Interstitial irradiation with stereotactically implanted I-125 seeds for the treatment of cerebral glioma

Owing to its low rate of side effects and its high efficacy, interstitial irradiation with low-activity seeds should be the first therapeutic step in small (maximal diameter 40 mm), well-circumscribed, low-grade gliomas affecting the brain stem, other midline structures, or eloquent cerebral areas. In anaplastic gliomas, a therapeutic schedule using low-activity seeds and combining interstitial irradiation with radiotherapy (reduced boost dose of 15-30 Gy) seems to be more effective than interstitial irradiation alone. Compared with interstitial irradiation with high-activity seeds, this combined irradiation schedule caused no space-occupying radiation necrosis. Thus, it can be recommended as up-front treatment in patients with small (maximal diameter <40 mm) inoperable anaplastic gliomas. The use of high-activity I-125 seeds and interstitial irradiation at comparably high dose rates, integrating a small penumbra of normal brain tissue into the treatment volume, improved survival significantly in patients with primary highly malignant gliomas. In patients with recurrent tumors, the same treatment schedule did not substantially prolong survival compared with results obtained after resection plus radiotherapy. Owing to the high frequency of space-occupying radiation necrosis (40-60%), this schedule is only applicable in surgically accessible tumors. The application of low-activity I-125 seeds (in primary glioblastomas in combination with radiotherapy, in recurrent tumors without radiotherapy) yielded a median survival comparable with conventionally treated patients. There was no need for reoperation because of radiation necrosis. Thus, this treatment schedule is useful in both operable and surgically inaccessible glioblastomas.     

Review of radiosurgery of pineal parenchymal tumors. Long survival following 125-iodine brachytherapy of pineoblastomas in 2 cases.

OBJECTIVE: The aim of the present work is to report the volumetric changes of tumor in two pineoblastoma patients treated with stereotactic interstitial irradiation and to present a review on radiosurgery of pineal parenchymal tumors. METHODS: Two of our patients with pineoblastoma were treated with CT and image-fusion guided 125-iodine brachytherapy. The tumor volumes were determined with outlined contours on planning and control CT/MRI images and were compared. RESULTS: Until January 2006, there were 61- and 58-month follow-up periods in the two cases. 56 and 53 months after irradiation the MRI images showed significant tumor shrinkage. In case 1 tumor volume was 0.76 cm (3) on the last control MRI image, compared to the 2.87 cm (3) at the time of interstitial irradiation, which means 73% shrinkage. In case 2, tumor volume measured with the last control MRI examination was 0.29 cm (3), which represents 77% shrinkage of the original tumor volume. In both Cases 1 and 2, PET examinations using (11)C-methionine showed no active tumor mass 56 and 53 months following brachytherapy. CONCLUSION: Two successful treatments of pineoblastoma are reported. The interstitial irradiation of the tumors decreased their volumes significantly. The CT and image fusion-guided 125-iodine stereotactic brachytherapy can be planned well dosimetrically and is surgically precise.     

Interstitial brachytherapy for low-grade cerebral gliomas: Analysis of results in a series of 36 cases

Summary The results obtained with interstitial brachytherapy in thirty-six low-grade cerebral gliomas (2 pilocytic astrocytomas, 23 astrocytomas and 11 oligodendrogliomas) are reported (mean follow-up: 75 months, range 37–159). All tumours were situated in locations which did not call for surgical removal as the treatment of choice. Their volume ranged from 4 to 82 cc (m=32); the Karnofsky performance status (KPS) of the treated patients lay between 0.60 and 0.90.The sources utilized (Iridium-192 in 32 cases and Iodine-125 in 4) were implanted permanently in 22 patients and temporarily in 14, using the Talairach stereotactic apparatus. The mean peripheral dose was 89.7 Gy for the permanent implants and and 42.8 Gy with a rate of 32.05 cGy/h for the temporary implants. External beam irradiation was added for tumour volumes greater than 35 cc (19 cases) on a second target volume extending 2 cm beyond the tumoural borders treated with interstitial irradiation.The survival estimates for the entire group showed a probability of 82.9% at 60 months, of 56.8% at 96, 39.4% at 120 (m.s.t.: 112 months). The quality of life in the treated patients was satisfactory, KPS never falling below a mean score of 0.70. The extent of the target volume turned out to be the most significant factor influencing survival at the multivariate analysis. Severe neurological impairment due to radionecrosis occurred in 4 patients (11%), three of them requiring surgical decompression. Target volume and radiation dose showed a direct correlation with the risk of radionecrosis at the regression analysis, the critical values being 35 cc and 100 Gy (permanent implants) or 50 Gy (42 cGy/h, temporary implants) respectively. The analysis of the results indicates that, even though many questions still remain open, brachytherapy can represent a valid alternative to surgery for tumours not suitable for surgical removal.Study partially supported by a grant from the Italian Ministry of University and of Scientific and Technological Research.     

