Yoo Tae Won, Park Eun Suk, Kwon Do Hoon, Kim Chang Jin
Department of Neurosurgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
J Korean Neurosurg Soc. 2011 Oct;50(4):299-303. doi: 10.3340/jkns.2011.50.4.299. Epub 2011 Oct 31.
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.
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 duration of 12.0 months (range, 1-45). Kaplan-Meier survival analysis was used to evaluate the prognostic factors.
Follow-up MRI showed tumor disappearance in 6, tumor shrinkage in 14, no change in tumor size in 1, and tumor growth in 3 patients, which translated into a local tumor control rate of 87.5% (21 of 24 tumors). The mean progression free survival was 12.2 months (range, 2-45) after GKRS. Nine patients were alive at the completion of the study, and the overall mean survival time after GKRS was 7.7 months (range, 1-22). One patient with metastatic melanoma experienced intratumoral hemorrhage during the follow-up period. Survival was found to be associated with score of more than 70 on Karnofsky performance status and low recursive partitioning analysis class (class 1 or 2), in terms of favorable prognostic factors.
GKRS was found to be safe and effective for management of brainstem metastasis. The integral clinical status of patient seems to be important in determining the overall survival time.
脑干转移瘤很少能进行手术，且通常对传统放疗或化疗无反应。最近，伽玛刀放射外科手术（GKRS）被用作治疗脑干转移瘤的一种可行选择。本研究评估了我们用GKRS治疗脑干转移瘤的经验。
在1992年11月至2010年6月期间，32例患者（23例男性和9例女性，平均年龄56.1岁，范围39 - 73岁）接受了GKRS治疗脑干转移瘤。分别有23例患者的转移瘤位于脑桥，6例位于中脑，3例位于延髓。原发肿瘤部位为肺癌21例，乳腺癌3例，肾癌2例，其他部位6例。平均肿瘤体积为1517立方毫米（范围9 - 6000），平均边缘剂量为15.9 Gy（范围6 - 23）。GKRS后每2 - 3个月进行一次磁共振成像（MRI）检查。24例患者可行随访MRI，平均随访时间为12.0个月（范围1 - 45个月）。采用Kaplan - Meier生存分析评估预后因素。
随访MRI显示6例肿瘤消失，14例肿瘤缩小，1例肿瘤大小无变化，3例肿瘤生长，局部肿瘤控制率为87.5%（24个肿瘤中的21个）。GKRS后平均无进展生存期为12.2个月（范围2 - 45个月）。研究结束时9例患者存活，GKRS后的总体平均生存时间为7.7个月（范围1 - 22个月）。1例转移性黑色素瘤患者在随访期间发生瘤内出血。就有利的预后因素而言，生存与卡氏功能状态评分超过70分及低递归分区分析类别（1类或2类）相关。
发现GKRS治疗脑干转移瘤安全有效。患者的整体临床状况似乎对确定总生存时间很重要。
