Gamma Knife Radiosurgery for Brainstem Metastasis

Abstract

small case series for the management of brainstem metastases using Gamma Knife Radiosurgery (GKRS) 12,16,18,22,26,35) . The present study assessed outcomes following our use of GKRS for the management of brainstem metastasis, and we investigated the effect of treatment on tumor size and survival time. MATERIALS AND METHODS Patient characteristicsFrom November 1992 to June 2010, a total of 32 patients underwent GKRS for local control of brainstem metastasis at our institute. The clinical characteristics of the 32 patients are summarized in Table 1. The study population consisted of 23 men and 9 women, with a mean age of 56.1 years (range, 39-73). The primary malignancy was lung cancer in 21 patients, breast cancer in 3, renal cell cancer in 2, prostate cancer in 2, and hepatocellular carcinoma, colorectal cancer in 1, gastric cancer in 1, and melanoma in 1. Fourteen patients had score of more than 70 on the Karnofsky performance status (KPS), and 18 had scores of less than 70. Lesions were located in the pons in 23 patients, the midbrain in 6 and the medulla oblongata in 3 patients. Fifteen patients presented with brainstem signs which INTRODUCTIONMetastasis to the brain is a frequent complication of malignant tumors of the lung, breast, kidney, and of malignant melanoma 2) . Metastatic brain lesions are estimated to eventually develop in 15 to 40% of patients with cancer 31) , and autopsy studies show brain metastases in 24% of cancer patients. However, brainstem metastases are uncommon, and account for only 3 to 5% of all brain metastases 8,17,30) . Brainstem metastases are generally not treated surgically due to the risk of causing neurological damage. Whole brain radiation therapy (WBRT) and stereotactic radiosurgery have been reported to provide benefits in brain metastases patients 3,4,9,10,14,19,29) . However, the benefits of such treatment in brainstem metastasis patients remain unclear.Since the first report of Huang et al. series 15) , there were some Department of Neurosurgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaObjective : Brainstem metastases are rarely operable and generally unresponsive to conventional radiation therapy or chemotherapy. Recently, Gamma Knife Radiosurgery (GKRS) was used as feasible treatment option for brainstem metastasis. The present study evaluated our experience of brainstem metastasis which was treated with GKRS. Methods : Between November 1992 and June 2010, 32 patients (23 men and 9 women, mean age 56.1 years, range 39-73) were treated with GKRS for brainstem metastases. There were metastatic lesions in pons in 23, the midbrain in 6, and the medulla oblongata in 3 patients, respectively. The primary tumor site was lung in 21, breast in 3, kidney in 2 and other locations in 6 patients. The mean tumor volume was 1,517 mm 3 (range, 9-6,000), and the mean marginal dose was 15.9 Gy (range, 6-23). Magnetic Resonance Imaging (MRI) was obtained every 2-3 months following GKRS. Follow-up MRI was possible in 24 patients at a mean follow-up durat...

Medullary metastasis of a malignant peripheral nerve sheath tumor: A case report

“…Smalley et al (13) reported a median survival time of 11.7 months following resection of solitary brain metastases. Generally, brainstem metastases are not treated with conventional neurosurgery due to the risk of neurological damage (9,10), and Gamma Knife surgery is typically considered for brainstem metastasis (9) Gamma knife surgery exhibits a local control rate of 83-94% with a median survival time of 7-12 months (10). In the present case, gamma knife surgery may have been an appropriate treatment for tumor control.…”

The role of stereotactic radiosurgery in the management of secondary pontine tumors

“…During 1999-2013, nine patients' series [4,[6][7][8][10][11][12][13][14] with brainstem metastases treated with SRS (GKRS) were reported. The samples of these studies varied between 25-200 patients and the number of irradiated lesions ranged from 26 to 222 tumors.…”

“…Its management includes standard radiation and chemotherapy, while surgical resection is not a routine procedure due to its high risks. [4,6,7] For these patients SRS (GKRS) is nowadays used as a feasible treatment option and is considered as a treatment modality expected to achieve a radical cure. [7,8] Furthermore, GKRS is an effective therapy (a non-invasive alternative to surgery) for primary brainstem tumors.…”

“…[4,6,7] For these patients SRS (GKRS) is nowadays used as a feasible treatment option and is considered as a treatment modality expected to achieve a radical cure. [7,8] Furthermore, GKRS is an effective therapy (a non-invasive alternative to surgery) for primary brainstem tumors. [9] The pons is the common-est location of brainstem metastases (primarily from lung cancer), with a frequency ranging from 51.85% to 79.25% (see Table 1).…”

“…[9] The pons is the common-est location of brainstem metastases (primarily from lung cancer), with a frequency ranging from 51.85% to 79.25% (see Table 1). [4,[6][7][8][10][11][12][13][14] The purpose of this review is to explore the role of radiosurgery in the management of pontine metastases. Huang et al [4] 1999 77.77…”