Permanent iodine-125 interstitial radiation therapy in the treatment of non-glioblastoma multiforme high-grade gliomas

BACKGROUND: This study evaluates prognostic factors influencing survival outcomes for 60 patients with permanent iodine-125 implants in the primary treatment of non-glioblastoma multiforme (GBM) high-grade gliomas. METHODS: Stereotactic treatment planning aimed to encompass the contrast-enhancing rim of the tumor visualized by CT, with an initial dose rate of 0.05 Gy/h with 125I, delivering 100 Gy at 1 year and 103.68 Gy at infinity. Survival was evaluated using the Kaplan-Meier method for univariate analysis and the Cox regressional method for multivariate analysis. In addition to the implant, 34 patients received external radiation therapy (5,000-6,000 cGy) before the implant; 13 patients were implanted without additional external beam radiation, and 13 patients underwent external radiation therapy before implant placement. RESULTS: With a mean follow-up of 77.6 months (range 3.5-164 months), 1-, 3-, 5- and 10-year survival were 86.7% (+/-0.05%), 60% (+/-0.07%), 50% (+/-0.07%) and 45.7% (+/-0.7%), respectively. The median survival time was 57 months. Second surgery was performed following the implant in 19 patients. Findings were tumor recurrence in 11 patients (22.5%), radiation necrosis in 7 patients (14.3%) and brain abscess in 1 patient (2%). Age, sex, tumor location, side of brain, tumor volume, Karnofsky score and neurological status were correlated with survival outcome. Favorable prognostic factors were age younger than 45 years, superficial tumor location and preoperative Karnofsky score greater than 70. RPA classification was used to define this group of patients. In RPA classes I and II (n = 43), 1-year survival was 93%, while 3-, 5- and 10-year survival was 67.4, 60.5 and 55.5%, respectively, and median survival time was 91 months. In RPA class III (n = 7), 1-year survival was 71.4%, while 3- and 5-year survival was 42.9 and 28.6%, respectively, and median survival time was 47 months. In RPA class IV (n = 10), 1-year survival was 60%, while 3-, 5- and 10-year survival was 50, 22.2 and 11.1%, respectively, and median survival time was 37 months. CONCLUSION: Brachytherapy with permanent implant of 125I appears promising in the treatment of primary non-GBM malignant gliomas. It improved survival time and reduced the incidence of complications and provided good quality of life. In order to further confirm these results, multicenter randomized prospective studies are needed. RPA analysis is a valid tool to define prognostically distinct survival groups. In this study, 2-year survival and median survival time were improved in all prognostic classes. This would suggest that selection bias alone does not account for the survival benefit seen with 125I implants. Further randomized studies with effective stratification are needed.     

Permanent Iodine-125 Implants in the Treatment of Low-Grade Gliomas

We report a retrospective study on the use of the permanent iodine-125 (¹²⁵I) implants in the management of low-grade gliomas. From July 1988 to July 1997, 16 patients with low-grade gliomas underwent permanent ¹²⁵I implants in the management of their lesions. There were 7 males and 9 females ranging in age from 4 to 48 years (mean 19). The location was in the cerebral hemisphere in 7 patients, brainstem in 5 patients and thalamus/basal ganglia in 4 patients. Prior to brachytherapy, 9 patients underwent surgical resection and 7 patients underwent stereotactic biopsy procedures. Fourteen patients were treated as part of the initial management and 2 were recurrent. The histological diagnosis was: 9 WHO grade II astrocytomas, 3 oligodendrogliomas, 2 gemistocytic astrocytomas, 1 pilocytic astrocytoma, and 1 ependymoma. The tumor volume ranged from 0.7 to 33.4 cc (mean 8.4). Stereotactic treatment planning was used to encompass the contrast-enhancing rim of the tumor visualized by computerized tomography with an initial dose rate of 0.05 Gy/hour with ¹²⁵I. The total activity ranged from 0.8 to 20.5 mCi. With a median follow-up period of 35 months (range, 4–105 months), the 2- and 5-year survival rates were 93.7% and 87.5%, respectively. Three patients underwent reoperation after implants, two of three had recurrent disease, and one had radiation necrosis. Permanent ¹²⁵I implants appear to be safe and effective as a part of the multimodality management of low-grade gliomas.     

