Gamma surgery for intracranial metastases from renal cell carcinoma

OBJECT: The goal of this study was to evaluate the effectiveness and limitations of gamma surgery (GS) in the treatment of renal cell carcinoma that has metastasized to the brain. METHODS: The authors performed a retrospective analysis of a consecutive series of 21 patients with 37 metastatic brain deposits from renal cell carcinoma who were treated with GS at the University of Virginia from 1990 to 1999. Clinical data were available in all patients. No patient died of progression of intracranial disease or deteriorated neurologically following GS. Eight patients clinically improved. Follow-up imaging studies were available for 23 tumors in 12 patients. Nine patients did not undergo follow-up imaging. One patient lived 17 months and succumbed to systemic disease: no brain imaging was performed in this case. Another patient refused further imaging and lived 7 months. Seven patients lived up to 4 months after the procedure; however, their physicians did not require these patients to undergo follow-up imaging examinations because of their general conditions-all had systemic progression of disease. Of the 23 tumors that were observed posttreatment, one remained unchanged in volume, 16 decreased in volume, and six disappeared. No tumor progressed at any time, and there were no radiation-induced changes on follow-up imaging an average of 21 months after GS (range 3-63 months). CONCLUSIONS: Gamma surgery provides an alternative to surgical resection of metastatic brain deposits from renal cell carcinoma. Neurological side effects were seen in only one case; freedom from progression of disease was achieved in all cases.     

伽玛刀治疗血管母细胞瘤临床分析

目的 探讨伽玛刀(γ刀)对血管母细胞瘤的治疗作用。方法 应用γ刀治疗血管母细胞瘤17例。12例为单发肿瘤,5例为多发肿瘤,肿瘤总数29个;肿瘤直径6～55mm,平均16mm。照射肿瘤的中心剂量为21．0—50．0Gy,周边剂量为12．0—24．0Gy。结果 17例患者全部获随访,随访时间18—62个月,平均46个月。5例患者症状改善肿瘤缩小;5例症状无明显变化;3例分别于γ刀术后18、22、25个月死于肿瘤发展、开颅手术和肾癌;4例分别于γ刀术后3、4、29和48个月因症状加重开颅手术切除肿瘤。γ刀对血管母细胞瘤的局部控制率：1年为92％;2年为88％;3年为80％,4年为75％。结论 当肿瘤周边剂量为16．0—20．0Gy,γ刀能有效控制中小型实质性血管母细胞瘤,但长期疗效有待进一步随访观察。     

Stereotactic radiosurgery as a salvage treatment for recurrent skull base adenoid cystic carcinoma

Twelve patients (15 lesions) with recurrent skull base adenoid cystic carcinoma (ACC) were treated by Gamma Knife stereotactic radiosurgery (SRS). The tumor volume ranged from 2 to 103 ml (median 15 ml). Treatment was prescribed at the 40-60% isodose line and ranged from 10 to 18 Gy (median: 13.0 Gy). The median follow-up period was 18 months (range 3-55). Six patients were alive and 6 dead at the end of the follow-up period. Only 1 patient died from local tumor recurrence. Ten among 15 tumors treated by SRS decreased in size until the end of the follow-up period or the patients' death. Three remained unchanged in size. Two tumors initially regressed but then increased in size. In selected patients with recurrent skull base ACC, SRS can be considered as a salvage treatment with good local control.     

Risk of injury to cranial nerves after gamma knife radiosurgery for skull base meningiomas: experience in 88 patients.

OBJECT: In this study the authors sought to determine the neurological risks and potential clinical benefits of gamma knife radiosurgery for skull base meningiomas. METHODS: A consecutive series of 88 patients harboring skull base meningiomas were treated between 1990 and 1996 by using the Leksell gamma knife in a prospective clinical study that included a strict dose-volume protocol. Forty-nine patients had previously undergone surgery, and six had received external-beam radiotherapy. The median treatment volume was 10 cm3, and the median dose to the tumor margin was 16 Gy. The radiosurgical dosage to the optic nerve, the cavernous sinus, and Meckel's cave was calculated and correlated with clinical outcome. The median patient follow-up time was 35 months (range 12-83 months). Two tumors (2.3%) progressed after radiosurgery; the progression-free 5-year survival rate was 95%. At last follow-up review, 60 (68%) tumors were smaller and 26 (29.5%) remained unchanged. Clinical improvement (in vision, trigeminal pain, or other cranial nerve symptoms) occurred in 15 patients. Functioning optic nerves received a median dose of 10 Gy (range 1-16 Gy), and no treatment-induced visual loss occurred. Among nine patients with new trigeminal neuropathy, six received doses of more than 19 Gy to Meckel's cave. CONCLUSIONS: Gamma knife radiosurgery appeared to be an effective method to control the growth of most skull base meningiomas in this intermediate-term study. The risk of trigeminal neuropathy seemed to be associated with doses of more than 19 Gy, and the optic apparatus appeared to tolerate doses greater than 10 Gy. Considering the risks to cranial nerves associated with open surgery for comparable tumors, the authors believe that gamma knife radiosurgery is a useful method for the management of properly selected recurrent, residual, or newly diagnosed skull base meningiomas.     

