Radiosurgery and stereotactic radiotherapy with cyberknife system for meningioma treatment

Abstract

Objective The aim of this work was to evaluate the impact of stereotactic radiosurgery/fractionated stereotactic radiotherapy with the Cyberknife system on local disease control, clinical outcome and toxicity in patients with meningioma, according to the site and histological grade of lesion. From January 2013 to April 2017, 52 patients with intracranial meningiomas were treated with the Cyberknife system. Twenty-four patients had undergone previous surgery: 38% gross total resection, 10% subtotal resection; 27 patients underwent no surgery; 22 patients had a recurrence of meningioma. Methods Radiosurgery was used for lesions smaller than 2 cm, stereotactic radiotherapy for lesions larger than 2 cm, or smaller but close to a critical site such as the optical chiasm, optic pathway or brainstem. Results Local control and clinical outcomes were analysed. Median follow-up was 20 months: six patients died, one after re-surgery died from post-surgical sepsis, three from heart disease. Progression-free survival had a mean value of 38.3 months and overall survival of 41.6 months. We evaluated at 12 months 28 patients (100% local control); at 24 months 19 patients (89% local control); at 36 months nine patients (89% local control). At baseline, 44/52 patients (85%) were symptomatic: 19 visual disorders, 17 motor disorders, six hearing disorders, 10 headache and six epilepsy. Visual symptoms remained unchanged in 52%, improved in 32%, resolved in 16%. Headache was improved in 40%, resolved in 10%, unchanged in 50%. Epilepsy was resolved in 17%, unchanged in 33%, worsened in 33%. Conclusions Stereotactic radiosurgery/fractionated stereotactic radiotherapy with Cyberknife provides a good local disease control, improving visual, hearing and motor symptoms.

Indications, feasibility, safety, and efficacy of CyberKnife radiotherapy for the treatment of olfactory groove meningiomas: a single institutional retrospective series

“…The CyberKnife system allows for the delivery of 6 MV photons for radiotherapy via an image-guided radiosurgical treatment platform with a frameless robotic manipulator and 6D Skull Tracking system to highly conformal intracranial high-dose tumor targeting, with sub-millimeter precision beam delivery and steep dose gradients achievable around the contoured target volume [11,12,15]. These advantages have allowed CKRT to be a feasible option for patients who are not considered suitable for surgery or cannot tolerate frame-based RT.…”

“…SRT (HRST and FSRT) delivered at lower doses over several fractions can be used for tumors that are within close proximity to critical neurovasculature structures to achieve tissue sparing of radiation-associated adverse events [7,8]. In addition, SRT can be used to treat large OGMs (> 10 cm 3 ) that may be in close proximity to the optic apparatus [8,11,18,21]. In our case series, 4 patients with smaller sized OGMs within close proximity to the optic chiasm and 4 patients with larger OGMs with a median tumor volume of 10.1 cm 3 were treated with SRT.…”

“…In our case series, 4 patients with smaller sized OGMs within close proximity to the optic chiasm and 4 patients with larger OGMs with a median tumor volume of 10.1 cm 3 were treated with SRT. In general, HSRT delivered over 2 to 5 fractions is significantly more convenient than the 25-28 fractions delivered over 4 to 6 weeks required for FRST, however FSRT has been found to have a radiobiological advantage in sparing late-responding tissues [7,11,18]. The median treated tumor volume (8.12 cm 3 ) in our cohort was similar compared to that in the series reported by Gande et al using GK (median 8.5 cm 3 ) [5] but was significantly larger compared to the cohort reported by Zaorsky and colleagues using LINAC (2.97 cm 3 ) [6].…”

“…Among the RT technologies available, CKRT is a more recent image-guided frameless robotic system, which is designed for SRS and stereotactic radiation therapy (SRT) [11,12]. The associated 6D skull tracking system enables highly conformal intracranial high-dose tumor targeting, with sub-millimeter precision in beam delivery allowing for steep dose gradients achievable around the contoured tumor.…”

Hearing preservation after Gamma Knife radiosurgery for cerebellopontine angle meningiomas

“…Moreover, auditory function is also not commonly reported on in radiotherapy series, with more focus on tumor control and adverse radiation effects. Di Franco et al 13 reported on the use of the Cyberknife for the treatment of meningiomas with a mix of SRS and fractionated stereotactic radiotherapy (FSRT) cases. A single fraction was used to treat lesions less than 2 cm, while FSRT was used to treat lesions greater than 2 cm or less than 3 cm, but too close to a critical site, such as the optical chiasm or CPA.…”