Permanent I Interstitial Radiation Therapy in the Treatment of Non-GBM High-Grade Gliomas

This study evaluates prognostic factors influencing survival outcomes for 50 patients with permanent¹²⁵ iodine-125 implants in the primary treatment of non-GBM high-grade gliomas. Stereotactic treatment planning aimed to encompass the contrast-enhancing rim of the tumor visualized by CT, with an initial dose rate of 0.05 Gy/hour with ¹²⁵I, delivering 100 Gy at 1 year and 103.68 Gy at infinity. Survival was evaluated using the Kaplan–Meier method for unvariate analysis and the Cox regressional method for multivariate analysis. In addition to the implant, 31 patients received external radiation therapy (5000 to 6000 cGy) before the implant; 10 patients were implanted without additional external beam radiation, and 9 patients underwent external radiation therapy before implant placement. With a mean follow-up of 40.76 months (range 3.47–87 months); 1–, 3–, and 5-year survival were 78.5% (± .05%), 58.7% (± .07%), and 56.2% (± .07%) respectively. Since 56.2% of the patients were alive at 5 years, median survival has not been reached yet. Second surgery was performed following the implant in 19 patients. Findings were tumor recurrence in 11 patients (22.5%), radiation necrosis in 7 patients (14.3%), and brain abcess in 1 patient (2%). Age, sex, tumor location, side of brain, tumor volume, Karnofsky, and neurological status were correlated with survival outcome. Favorable prognostic factors were age younger than 45 years, superficial tumor location, and preoperative Karnofsky greater than 70. Surgical treatment of patients with non-GBM high grade gliomas combined with external beam radiation and permanent ¹²⁵I implants represent a valuable alternative for the treatment of patients with malignant gliomas, allowing patients good quality of life and long survival.     

Recurrent Malignant Gliomas Treated with Radiosurgery

The inability to control malignant glioma results in a high incidence of local failure and poor survival. Focal therapy such as radiosurgery permits delivery of a high dose of radiation with moderate toxicity. This report summarizes the outcome of patients with recurrent malignant glioma treated with radiosurgery at University of Wisconsin Hospital, between January 1989 and December 1997, when 30 patients were treated radiosurgically. All patients had undergone and failed external beam radiotherapy (median dose of 59.4 Gy) prior to radiosurgery. All recurrences were detected by clinical deterioration and confirmed by radiographic progression. No patient was treated for radiographic progression only in the context of a screening protocol. Eight out of 30 patients underwent subtotal resection prior to radiosurgery and 3 received chemotherapy along with radiosurgery. Radiosurgery was delivered in a single fraction using a modified linear accelerator. The median tumor volume was 7.2 cm³ (range 0.42–35.1 cm³) and the median minimal tumor dose was 12 Gy at the 50–80% isodose line. Median follow-up is 70 months. The median overall survival is 8 months; the 1- and 2-year survival rates are 20% and 9%, respectively. For patients with an initial diagnosis of non-glioblastoma, the median survival is 11 months and for those with glioblastoma the median survival is 7 months. The median progression-free survival is 4 months for the entire cohort, 5 months for nonglioblastoma, and 3 months for glioblastoma. The 1-year actuarial reoperation rate after radio-surgery is 7.6%. Radiosurgery for recurrent malignant glioma may improve short-term survival for selected patients with a lower reoperation rate than brachytherapy.     

Brain metastases treated with radiosurgery alone: an alternative to whole brain radiotherapy?

