Safety and Efficacy of Primary Multisession Dose Fractionated Gamma Knife Radiosurgery for Jugular Paragangliomas

The Radiosurgery Society Case-Based Discussion of the Management of Head and Neck or Skull Base Paragangliomas with Stereotactic Radiosurgery and Radiotherapy

Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) have been used for the treatment of head and neck or skull base paraganglioma for a considerable time, demonstrating promising local control rates and a favorable safety profile compared with surgical approaches. Nevertheless, the choice of treatment must be carefully tailored to each patient's preferences, tumor location, and size, as well as anticipated treatment-related morbidity. This case-based review serves as a practical and concise guide for the use of SRS and FSRT in the management of head and neck or skull base paragangliomas, providing information on the diagnosis, treatment, follow-up considerations, and potential pitfalls.

Safety and Efficacy of Primary Hypofractionated Gamma Knife Radiosurgery for Giant Hypothalamic Hamartoma

OBJECTIVE

To describe the feasibility, safety, efficacy, and complication profile of primary hypofractionated gamma knife radiosurgery (GKRS), and practical nuances of performing the same in pediatric patients.

METHODS

Three pediatric patients (age range 17-65 mo) underwent primary hypofractionated GKRS in 2-3 consecutive days with interfraction interval of 24 h. All patients had precocious puberty and were on GnRH analogue. Frame based GKRS done with 8.1-9.2 Gy radiation per fraction at 50% isodose in 2-3 fractions targeting the entire hamartoma volume. The mean target volume was 5.67 cc (4.45-7.39 cc). The authors followed these patients for clinical and endocrinological assessment at every 6 mo interval while the repeat MRI done at 6 mo and then annually. The seizure outcome analysis was done using Engel scale.

RESULTS

At a mean follow up of 27 mo (24-30 mo), 2 patients became Engel class 3 while one achieved Engel class 1 control. 2 patients showed halted pubertal growth with no additional hormonal aberration. 2 patients showed significant volumetric reduction (48% and 32%) and patchy necrosis inside the hypothalamic hamartoma (HH). There was no deficit in visual function, memory and cognition. One patient showed reduction in aggressiveness.

CONCLUSION

Giant HH are exceptionally difficult neurological diseases. Primary hypofractionated GKRS may be an alternative approach as mono/multitherapy with promising results and minimal complication.

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.

Primary Hypofractionated Gamma Knife Radiosurgery for Giant Cavernous Sinus Hemangiomas

Cavernous sinus hemangioma (CSH) are notoriously difficult to excise because of their location, propensity for profuse bleeding during surgery, and relationship to complex neurovascular structures. Radiosurgery offers an alternative treatment modality in cases of small and medium-sized CSH. However, no reports are available in the world literature detailing gamma knife radiosurgery (GKRS) in large (3-4 cm) and giant (>4 cm) CSH. Two patients with giant CSH (Tumor volume was 72.2 and 99.8 cm³, respectively) were treated with frame-based fractionated GKRS (5 Gy × 5 #). The treatment was done with Leksell Perfexion with frame in situ and interfraction interval of 24 h. The tumor was engulfing the optic apparatus, and chiasma could not be separated delineated. The patients were followed at 3 months interval with clinic-radiologic evaluation. Following GKRS, both patients showed remarkable clinical improvement in presenting complaints of headache and visual deterioration. Sixth nerve paresis recovered completely in case no. 1. Significant reduction in tumor volumes (85.1 and 75.6% respectively) was noticed in both the patients at 6 months follow-up radiology. Transient alopecia was noted in case 1 at 3 months follow-up that completely resolved by the 6 months. There was no complication till the last follow-up of 9 months. We report the first account of five fraction frame-based hypo fractionated GKRS for giant CSH. At an interval as short as 3 months, giant CSH shows remarkable clinical improvement. Primary hypofractionated GKRS may be considered an alternative effective modality in these difficult lesions with a favorable safety profile.

Image-guided robotic radiosurgery for glomus jugulare tumors-Multicenter experience and review of the literature

BACKGROUND

Glomus jugulare tumors (GJTs) are challenging to treat due to their vascularization and location. This analysis evaluates the effectiveness and safety of image-guided robotic radiosurgery (RRS) for GJTs in a multicenter study and reviews the existing radiosurgical literature.

METHODS

We analyzed outcome data from 101 patients to evaluate local control (LC), changes in pretreatment deficits, and toxicity. Moreover, radiosurgical studies for GJTs have been reviewed.

RESULTS

After a median follow-up of 35 months, the overall LC was 99%. Eighty-eight patients were treated with a single dose, 13 received up to 5 fractions. The median tumor volume was 5.6 cc; the median treatment dose for single-session treatments is 16 Gy, and for multisession treatments is 21 Gy. Fifty-six percentage of patients experienced symptom improvement or recovered entirely.

CONCLUSIONS

RRS is an effective primary and secondary treatment option for GJTs. The available literature suggests that radiosurgery is a treatment option for most GJTs.

Stereotactic Radiosurgery and Stereotactic Radiotherapy for Malignant Skull Base Tumors

The role of stereotactic radiosurgery/stereotactic radiotherapy (SRS/SRT) for malignant skull base tumors was summarized and discussed. The treatment of skull base tumors remains challenging. Their total resection is often difficult. SRS/SRT is one useful treatment option for residual or recurrent tumors after surgical resection in cases of primary skull base tumors. If skull base metastasis and skull base invasion are relatively localized, they can be candidates for SRS/SRT. Low rates of cervical lymph node involvement in early-stage (N0M0, no lymph node involvement or distant metastasis) nasal and paranasal carcinomas (NpNCa) and external auditory canal carcinomas (EACCa) have been reported in the literature. Such cases might be good candidates for SRS/SRT as the initial therapy. We previously reported the results of SRS/SRT for various malignant extra-axial skull base tumors. In addition, treatment results of early-stage head and neck carcinomas were summarized. Those of our data and those of other reported series were reviewed here to clarify the usefulness of SRS/SRT for malignant extra-axial skull base tumors.