scholarly journals Clinical dose profile of Gamma Knife stereotactic radiosurgery for extensive brain metastases

2020 ◽  
pp. 1-5
Author(s):  
Gregory Neil Bowden ◽  
Jong Oh Kim ◽  
Andrew Faramand ◽  
Kevin Fallon ◽  
John Flickinger ◽  
...  

OBJECTIVEThe use of Gamma Knife stereotactic radiosurgery (GKSRS) for the treatment of extensive intracranial metastases has been expanding due to its superior dosimetry and efficacy. However, there remains a dearth of data regarding the dose parameters in actual clinical scenarios. The authors endeavored to calculate the radiation dose to the brain when treating ≥ 15 brain metastases with GKSRS.METHODSThis retrospective analysis reviewed dosage characteristics for patients requiring single-session GKSRS for the treatment of ≥ 15 brain metastases. Forty-two patients met the inclusion criteria between 2008 and 2017. The median number of tumors at the initial GKSRS procedure was 20 (range 15–39 tumors), accounting for 865 tumors in this study. The median aggregate tumor volume was 3.1 cm3 (range 0.13–13.26 cm3), and the median marginal dose was 16 Gy (range 14–19 Gy).RESULTSThe median of the mean brain dose was 2.58 Gy (range 0.95–3.67 Gy), and 79% of patients had a dose < 3 Gy. The 12-Gy dose volume was a median of 12.45 cm3, which was equivalent to 0.9% of the brain volume. The median percentages of brain receiving 5 Gy and 3 Gy were 6.7% and 20.4%, respectively. There was no correlation between the number of metastases and the mean dose to the brain (p = 0.8). A greater tumor volume was significantly associated with an increased mean brain dose (p < 0.001). The median of the mean dose to the bilateral hippocampi was 2.3 Gy. Sixteen patients had supplementary GKSRS, resulting in an additional mean dose of 1.4 Gy (range 0.2–3.8 Gy) to the brain.CONCLUSIONSGKSRS is a viable means of managing extensive brain metastases. This procedure provides a relatively low dose of radiation to the brain, especially when compared with traditional whole-brain radiation protocols.

2020 ◽  
Vol 2 (Supplement_2) ◽  
pp. ii2-ii2
Author(s):  
Greg Bowden ◽  
Jong Kim ◽  
Andrew Faramand ◽  
Kevin Fallon ◽  
John Flickinger ◽  
...  

Abstract BACKGROUND The use of Gamma Knife stereotactic radiosurgery (GKSRS) for the treatment of extensive intracranial metastases has been expanding due to its superior dosimetry and efficacy. However, there remains a dearth of data regarding the dose parameters in actual clinical scenarios. We endeavored to calculate the radiation dose to the brain when treating &gt;15 brain metastases with GKSRS. METHODS This retrospective analysis reviewed dosage characteristics for patients requiring single session GKSRS for the treatment of 315 brain metastases. Forty-two patients met the inclusion criteria between 2008 and 2017. The median number of tumors at the initial GKSRS procedure was 20 (15–39) which accounted for 865 tumors in this study. The median aggregate tumor volume was 3.1cm3(0.13–13.26) and the median marginal dose was 16Gy (14-19Gy). RESULTS The median of the mean brain dose was 2.58Gy (range 0.95–3.67Gy) and 79% of patients had a dose &lt;3Gy. The 12Gy dose volume was a median of 12.45cm3, which was equivalent to 0.9% of the brain volume. The median percentage of brain receiving 5Gy and 3Gy was 6.7% and 20.4%, respectively. There was no correlation between the number of metastases and the mean dose to the brain (p=0.8). A higher tumor volume was significantly associated with an increased mean brain dose (p&lt;0.001). The median of the mean dose to the bilateral hippocampi was 2.3Gy. Sixteen patients had supplementary GKSRS, resulting in an additional mean dose of 1.4Gy (0.2–3.8Gy) to the brain. CONCLUSION GKSRS is a viable means of managing extensive brain metastases. This procedure provides a relatively low dose of radiation to the brain, especially when compared to traditional whole brain radiation protocols.


2021 ◽  
Author(s):  
Sean Sachdev ◽  
Timothy L. Sita ◽  
Mahesh Gopalakrishnan ◽  
Michael K. Rooney ◽  
Alexander Ho ◽  
...  