OBJECTIVE: Whole brain radiotherapy (WBRT) provides benefit for patients with brain metastases but may result in neurological toxicity for patients with extended survival times. Stereotactic radiosurgery in combination with WBRT has become an important approach, but the value of WBRT has been questioned. As an alternative to WBRT, we managed patients with stereotactic radiosurgery alone, evaluated patients' outcomes, and assessed prognostic factors for survival and tumor control. METHODS: One hundred seventy-two patients with brain metastases were managed with radiosurgery alone. One hundred twenty-one patients were evaluable with follow-up imaging after radiosurgery. The median patient age was 60.5 years (age range, 16-86 yr). The mean marginal tumor dose and volume were 18.5 Gy (range, 11-22 Gy) and 4.4 ml (range, 0.1-24.9 ml). Eighty percent of patients had solitary tumors. RESULTS: The overall median survival time was 8 months. The median survival time in patients with no evidence of primary tumor disease or stable disease was 13 and 11 months. The local tumor control rate was 87%. At 2 years, the rate of local control, remote brain control, and total intracranial control were 75, 41, and 27%, respectively. In multivariate analysis, advanced primary tumor status (P = 0.0003), older age (P = 0.008), lower Karnofsky Performance Scale score (P = 0.01), and malignant melanoma (P = 0.005) were significant for poorer survival. The median survival time was 28 months for patients younger than 60 years of age, with Karnofsky Performance Scale score of at least 90, and whose primary tumor status showed either no evidence of disease or stable disease. Tumor volume (P = 0.02) alone was significant for local tumor control, whereas no factor affected remote or intracranial tumor control. Eleven patients developed complications, six of which were persistent. Nineteen (16.5%) of 116 patients in whom the cause of death was obtained died as a result of causes related to brain metastasis. CONCLUSION: Brain metastases were controlled well with radiosurgery alone as initial therapy. We advocate that WBRT should not be part of the initial treatment protocol for selected patients with one or two tumors with good control of their primary cancer, better Karnofsky Performance Scale score, and younger age, all of which are predictors of longer survival.     

CT引导下放射性~(125)I粒子组织间植入治疗肺癌

目的探讨CT引导下放射性125I粒子组织间植入治疗肺癌的技术可行性和近期疗效。方法2003年3月~2007年9月,对16例肺癌(12例肺转移癌,4例肺癌术后复发)行CT引导下放射性125I粒子植入治疗。局部麻醉。术前计算机治疗计划系统行三维治疗计划,确定粒子数目、空间分布和粒子针数目。既往放疗肿瘤匹配周边剂量为90~110Gy,未行放疗为140~160Gy。计划靶体积包括临床靶体积加1cm外周。每颗粒子活度为0.40~0.70mCi。中位植入粒子38颗(15~145颗),术后即刻行CT扫描进行质量验证。3例术后1周加三维适形放疗,总剂量45~50Gy。结果中位随访14个月(6~47个月)。无治疗相关严重并发症发生。1年和2年局部控制率分别为93.8%(15/16)和93.8%(15/16)。中位生存时间14个月(6~24个月),1年和2年生存率分别为62.5%(10/16)和37.5%(6/16)。6例死于全身转移,3例死于恶液质和1例死于脑出血。结论CT引导下放射性125I植入治疗复发或转移性肺癌安全,微创,并发症发生率低,疗效肯定,粒子治疗后配合外放疗和全身化疗,有望进一步提高疗效。     

Clinical application of a sustained release anticancer pellet

During a 6.5-year period from March 1978, 136 patients with brain tumors, which were diagnosed as gliomas or metastatic brain tumors during surgical operation, were treated by the application of sustained release anticancer pellets in seven institutes. Histological diagnosis disclosed that the majority of the tumors were malignant gliomas (61 cases), metastatic brain tumors (35 cases), and benign astrocytoma (17 cases). The anticancer agents (250 mg of 5FU, 1.5 mg of MMC, 250 mg of BUdR and 6,000 iu of urokinase) were sealed in a Silastic silicone tube of 6 mm in diameter, 0.25 mm in wall thickness, and 12 mm in length. The daily delivery of the drugs was (2-3)/10,000 of the original volume. This treatment was combined with surgical and irradiation therapy with or without general chemotherapy. The median survival time of patients with malignant gliomas was 545 days (18 months). The 1-year survival rate was 65.63%, and the 3-year survival rate 16.2%. On the other hand, in patients with benign astrocytomas, the median survival time was 1,500 days (4.1 years), 1-year survival rate 83.75%, and 3-year survival rate 42.84%. In those with metastatic brain tumors, the median survival time was 280 days, 1-year survival rate 43.87%, and 3-year survival rate 24.84%. The present findings revealed that the tube-type anticancer pellets cannot inhibit the growth of the brain tumors located 5 cm from the pellets.     