Trigeminal schwannomas: results of gamma knife surgery in 37 cases

OBJECT: Information on outcomes of Gamma Knife surgery (GKS) for patients harboring trigeminal schwannomas is limited because these tumors are rare. The authors evaluated tumor control and functional outcomes in patients who underwent GKS for trigeminal schwannomas to clarify the efficacy of this treatment. METHODS: Forty-two patients with trigeminal schwannomas but no evidence of neurofibromatosis Type 2 were treated with GKS at Komaki City Hospital between November 1991 and December 2003. Of these, 37 patients were assessed. The mean tumor volume in these patients was 10 cm3. The mean maximum radiation dose directed to the tumor was 27.9 Gy and the mean dose directed to the tumor margin was 14.2 Gy. The mean follow-up period was 54 months. In four patients (11%) there was complete tumor remission; in 20 (54%) there was partial tumor remission; in eight (22%) the disease remained stable; and in five (14%) the tumor enlarged or uncontrollable facial pain developed with radiation-induced edema requiring resection. The actuarial 5- and 10-year tumor control rates were both 84%. With respect to functional outcomes, 40% of patients noted an improvement in their symptoms, and one patient experienced new symptoms despite good tumor control. CONCLUSIONS: Gamma Knife surgery was a safe and effective treatment for a select group of patients harboring trigeminal schwannomas. Large tumors that compress the brainstem and cause deviation of the fourth ventricle should first be removed surgically and any remnant should be treated by GKS.     

Long-term outcomes in patients with vestibular schwannomas treated using gamma knife surgery: 10-year follow up

OBJECT: Gamma knife surgery (GKS) has been a safe and effective treatment for vestibular schwannomas in both the short and long term, although less is known about long-term outcomes in the past 10 years. The aim of this study was to clarify long-term outcomes in patients with vestibular schwannomas treated using GKS based on techniques in place in the early 1990s. METHODS: Eighty patients harboring a vestibular schwannoma (excluding neurofibromatosis Type 2) were treated using GKS between May 1991 and December 1993. Among these, 73 patients were assessed; seven were lost to follow up. The median duration of follow up was 135 months. The mean patient age at the time of GKS was 56 years old. The mean tumor volume was 6.3 cm3, and the mean maximal and marginal radiation doses applied to the tumor were 28.4 and 14.6 Gy, respectively. Follow-up magnetic resonance images were obtained in 71 patients. Forty-eight patients demonstrated partial tumor remission, 14 had tumors that remained stable, and nine demonstrated tumor enlargement or radiation-induced edema requiring resection. Patients with larger tumors did not fare as well as those with smaller lesions. The actuarial 10-year progression-free survival rate was 87% overall, and 93% in patients with tumor volumes less than 10 cm3. No patient experienced malignant transformation. CONCLUSIONS: Gamma knife surgery remained an effective treatment for vestibular schwannomas for longer than 10 years. Although treatment failures usually occurred within 3 years after GKS, it is necessary to continue follow up in patients to reveal delayed tumor recurrence.     

Radiologic and histopathologic changes after Gamma Knife radiosurgery for acoustic schwannoma

Gamma knife radiosurgery (GKRS) is a widely used treatment option for acoustic schwannomas, 3 cm in diameter or less. Between May 1990 and February 1998, 102 acoustic tumors in 101 patients were treated with GKRS. There are 77 patients with a follow-up period of more than six months (mean 55, range 7 to 90 months). Seventy (91%) of these tumors have remained unchanged or reduced in volume. After GKRS there was an increase in volume in seven cases. In four the volume increase affected solid tumour. Among these, three patients were in stable condition and are being observed. One of these patients developed brain stem compression symptoms and was operated. In another three cases, cysts with multiple septa developed medial to the tumor and compressed the brain stem and fourth ventricle, thus necessitating post-GKRS surgery. In these three patients, MRI had shown loss of central contrast enhancement followed by its return. Histological findings at surgery before and after GKRS were compared for these four tumours. In spite of the MRI changes, there were no definite histological findings after GKRS which could be attributed to radiation induced changes. The development of cysts occurred after the treatment of larger tumors.     

