Linac-based stereotactic radiosurgery and fractionated stereotactic radiotherapy with a micro-multileaf collimator for brain metastasis in the primary motor cortex.

Abstract

This study aimed to assess the clinical outcomes of linear accelerators (linac)-based, stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (fSRT) with a micro-multileaf collimator for brain metastasis in the primary motor cortex (BMPMC). Thirty-five consecutive patients with BMPMC who were treated by linac-based SRS or fSRT between January 2012 and March 2020 were analyzed. BMPMC was defined as a tumor located in the precentral gyrus on gadolinium-enhanced magnetic resonance imaging (MRI) and T2-weghted imaging (T2WI). In total, 35 patients with 37 metastases were analyzed. The median follow-up time was 13 (range: 1-97) months. The tumor volume was 0.05-26.5 (median: 0.62) cm3. All patients were treated with SRS or fSRT using 35 Gy with 7 Gy per fraction daily. The median survival time (MST) was 16.9 months. The pretreatment KPS and RPA class significantly differed in terms of MST on the log-rank tests. Seven symptomatic patients had hemiparesis before SRS or fSRT. All symptomatic patients, except one with facial paresis and one who died within 3 months, experienced improvement at a 3 month follow-up. None of the patients presented with persistent radiation injury at the final follow-up. Two patients presented with grade 3 radiation-related central nervous system necrosis, which was assessed using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. In BMPMC, SRS and fSRT had good tumor control and did not cause serious complications. Therefore, they are suitable treatment options with an acceptable safety profile.

• Authors: Ryosuke Matsuda, Masatoshi Hasegawa, Tetsuro Tamamoto, Tomoko Ochi, Toshiteru Miyasaka, Nobuyoshi Inooka, Shigeto Hontsu, Sachiko Miura, Yasuhiro Takeshima, Kentaro Tamura, Shuichi Yamada, Fumihiko Nishimura, Ichiro Nakagawa, Yasushi Motoyama, Young-Soo Park, Hiroyuki Nakase
• Journal: Journal of radiation research (J Radiat Res) Vol. 63 Issue 1 Pg. 63-70 (Jan 20 2022) ISSN: 1349-9157 [Electronic] England
• PMID: 34927204 (Publication Type: Journal Article)
• Copyright: © The Author(s) 2021. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology.

Topics

• Brain (pathology)
• Brain Neoplasms (secondary)
• Humans
• Magnetic Resonance Imaging
• Motor Cortex (pathology)
• Radiosurgery (methods)