Stereotactic Radiosurgery for Human Glioma: Treatment Parameters and Outcome for Low vs. High Grade

Stereotactic radiosurgery (SRS) offers the precise, local delivery of radiation for the treatment of recurrent gliomas. We examined the comparative characteristics, treatments, and outcome in a population having with low– and high–grade gliomas. Between September 1991 and December 1995, 20 patients (13 males, 7 females) had SRS for low-grade [9 patients: World Health Organization (WHO) grade II] vs. high-grade (11 patients: 9 WHO grade IV and 2 WHO grade III) gliomas. The patients with low-grade gliomas were younger (mean age ± SE, 39.6 ± 5.4 years; range, 11.4–61.0 years) than those with high-grade gliomas (51.3 ± 13.9 years; range, 32.9–78.5 years) (P = 0.09). Tumor locations were similar in the two groups: lobar for 7 of 9 low-grade vs. 9 of 11 high-grade gliomas (P = NS) and diencephalic or cerebellar for the remainder. The initial surgical treatments were biopsy, subtotal resection, and total resection for three, three, and three patients with low-grade gliomas, vs. three, seven, and one patients with high-grade gliomas, respectively (P = NS). Except for three patients with low-grade gliomas, all patients had conventional postoperative fractionated external-beam radiotherapy. The doses were 5583 ± 342 vs. 5345 ± 261 cGy (P = NS) for low- vs. high-grade gliomas, respectively. Intervals from surgery and conventional radiation (if given) to progression and SRS tended to be longer for low-grade gliomas: 37.5 ± 9.5 vs. 30.6 ± 11.1 months (P = NS) for low- vs. high-grade gliomas, respectively. High-grade gliomas were larger. The diameters of the collimators that allowed enclosure of the enhancing tumor volume within the specified treatment isodoses were 22.4 ± 2.0 mm for low-grade vs. 29.8 ± 2.8 mm for high-grade gliomas (P = 0.02, ANOVA). SRS doses and isodose percentiles were similar, however, for the two groups: 1650 ± 191 cGy and 79 ± 4.0% vs. 1932 ± 182 cGy and75 ± 3.5% for low- vs. high-grade gliomas, respectively (P = NS, dose and isodose). All patients with high-grade gliomas were followed until death. The mean survival after SRS was 11.6 ± 1.5 months (42 ± 12 months after surgery). Five of nine patients with low-grade gliomas expired 31.6 ± 6.0 months after SRS (P < 0.001, Kaplan–Meier log rank) (74.0 ± 16.0 months after surgery). The four survivors have been followed for 8, 13, 35, and 38 months after SRS, respectively. Multivariate analysis shows that the category of histologic grade correlates significantly with survival after radiosurgery (P = 0.01). SRS may be an important therapeutic option for patients with recurrent gliomas, regardless of their grade.     

Stereotactic radiosurgery for the treatment of brain metastases: impact of cerebral disease burden on survival

Abstract Stereotactic radiosurgery (SRS) for brain metastases has been carried out at the Leeds Gamma Knife Centre since March 2009. The aim of this study was to examine the outcomes and toxicity in our initial cohort of patients. The medical records of patients with brain metastases referred to the Leeds Gamma Knife Centre between March 2009 and July 2010 were retrospectively reviewed. Data on survival, primary tumour, Karnofsky performance status, time from diagnosis to identification of brain metastases, previous treatment for brain metastases and results of staging prior to SRS were recorded. Patients were followed up with regular magnetic resonance imaging of the brain for a minimum of 6 months and data on toxicity and oral steroid dose were recorded. Statistical analysis was carried out using SPSS v14.0. Survival curves were compared using the Log Rank test. Fifty eight patients (19 male) had a median survival of 50.4 weeks (95% CI, 32.6-68.2 weeks). Lung (36%) and breast (27%) were the most common primary tumours. Patients with a total volume of metastases treated ?10?000 mm(3). In addition, largest treated lesion 相似文献   