Abstract Purpose:Gamma Knife (GK) stereotactic radiosurgery (SRS) is increasingly used as an initial treatment for patients with ten or more brain metastases (BM). However, the clinical and dosimetric consequences of this practice are not well established.Methods: We performed a single institution, retrospective analysis of 30 patients who received GK SRS for ten or more BM in one session. We utilized MIM Software to contour the whole brain and accumulated the doses from all treated lesions to determine the mean dose delivered to the whole brain. Patient outcomes were determined from chart review. Results: Our cohort had a median number of 13 treated lesions (range 10 to 26 lesions) for a total of 427 treated lesions. The mean dose to the whole brain was determined to be 1.8 ± 0.91 Gy (range 0.70 to 3.8 Gy). Mean dose to the whole brain did not correlate with the number of treated lesions (Pearson r=0.23, p=0.21), but was closely associated with tumor volume (Pearson r=0.95, p<0.0001). There were no significant correlations between overall survival and number of lesions or aggregate tumor volume. Fourteen patients (47%) underwent additional SRS sessions and six patients (20%) underwent WBRT a median of 6.6 months (range 3.0-50 months) after SRS. Two patients (6.6%) developed grade 2 radionecrosis following SRS beyond earlier WBRT.Conclusion: The mean dose to the whole brain in patients treated with GK SRS for 10 or more BM remained low with an acceptable rate of radionecrosis. This strategy allowed the majority of patients to avoid subsequent WBRT.


2019 ◽  
Vol 1 (Supplement_1) ◽  
pp. i27-i27
Author(s):  
Carolina Benjamin ◽  
Monica Mureb ◽  
Bernadine Donahue ◽  
Erik Sulman ◽  
Joshua Silverman ◽  
...  

Abstract INTRODUCTION: Stereotactic radiosurgery (SRS) is an accepted treatment for multiple brain metastases. However, the upper limit of the number of brain metastases over the course of care suitable for this approach is controversial. METHODS: From a review of our prospective registry, 48 patients treated with SRS for ≥ 25 brain metastases in either single or multiple sessions between 2013 and 2019 were identified. Patient, tumor, and treatments characteristics were evaluated. Clinical outcomes and overall survival (OS) were analyzed. RESULTS: Thirty-one females (64.6%) and 17 males (35.4%) with a median age of 56 years (25–91) were included. Primary diagnoses included lung (n=23, 47.9%), breast (n=13, 27.1%), melanoma (n=8, 16.7%), and other (n=4, 8.33%). Initial median GPA index was 2 (0.5–3). Nine patients (18.8%) had received whole brain radiation therapy (WBRT) prior to first SRS treatment, with a median dose of 35Gy (30–40.5Gy). Ten patients (20.8%) received WBRT after initial SRS, with a median dose of 30Gy (20-30Gy). Thus, only 19 patients (40%) ever received WBRT. Median number of radiosurgeries per patient was 3 (1–12). Median number of cumulative tumors irradiated was 31 (25–110). Median number of tumors irradiated at first SRS was 10 (1–35). Median marginal dose for the largest tumor per session was 16Gy (10-21Gy). Median SRS total tumor volume was 6.8cc (0.8–23.4). Median follow-up since initial SRS was 16 months (1–71). At present, 21 (43.7%) are alive. Median OS from the diagnosis of brain metastases was 31 months (2–97), and OS from the time of first SRS, 22 months (1–70). Median KPS at first SRS and last follow-up was the same (90). Sixty-three percent did not require a corticosteroid course. CONCLUSION: In selected patients with a large number of cumulative brain metastases (≥ 25), SRS is effective and safe. Therefore, WBRT may not be required in this population.


Neurosurgery ◽  
2016 ◽  
Vol 78 (6) ◽  
pp. 877-882 ◽  
Author(s):  
Jennifer C. Ho ◽  
Dershan Luo ◽  
Nandita Guha-Thakurta ◽  
Sherise D. Ferguson ◽  
Amol J. Ghia ◽  
...  

Abstract BACKGROUND: Removal of a pin during Gamma Knife stereotactic radiosurgery (GK-SRS) may be necessary to prevent collision and allow treatment. OBJECTIVE: To investigate outcomes after GK-SRS for treatment of brain metastases using a head frame immobilized to the skull with only 3 pins. METHODS: Between 2009 and 2014, we retrospectively reviewed the records of 1971 patients and identified 20 patients with multiple brain metastases treated with GK-SRS in which 1 anterior pin was removed immediately before treatment of a single posterior lesion. GK-SRS was also delivered to 116 other lesions in these 20 patients using the standard 4 pins during the same session, serving as an internal control for comparison. Endpoints included local control, dosimetric parameters, toxicity, and overall survival. RESULTS: The median number of lesions treated per session was 6 (range, 2-14). The lesions treated using 3 pins were located in the occipital lobe (n = 14) or the cerebellum (n = 6). Median follow-up was 12.3 months. There was 1 local failure involving a control lesion. Lesions treated using 3 pins had a lower prescription isodose line. GK-SRS of a lesion using 3 pins did not cause any clinical toxicities or increase in radiographic edema or hemorrhage. CONCLUSION: Treating posteriorly located brain metastases with GK-SRS using only 3 pins provided excellent local control and no difference in treatment toxicity, which may make it a safe and reasonable option for lesions that may otherwise be difficult to treat.


