Published online Dec 28, 2016. doi: 10.4329/wjr.v8.i12.916
Peer-review started: June 3, 2016
First decision: July 5, 2016
Revised: September 29, 2016
Accepted: October 17, 2016
Article in press: October 18, 2016
Published online: December 28, 2016
Processing time: 202 Days and 19.3 Hours
To evaluate brain metastases volume control capabilities of stereotactic radiosurgery (SRS) through serial magnetic resonance (MR) imaging follow-up.
MR examinations of 54 brain metastases in 31 patients before and after SRS were reviewed. Patients were included in this study if they had a pre-treatment MR examination and serial follow-up MR examinations at 6 wk, 9 wk, 12 wk, and 12 mo after SRS. The metastasis volume change was categorized at each follow-up as increased (> 20% of the initial volume), stable (± 20% of the initial volume) or decreased (< 20% of the initial volume).
A local tumor control with a significant (P < 0.05) volume decrease was observed in 25 metastases at 6-wk follow-up. Not significant volume change was observed in 23 metastases and a significant volume increase was observed in 6 metastases. At 9-wk follow-up, 15 out of 25 metastases that decreased in size at 6 wk had a transient tumor volume increase, followed by tumor regression at 12 wk. At 12-wk follow-up there was a significant reduction in volume in 45 metastases, and a significant volume increase in 4 metastases. At 12-mo follow-up, 19 metastases increased significantly in size (up to 41% of the initial volume). Volume tumor reduction was correlated to histopathologic subtype.
SRS provided an effective local brain metastases volume control that was demonstrated at follow-up MR imaging.
Core tip: Stereotactic radiosurgery (SRS) provided an effective long-term local volume control of brain metastases during 12-mo magnetic resonance (MR) imaging follow-up. A significant reduction of the tumor volume by 6 wk post-SRS was associated with long-term volume control suggesting that the timing for MR imaging follow-up at 6 wk, 9 wk, 12 wk and 12 mo after SRS, could be considered the most effective to provide useful information to make the best treatment decisions.