between single- and multifraction regimens (log rank P = .99). Toxicity was seen in 7.7% (no grade III).

CONCLUSIONS

With extended clinical and radiographic follow-up, frameless linac-based SRS provides excellent local control with mild toxicity <8%.

Stereotactic radiosurgery for head and neck paragangliomas: a systematic review and meta-analysis

Head and neck paragangliomas (HNPs) are rare, usually benign hyper vascularized neuroendocrine tumors that traditionally have been treated by surgery, with or without endovascular embolization, or, more recently stereotactic radiosurgery (SRS). The aim of our study is to determine the clinical and radiographic effectiveness of SRS for treatment of HNPs. A systematic search of electronic databases was performed, and 37 articles reporting 11,174 patients (1144 tumors) with glomus jugulare (GJT: 993, 86.9%), glomus tympanicum (GTT: 94, 8.2%), carotid body tumors (CBTs: 28, 2.4%), and glomus vagale (GVT: 16, 1.4%) treated with SRS definitively or adjuvantly were included. The local control (LC) was estimated from the pooled analysis of the series, and its association with SRS technique as well as demographic and clinical factors was analyzed. The median age was 56 years (44-69 years). With a median clinical and radiological follow-up of 44 months (9-161 months), LC was 94.2%. Majority of the patients (61.0%) underwent Gamma Knife Radiosurgery (GKS), but there was no statistically significant difference in LC depending upon the SRS technique (p = 0.9). Spearmen's correlation showed that LC was strongly and negatively correlated with multiple parameters, which included female gender (r = - 0.4, p = 0.001), right-sided tumor (r = - 0.3, p = 0.03), primary SRS (r = - 0.5, p ≤ 0.001), and initial clinical presentation of hearing loss (r = - 0.4, p = 0.001). To achieve a LC ≥ 90%, a median marginal dose (Gy) of 15 (range, 12-30 Gy) was required. The results corroborate that SRS in HNPs is associated with good clinical and radiological outcome.

LINAC radiosurgery for glomus jugulare tumors: retrospective - cohort study of 23 patients

BACKGROUND

Glomus jugulare tumors (GJTs) are uncommon and locally disruptive tumors that usually arise within the jugular foramen of the temporal bone. Surgery was the treatment of choice up until recently. In the last decades, however, radiosurgery has surfaced as a promising alternative treatment by providing excellent tumor control with low risk of cranial nerve injuries. Our aim was to examine the results of radiosurgery specifically, linear accelerator stereotactic radiosurgery (LINAC SRS) for GJT treatment. We hypothesized that radiosurgery will reduce the size of the tumor and improve neurological symptoms.

DESIGN AND METHOD

Between January 1, 1994 and December 31, 2013, 30 patients with GJTs were treated in Sheba Medical Center using LINAC SRS treatment. Comprehensive clinical follow-up was available for 23 patients. Sixteen patients were female and seven males with a median age of 64 years, with a range of 18-87 years. In 19 of the patients, LINAC SRS was the primary treatment, whereas in the remaining four cases, surgery or embolization preceded radiosurgery. The median treated dose to tumor margin was 14 Gy (range 12-27 Gy), and the median tumor volume before treatment was 5 ml (range 0.5-15 ml).

RESULTS

Following the LINAC SRS treatment, 14 of 23 patients (60%) showed improvement of previous neurological deficits, nine patients (40%) remained unchanged. At the end of a follow-up, tumor reduction was seen in 13 patients and a stable volume in eight (91% tumor control rate). Two cases of tumor progression were noted. Three patients (13%) had post- SRS complications during the follow-up, two of which achieved tumor control, while in one the tumor advanced.

CONCLUSIONS

LINAC SRS is a practical treatment option for GJTs, with a high rate of tumor control and satisfactory neurological improvement.

Protontherapy of head and neck paragangliomas: A monocentric study

PURPOSE

The aim of this study was to assess efficacy and safety of proton beam therapy of paragangliomas of the head and neck, rare benign tumours developed close to crucial structures such as cranial nerves and vascular tissues.

PATIENTS AND METHODS

Ten patients with a paraganglioma of the head and neck were treated from 2001 to 2014 with image-guided proton therapy. Neurological and ear nose throat symptoms were collected in addition to audiometric testing, before and after the treatment. Acute and late toxicities were assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.

RESULTS

Median age at diagnosis was 52.6years (range: 18.2-65.8years). Proton therapy was the exclusive treatment in six patients and four patients had a postoperative radiotherapy. Median dose was 50.4Gy relative biological effectiveness (RBE; range: 45.0-67.0Gy). With a median follow-up of 24.6months (range: 6.7-46.2 months), local tumour control rate was 100% (stable, n=10). No upper grade 2 acute toxicity was reported. To the latest news, seven patients had controlled symptoms (improved, n=1, stabilized, n=6). One patient out of seven with initial tinnitus had a decrease in his symptoms, while the six other patients had a sustained stabilization.

CONCLUSION

Proton beam therapy is an effective and well-tolerated treatment modality of skull base paragangliomas, with documented functional benefit. A longer follow-up is planned in order to assess local control and long-term toxicities.

Stereotactic Radiosurgical Treatment of Glomus Jugulare Tumors

OBJECTIVE

Determine treatment outcomes of stereotactic radiosurgery (SRS) for glomus jugulare tumors (GJT), focusing on three-dimensional volume change and symptoms before and after SRS, as well as complications related to SRS.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Thirty-eight patients treated with SRS between 2000 and 2015.

INTERVENTION

SRS treatment of GJT.

MAIN OUTCOME MEASURES

The tumor volumes on pre- and posttreatment imaging were compared utilizing the Leskell GammaPlan treatment plan software to assess tumor progression. Pre- and posttreatment symptoms, Fisch classification, and complications were recorded.

RESULTS

The mean radiographic follow-up was 39.1 months. The mean dose-to-tumor margin was 13.2 Gy. The mean tumor size at treatment was 5.8 and 5.2 cm at last follow-up. Thirty-three patients had follow-up imaging suitable for analysis. When defining both 10 and 15% tumor size increases as significant, 27 (82%) and 29 (88%) tumors decreased in size or remained stable, respectively. For the seven tumors with documented pre-SRS growth, treatment success was 86%. The mean marginal dose for treatment success and failure were 13.2 and 13.7 Gy, respectively. Patients receiving a higher margin dose had a greater risk of tumor progression (p = 0.0277). Fisch classification did not impact tumor progression rate. Initial tumor volume had no significance on tumor response to SRS.

CONCLUSIONS

SRS is an effective treatment option for GJT. Both initial tumor volume and Fisch classification did not impact tumor progression. There were no significant patient or lesion characteristics that distinguished treatment success and/or failure.