2015 ◽  
Vol 115 (2) ◽  
pp. 229-234 ◽  
Author(s):  
Hyun Kim ◽  
Peter Potrebko ◽  
Amanda Rivera ◽  
Haisong Liu ◽  
Harriet B. Eldredge-Hindy ◽  
...  

2015 ◽  
Vol 17 (suppl 5) ◽  
pp. v47.3-v47
Author(s):  
Christopher Grubb ◽  
Ashish Jani ◽  
Cheng-Chia Wu ◽  
Shumaila Saad ◽  
Yasir H. Qureshi ◽  
...  

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi211-vi211
Author(s):  
Shearwood McClelland III ◽  
Catherine Degnin ◽  
Yiyi Chen ◽  
Gordon Watson ◽  
Jerry Jaboin

Abstract INTRODUCTION For brain metastases, single-fraction stereotactic radiosurgery (SRS) spares appropriately chosen patients from the invasiveness of operative intervention and the permanent cognitive morbidity of whole brain radiation. SRS is delivered predominantly via two modalities: Gamma Knife, and linear accelerator (LINAC). The implementation of the American Tax Payer Relief Act (ATRA) in 2013 represented the first time limitations specifically targeting SRS reimbursement were introduced into federal law. The subsequent impact of the ATRA on SRS utilization in the United States (US) has yet to be examined. METHODS The National Cancer Data Base (NCDB) from 2010–2016 identified brain metastases patients from non-small cell lung cancer (NSCLC) throughout the US having undergone SRS. Utilization between GKRS and LINAC was assessed before (2010–2012) versus after (2013–2016) ATRA implementation. Utilization was adjusted for several variables, including patient demographics and healthcare system characteristics. RESULTS From 2012 to 2013, there was a substantial decrease of LINAC SRS in favor of GKRS overall (37% to 28%) and individually in both academic and non-academic centers. Over the three-year span immediately preceding ATRA implementation, 65.8% received GKRS and the remaining 34.2% receiving LINAC. In the four years immediately following ATRA implementation 68.0% received GKRS compared with 32% receiving LINAC; these differences were not statistically significant. CONCLUSIONS ATRA implementation in 2013 caused an initial spike in Gamma Knife SRS utilization, followed by a steady decline, similar to rates prior to implementation. These findings are indicative that the ATRA provision mandating Medicare reduction of outpatient payment rates for Gamma Knife to be equivalent with those of LINAC SRS had a significant short-term impact on the radiosurgical treatment of metastatic brain disease throughout the US. Such findings should serve as a reminder of the importance and impact of public policy on treatment modality utilization by physicians and hospitals.


2018 ◽  
Vol 149 ◽  
pp. 83
Author(s):  
K.G. Petras ◽  
I. Helenowski ◽  
R.A. Patel ◽  
J.R. Lurain ◽  
M.C. Tate ◽  
...  

2008 ◽  
Vol 109 (2) ◽  
pp. 259-267 ◽  
Author(s):  
Alberto Franzin ◽  
Alberto Vimercati ◽  
Piero Picozzi ◽  
Carlo Serra ◽  
Silvia Snider ◽  
...  

Object Treatment options for patients with brain metastasis include tumor resection, whole-brain radiation therapy, and radiosurgery. A single treatment is not useful in cases of multiple tumors, of which at least 1 is a cystic tumor. The purpose of this study was to assess the role of stereotactic drainage and Gamma Knife surgery (GKS) in the treatment of cystic brain metastasis. Methods Between January 2001 and November 2005, 680 consecutive patients with brain metastases underwent GKS at our hospital, 30 of whom were included in this study (18 males and 12 females, mean age 60.6 ± 11 years, range 38–75 years). Inclusion criteria were: 1) no prior whole-brain radiation therapy or resection procedure; 2) a maximum of 4 lesions on preoperative MR imaging; 3) at least 1 cystic lesion; 4) a Karnofsky Performance Scale score ≥ 70; and 5) histological diagnosis of a malignant tumor. Results Non–small cell lung carcinoma was the primary cancer in most patients (19 patients [63.3%]). A single metastasis was present in 13 patients (43.3%). There was a total of 81 tumors, 33 of which were cystic. Ten patients (33.3%) were in recursive partitioning analysis Class I, and 20 (66.6%) were in Class II. Before drainage the mean tumor volume was 21.8 ml (range 3.8–68 ml); before GKS the mean tumor volume was 10.1 ml (range 1.2–32 ml). The mean prescription dose to the tumor margin was 19.5 Gy (range 12–25 Gy). Overall median patient survival was 15 months. The 1- and 2-year survival rates were 54.7% (95% confidence interval 45.3–64.1%) and 34.2% (95% confidence interval 23.1–45.3%). Local tumor control was achieved in 91.3% of the patients. Conclusions The results of this study support the use of a multiple stereotactic approach in cases of multiple and cystic brain metastasis.


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