Transcript
Hello, thank you for having me here today. So I'm just going to be going over our experience at Kaiser with the new Brainlab's Elements System. So I'm from the residency program at Radiation Oncology in Kaiser Permanente. We're in Los Angeles. We started using the Brainlab Elements System at our institution starting last summer, and we treat up to 15 brain metastases per session with this system. And we're looking at the safety and the efficacy of our results.
So we started treating in May of last year, and I looked at the first 40 patients that we treated, the last one was in December of 2017, so that we could have some follow-up results. Currently, we have about 80 to 90 patients treated, over 500 lesions. So the treatment plans were made using five to six couch positions with up to 12 dynamic conformal arcs using 6X or 6XFFF modes. And it was developed with the TrueBeam System with the ExacTrac, and our corrections were 0.5 millimeters and 0.5 degrees as in the talk earlier. The dose was prescribed as per the treatment lesion volume, as our institutional standard was.
So in our first 40 patients, we treated 283 lesions, 40 unique patients, 7 retreatments, so 47 treatment sessions in all. Median treatment time was relatively short at 25 minutes. Twenty-one patients received immunotherapy around the time of the SRS session, and I listed out the pathology as well as some of the patient characteristics. We treated a wide range of volumes, generally pretty small, but there were some, especially some post-op cases, that raised the total volume that we treated. And we also looked at the whole brain dose and the hippocampal doses from our plans, and they were relatively low, about 120 to 130 centigrays on average.
So this is just what we use for the dose per volume, and this is just our institutional standard. Most patients were treated in a single session. For the larger volumes, we do sometimes fractionate them out to three sessions, and I just listed them in here. And then here are our results. So at the medium imaging follow-up time of 2.2 months, it's much longer now, but this is just when I did the analysis. There were six patients who showed radiographic enlargement of the treated lesions. And this is just any of the treated lesions. So if you had ten lesions, if one of them enlarged, then it counted as a failure. But if the other nine were treated... So actually, our control's probably actually better than that. At the time of our analysis, 70% of the patients were still alive, and 50% of the deaths were likely due to neurological causes. That was only significantly associated with a number of lesions that was treated.
At the time of the analysis, there were no cases of radiation necrosis. Right now, I've been keeping track of all of the patients in our database, and there have been two patients at this time who have developed radiation necrosis. There were three patients who developed seizures, but all of these were happening more than ten days after the radiosurgery date, so it most likely was not related to the actual radiosurgery procedure itself. And I have also listed some of our grade 2 and 3 side effects, and most of them improved with steroids. On analysis, our toxicity was significantly associated with the total treated volume, but not with the number of treated lesions. And the toxicities were greater for patients who had a total lesion treated volume of over 5 ccs, and that was significant.
So conclusion, this is a safe, quick, effective method for treating patients with multiple brain metastases. Total lower monitoring units allowed for a total lower integral whole brain and hippocampal dose, and there was an acceptable level of lesion control and toxicities. And of these toxicities, possibly not all of them were related to the actual radiosurgery procedure. So I just wanted to do some images to show two of the cases.
So this is a lady, 40 years old, with renal cell carcinoma. We treat 30 lesions over 4 different sessions because she kept on developing new metastases. And the range of the lesion volumes was from 0.02 cc to 1.00 cc. So on the left side here, this is the image from the time of the radiosurgery planning. And this right side is actually from one of the retreatments. So you can see these three lesions here have responded. We overlaid the contours on our repeat planning treatment. These have responded. And then this was a new lesion that we treated at a subsequent session. So she had a pretty good response.
And then this is a second case. This is a 62-year-old woman with lung adenocarcinoma, much smaller lesions, 0.01 cc to 0.23 ccs. And, I don't know where the image is. So the left sides are the pretreatment MRI. And this is the after treatment. And you can see these are very small lesions, but I did alter these so that you can see that the lesions did disappear on the follow up MRI, about four and a half months after. And she had 14 lesions originally, and 12 of them had a complete response. So it shows that even for very small lesions, this is a effective treatment. I got one more.