Radiosurgery for facial schwannoma

OBJECT: The aim of this study was to evaluate the results of radiosurgery in patients with facial schwannoma. METHODS: The study population consisted of 14 patients, six men and eight women, with a mean age of 45.4 years. Most of the patients had presented with facial palsy (11 of 14 patients) and/or hearing disturbance (nine of 14 patients). Prior treatment in nine of the 14 cases consisted of tumor resection or tumor biopsy. Tumor volume ranged from 0.98 to 20.8 cm3, and the mean tumor volume was 5.5 cm3. The mean maximum radiation dose and mean tumor margin dose used for radiosurgery were 24.0 and 12.9 Gy, respectively. During the mean follow-up period of 31.4 months (range 12-120 months), 10 of the tumors shrank and four remained unchanged. The tumor response and tumor control rates were 57 and 100%, respectively. None of the tumors progressed, and no subsequent resection was required. Facial nerve function improved in five cases, remained unchanged in eight, and became worse in one. There was no change in hearing function in any of the patients. Complications developed in only one patient: the onset of facial palsy immediately after treatment, which subsequently recovered to House-Brackmann Grade III. CONCLUSIONS: In summary, radiosurgery was found to be a very useful method of treating facial schwannoma, for both tumor control and functional control. Radiosurgery should therefore be the treatment of first choice for facial schwannomas.     

Gamma knife radiosurgery for skull base meningiomas: the treatment results and patient satisfaction expressed in answers to a questionnaire

Skull base meningiomas can be treated by radiosurgery with low morbidity. We evaluated the effectiveness of gamma knife radiosurgery for skull base meningiomas. We also evaluated patient satisfaction through answers to a questionnaire. We treated 77 patients of skull base meningiomas using gamma knife radiosurgery from January 1994 to June 1998. Among these patients, 73 patients were able to be followed up from 6 to 60 months (average 25 months). The diagnosis was made by operations on 39 patients (53%), and on magnetic resonance imagings in 34 patients (47%). 21 patients (28.7%) had residual tumors after operations and 18 patients (24.3%) had recurrence after operations. 40% of neurological deficits occurred after previous operations and 20% of the patients were asymptomatic. The locations of the tumors were mainly the cavernous sinus region in 35 patients and the petroclival region in 20 patients. The tumor sizes were 8.6 to 58.3 mm (average 24.7 mm) and five cases of tumors with a mean diameter above 40 mm were treated by two-staged radiosurgery. Treatment volume was 0.3 to 31 ml (average 9.8 ml). The treatment dose was 8 to 16 Gy (average 11.2 Gy) at the tumor margin. The tumor decreased in size in 50 patients (68%) and was unchanged in 20 patients (28%) and we were able to achieve 96% tumor growth control. The clinical symptoms improved in 22 patients (30.1%) and were unchanged in 47 patients (64.4%) and only 4 patients (5.5%) showed deterioration. 50 patients (68%) felt clinical improvement and only 3 patients (4%) sensed deterioration. 58 patients (79%) were able to continue their previous work. Gamma knife radiosurgery has a very low morbidity rate and enables good tumor control, and patients with skull base meningiomas express satisfaction with the treatment results.     

