What Factors Predict The Response Of Larger Brain Metastases To Radiosurgery?Huai-che Yang1, Hideyuki Kano, MD, PhD2, L Dade Lunsford1, Ajay Niranjan, MCh2, John C. Flickinger, MD3, Douglas Kondziolka, MSc, MD21UPMC, Pittsburgh, USA 2Department of Neurological Surgery, University of Pittsburgh 3Department of Radiation Oncology, University of Pittsburgh Keywords: brain metastasis, radiosurgery, gamma knife, brain tumor, outcomeInteractive ManuscriptAsk Questions of this Manuscript: What is the background behind your study?Stereotactic radiosurgery (SRS) is an important management option for patients with brain metastases. What is the purpose of your study?To assess the potential role of SRS for larger metastatic brain tumors, we reviewed our recent experience Describe your patient group.Between 2004 and 2008, 70 patients with a metastatic brain tumor larger than 3 cm in maximum diameter underwent Gamma knife® SRS. Describe what you did.Patients underwent Gamma knife® SRS, thirty-three patients had received previous whole brain radiation therapy (WBRT) and 37 received only SRS. Describe your main findings.At a median first imaging follow-up of 2 months (range, 0.7-4.7 months) after radiosurgery, 29 (41%) tumors had more than a 50% volume reduction, 22 (31%) tumors had 10-50% volume reduction, 13 (19%) tumors were stable and six (9%) tumors were larger. We also evaluated brain edema using MRI T2 images In 11 patients (16%), the peritumoral edema volume was reduced by more than 50%, in 25 (36%) was reduced by 10-50%, in 21 (30%) was stable and in 13 (19%) was increased. Twenty (36%) discontinued corticosteroids by the time of first imaging follow-up. Because of persistent symptoms, seven patients (10%) required a craniotomy to remove the tumor. In univariate analysis, a better tumor volume reduction (>50%) was associated with a single metastasis (p=0.012), no previous WBRT (p=0.002), and a tumor volume < 16cc (p=0.002). The better peritumoral edema volume reduction (>50%) was associated with a single metastasis (p=0.024), no previous WBRT (p=0.05), and breast cancer histology (p=0.044). Describe the main limitation of this study.This is a retrospective study. Describe your main conclusion.Larger metastatic brain tumors responded favorably to SRS. Describe the importance of your findings and how they can be used by others.Tumor volume and edema responded better in patients who underwent SRS alone. Stereotactic radiosurgery (SRS) is an important management option for patients with brain metastases. To assess the potential role of SRS for larger metastatic brain tumors, we reviewed our recent experience Between 2004 and 2008, 70 patients with a metastatic brain tumor larger than 3 cm in maximum diameter underwent Gamma knife® SRS. Patients underwent Gamma knife® SRS, thirty-three patients had received previous whole brain radiation therapy (WBRT) and 37 received only SRS. At a median first imaging follow-up of 2 months (range, 0.7-4.7 months) after radiosurgery, 29 (41%) tumors had more than a 50% volume reduction, 22 (31%) tumors had 10-50% volume reduction, 13 (19%) tumors were stable and six (9%) tumors were larger. We also evaluated brain edema using MRI T2 images In 11 patients (16%), the peritumoral edema volume was reduced by more than 50%, in 25 (36%) was reduced by 10-50%, in 21 (30%) was stable and in 13 (19%) was increased. Twenty (36%) discontinued corticosteroids by the time of first imaging follow-up. Because of persistent symptoms, seven patients (10%) required a craniotomy to remove the tumor. In univariate analysis, a better tumor volume reduction (>50%) was associated with a single metastasis (p=0.012), no previous WBRT (p=0.002), and a tumor volume < 16cc (p=0.002). The better peritumoral edema volume reduction (>50%) was associated with a single metastasis (p=0.024), no previous WBRT (p=0.05), and breast cancer histology (p=0.044). This is a retrospective study. Larger metastatic brain tumors responded favorably to SRS. Tumor volume and edema responded better in patients who underwent SRS alone. Project Roles:
H. Yang (), H. Kano (), L. Lunsford (), A. Niranjan (), J. Flickinger (), D. Kondziolka ()
|