Okay. All right, and I'd just like to acknowledge my department and to all of you all for having me here today. Thank you.
So we started treating in May of last year, and I looked at the first 40 patients that we treated, the last one was in December of 2017, so that we could have some follow-up results. Currently, we have about 80 to 90 patients treated, over 500 lesions. So the treatment plans were made using five to six couch positions with up to 12 dynamic conformal arcs using 6X or 6XFFF modes. And it was developed with the TrueBeam System with the ExacTrac, and our corrections were 0.5 millimeters and 0.5 degrees as in the talk earlier. The dose was prescribed as per the treatment lesion volume, as our institutional standard was.
So in our first 40 patients, we treated 283 lesions, 40 unique patients, 7 retreatments, so 47 treatment sessions in all. Median treatment time was relatively short at 25 minutes. Twenty-one patients received immunotherapy around the time of the SRS session, and I listed out the pathology as well as some of the patient characteristics. We treated a wide range of volumes, generally pretty small, but there were some, especially some post-op cases, that raised the total volume that we treated. And we also looked at the whole brain dose and the hippocampal doses from our plans, and they were relatively low, about 120 to 130 centigrays on average.
So this is just what we use for the dose per volume, and this is just our institutional standard. Most patients were treated in a single session. For the larger volumes, we do sometimes fractionate them out to three sessions, and I just listed them in here. And then here are our results. So at the medium imaging follow-up time of 2.2 months, it's much longer now, but this is just when I did the analysis. There were six patients who showed radiographic enlargement of the treated lesions. And this is just any of the treated lesions. So if you had ten lesions, if one of them enlarged, then it counted as a failure. But if the other nine were treated... So actually, our control's probably actually better than that. At the time of our analysis, 70% of the patients were still alive, and 50% of the deaths were likely due to neurological causes. That was only significantly associated with a number of lesions that was treated.
At the time of the analysis, there were no cases of radiation necrosis. Right now, I've been keeping track of all of the patients in our database, and there have been two patients at this time who have developed radiation necrosis. There were three patients who developed seizures, but all of these were happening more than ten days after the radiosurgery date, so it most likely was not related to the actual radiosurgery procedure itself. And I have also listed some of our grade 2 and 3 side effects, and most of them improved with steroids. On analysis, our toxicity was significantly associated with the total treated volume, but not with the number of treated lesions. And the toxicities were greater for patients who had a total lesion treated volume of over 5 ccs, and that was significant.
So conclusion, this is a safe, quick, effective method for treating patients with multiple brain metastases. Total lower monitoring units allowed for a total lower integral whole brain and hippocampal dose, and there was an acceptable level of lesion control and toxicities. And of these toxicities, possibly not all of them were related to the actual radiosurgery procedure. So I just wanted to do some images to show two of the cases.
So this is a lady, 40 years old, with renal cell carcinoma. We treat 30 lesions over 4 different sessions because she kept on developing new metastases. And the range of the lesion volumes was from 0.02 cc to 1.00 cc. So on the left side here, this is the image from the time of the radiosurgery planning. And this right side is actually from one of the retreatments. So you can see these three lesions here have responded. We overlaid the contours on our repeat planning treatment. These have responded. And then this was a new lesion that we treated at a subsequent session. So she had a pretty good response.
And then this is a second case. This is a 62-year-old woman with lung adenocarcinoma, much smaller lesions, 0.01 cc to 0.23 ccs. And, I don't know where the image is. So the left sides are the pretreatment MRI. And this is the after treatment. And you can see these are very small lesions, but I did alter these so that you can see that the lesions did disappear on the follow up MRI, about four and a half months after. And she had 14 lesions originally, and 12 of them had a complete response. So it shows that even for very small lesions, this is a effective treatment. I got one more.
Okay. All right, and I'd just like to acknowledge my department and to all of you all for having me here today. Thank you.