Gamma knife radiosurgery for intraventricular meningiomas

Purpose  Intraventricular meningiomas are relatively rare tumors that may benefit from stereotactic radiosurgery as a minimally invasive treatment strategy. We report our experience using gamma knife radiosurgery (GKR) for intraventricular meningiomas. Methods  Over a 16-year period, we identified 9 patients with intraventricular meningiomas who were eligible for GKR out of a total management experience of 1,045 patients. The mean patient age was 51 years (range, 14 to 81). Three had radiosurgery for recurrent tumors after prior resection, and GKR was used as an adjunctive after subtotal resection in 1 patient. In the other 5 patients, GKR was used as primary management. Two had a diagnosis of meningioma confirmed by biopsy. The median tumor volume at GKR was 3.9 cc (range, 0.8–11.8). A median margin dose of 16.0 Gy (range, 14.0–22.5) was delivered to the tumor margin. Results  The average follow-up was 64 months. None of the patients developed hydrocephalus or treatment-related morbidity. The progression-free periods after radiosurgery varied from 7 to 160 months (mean, 60). Four tumors regressed and 2 remained unchanged. Three patients showed delayed tumor progression. Meningioma growth control was obtained in 7 out of 9 patients, but 1 patient required two radiosurgical procedures. Conclusions  Gamma knife radiosurgery may be an additional minimally invasive management option for small intraventricular meningiomas in patients who either fail or are unsuitable for resection.     

Low-dose radiosurgery for meningiomas

Gamma Knife radiosurgery is an effective treatment for meningiomas. However, it may be difficult to deliver what is currently considered an optimal dose, especially if the tumor is large or adjacent to critical structures. Eleven cases are presented with a follow-up of more than 12 months where the margin dose did not exceed 10 Gy. The mean age was 48.8 years. The mean follow-up period was 35.7 months (range 21 to 57 months). The mean volume of the tumors was 9.4 cm3 (range 1.6 to 28.9 cm3). The margin dose was less than 10 Gy in all 11 cases, due to a large volume in two cases. Four tumors were close to the visual pathways. Five tumors were close to the brain stem. Imaging follow-up showed that four tumors had shrunk after radiosurgery. The remaining seven cases remained unchanged. There was no tumor growth after radiosurgery. A transient oculomotor palsy was observed in two cases after radiosurgery. It is suggested that Gamma Knife radiosurgery using lower dosage than usual is one of the options for the treatment of meningioma.     

Gamma Knife Radiosurgery for Glomus Jugulare Tumours

Summary  The aim of this clinical study was to determine the tumour control rate, clinical outcome and complication rate following gamma knife treatment for glomus jugulare tumours. Between May 1992 and May 1998, 13 patients with glomus tumours underwent stereotactic radiosurgical treatment in our department. The age of these patients ranged from 21 to 80 years. The male : female ratio was 2 : 11. Six patients had primary open surgery for partial removal or recurrent growth and subsequent radiosurgical therapy. Radiosurgery was performed as primary treatment in 7 cases. The median tumour volume was 6,4 cm³ (range: 4,6–13,7 cm³). The median marginal dose applied to an average isodose volume of 50% (30–50%) was 13,5 Gy (12–20 Gy). In 10 patients, a total of 48 MRI and CT follow-up scans were available. The remaining three patients have been excluded from the postradiosurgical evaluation since the observation time (t<12 months) was too short or patients were lost to follow up. The median interval from Gamma Knife treatment to the last radiological follow-up was 37,6 months (5–68 months). In 4 patients (40%) decreased tumour volumes were observed and in 6 cases (60%) the tumour size remained unchanged. Neurological follow-up examinations revealed improved clinical status in 5 patients (50%), a stable neurological status in 5 patients (50%) and no complications occurred. According to our preliminary experience Gamma Knife radiosurgery represents an effective treatment option for glomus jugulare tumours.     

Unstable thoracolumbar and lumbar burst fractures treated with the AO fixateur interne.

Twenty-five consecutive patients with unstable thoracolumbar and lumbar burst fractures were surgically treated with the AO Fixateur Interne (Synthes USA, 1690 Russell Rd., Paoli, PA). Indications for surgery included a progressive neurologic deficit, spinal canal compromise greater than 50%, vertebral body collapse greater than 50%, or sagittal angulation greater than 20 degrees. Twenty males and five females ranging in age from 16 to 60 years (average 31) were treated surgically and prospectively followed. Twenty-one fractures occurred at the thoracolumbar junction (T10-L2) and 4 in the lumbar spine (L3-5). Twenty-four patients were followed for a minimum of 12 months, ranging from 12 to 38 months (average 22); one patient was lost to follow-up after 1 month postoperatively. Preoperatively, 12 patients had partial neurologic deficits; postoperatively, 11 improved at least 1 Frankel grade. Preoperatively, the 12 patients with partial neurologic deficits averaged 45 points (range 24-49) on the lower extremity motor index scale. After surgery, these patients improved an average of five points (range 1-23) on the motor index scale. Both patients with complete spinal cord injuries remained unchanged neurologically postoperatively; no patients deteriorated neurologically after surgery. The average preoperative sagittal kyphosis at the fracture site was +16 degrees (range +10 degrees to +31 degrees); the immediate postoperative sagittal angular correction averaged -4 degrees (lordosis) and ranged from +12 degrees (kyphosis) to -26 degrees (lordosis). At last follow-up, the sagittal angular correction remained unchanged in three patients and decreased in 21 patients to an average of +5 degrees (range +37 degrees to -14 degrees).(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-term outcomes of Gamma Knife surgery for cavernous sinus meningioma

OBJECT: The aim of this study was to evaluate long-term outcomes, including tumor control and neurological function, in patients with cavernous sinus meningiomas treated using Gamma Knife surgery (GKS). METHODS: One hundred fifteen patients with cavernous sinus meningiomas, excluding atypical or malignant meningiomas, were treated with GKS between 1991 and 2003. Forty-nine patients (43%) underwent GKS as the initial treatment. The mean tumor volume was 14 cm3, and the mean maximum and margin doses applied to the tumor were 27 and 13 Gy, respectively. The median follow-up period was 62 months. During the follow-up, 111 patients were able to be evaluated with neuroimaging. RESULTS: The actuarial 5- and 10-year progression-free survival rates were 87 and 73%, respectively. Similarly, the actuarial 5- and 10-year focal tumor control rates were 94 and 92%, respectively. Regarding functional outcomes, 43 patients (46%) experienced some degree of improvement, 40 (43%) remained stable, and 11 (12%) had worse preexisting or newly developed symptoms. Patients who underwent GKS as the initial treatment experienced significant improvement of their symptoms (p = 0.006). CONCLUSIONS: Gamma Knife surgery is a safe and effective treatment over the long term in selected patients with cavernous sinus meningiomas. Tumor progression is more likely to occur from the lesion margin outside the treatment volume. In small to medium-sized tumors, GKS is an excellent alternative to resection, preserving good neurological function. For relatively large-sized tumors, low-dose radiosurgery (< or = 12 Gy) is acceptable for the prevention of tumor progression.     

Gamma Knife radiosurgery for functioning pituitary microadenoma

Transsphenoidal microsurgery remains the treatment of choice for pituitary microadenomas One hundred and six patients were treated with Gamma Knife radiosurgery (GKRS) for pituitary adenomas, and of these, 23 patients (1 male, 22 female) had microadenomas. Twenty-two of these patients were followed up and endocrinological tests were available for 15 of these 22. Thirteen of these 15 had prolactinomas, while the remaining 2 had acromegaly. The follow-up period was from 3 to 26 months (median 12 months). The mean age was 33.6 years (range 21 to 60 years). The mean maximum tumor dose was 35.7 Gy and the mean margin dose was 22 Gy. Serum prolactin (PRL) was normalized in three patients, decreased in eight and unchanged in two. The growth hormone (GH) secretion in the acromegalic patients has remained unchanged through the follow-up period. Thus, GKRS is a valuable adjuvant to transsphenoidal microsurgery for patients with pituitary microadenomas.     

首选溴隐亭治疗侵袭性巨大泌乳素腺瘤的综合治疗

目的观察首选溴隐亭治疗侵袭性巨大泌乳素腺瘤（IGPs）综合治疗的远期疗效。方法符合IGPs诊断标准的患者34例,均首选溴隐亭进行治疗,其中11例同时配合放疗。服药期间根据肿瘤缩小后的残留部位、有无继续显著缩小、有无耐药等情况决定是否手术或立体定向放射外科治疗或二者联合应用。术后继续以小剂量溴隐亭维持治疗。结果平均随访33．6个月,33例患者症状显著改善,1例放疗后视力改善不明显。肿瘤体积平均缩小91．4％,泌乳素平均下降约97．1％,睾酮下降、皮质醇功能低下分别由治疗前的17例、10例降至6例、6例。溴隐亭治疗期间出现脑脊液鼻漏2例,1例自行缓解,1例行经蝶、开颅联合入路切除肿瘤、修补瘘口;4例出现不同程度的耐药现象。结论IGPs应首选药物治疗,部分患者仅通过药物治疗即可达到影像学上肿瘤消失的目的,大部分患者需辅助经蝶手术、立体定向放射外科治疗,可以明显缩短治疗时间、减少药物的用量甚至停药,但要慎行放疗。