Incidence of late radiation necrosis with transient mass effect after interstitial low dose rate radiotherapy for cerebral gliomas

Late radiation necroses constitute a hazard in low dose rate interstitial irradiation for inoperable gliomas. An incidence of 40% (8/20 patients) was found after permanent implantation of Iodine-125 seeds. This finding may even underestimate the real frequency, because follow-up of unaffected patients was shorter than in patients with radiation necrosis. The necrotic reactions caused a transient mass effect, which lead to a significant deterioration of performance scores. Further manifestations of late delayed radiation damage were observed in two patients. The occurrence of radiation necrosis was correlated with total radiation dose, amount of implanted radioactivity, and with velocity of tumour shrinkage. A mechanism underlying the development of radiation necrosis is proposed: A rapid shrinkage of tumour after interstitial Iodine-125 implantation may cause a significant irradiation of surrounding brain tissue, which was initially lying outside the target volume. Since most patients affected by radiation necrosis were children or adolescents, the risk of radiation damage should be minimized. This could probably be achieved either by reduction of irradiation dose, or by using temporary implants of Iodine-125.     

Adjuvant stereotactic radiosurgery for anaplastic ependymoma

OBJECT: The purpose of this retrospective study is to evaluate the role of stereotactic radiosurgery using the Gamma Knife as an adjuvant to other modalities used in the treatment of malignant ependymomas of both children and adults and to assess its efficacy in terms of tumor control and overall survival. METHOD: Between 1987 and 1998, 22 patients in the age range of 1.5-65 years (mean age 22. 3) with progressive anaplastic ependymoma were treated by stereotactic radiosurgery using the 201 source Co-60 Leksell Gamma Knife at the University of Pittsburgh. The irradiated tumor volume varied from 0.84 to 36.8 cm(3) (mean 13.7). The median dose delivered to the tumor margin was 16.1 Gy (range 10-20), and the mean maximal dose was 32.2 Gy (range 20-40). The disease-free survival, the tumor control rate and the overall survival were recorded to evaluate the efficacy of radiosurgery. The median follow-up from radiosurgery was 21 months (range 4-84). RESULTS: Median survival after radiosurgery was 2.2 years (46.6 +/- 12.1% 5-year actuarial). Median survival from the initial diagnosis was 10. 1 years (50.3 +/- 12.5% at 5 years, 37.7 +/- 14.4% at 10 years). Reduction or stabilization of the treated tumor was seen in 16 out of 22 (68%) patients. Forty-one percent of the patients eventually developed delayed distant cerebral recurrence outside the treated volume. The 5-year actuarial rates for local control and cranial control at any location were 62.3 +/- 13.6% and 32.4 +/- 10.8%, respectively. No complication occurred as a side effect of radiosurgery. CONCLUSION: For patients with locally recurrent or progressive anaplastic ependymomas, Gamma Knife stereotactic radiosurgery proved to be safe and effective as a salvage adjuvant therapy to achieve local tumor control and improve survival.     

Reoperation in the treatment of recurrent intracranial malignant gliomas

Fifty-five consecutive patients with recurrent intracranial malignant gliomas were reoperated at Memorial Sloan-Kettering Cancer Center from 1972 to 1983. The patients were 10 to 70 years old (median, 48 years). Thirty-five patients (64%) had glioblastoma multiforme, and 20 (36%) had anaplastic astrocytoma. The median interval between the first operation and reoperation was 43 weeks. The Karnofsky rating before reoperation ranged from 40 to 90 (median, 70). Eleven patients (20%) had more than one reoperation. The mortality rate was 1.4% per procedure, and the morbidity rate was 16% per procedure. After reoperation, 41 patients (75%) had chemotherapy and/or radiation therapy. The median survival for all patients was 92 weeks. The median survival after reoperation was 36 weeks. Patients with Karnofsky ratings of greater than or equal to 70, with anaplastic astrocytomas, or in whom gross total removal of the tumor was undertaken lived longer than their respective counterparts (P less than 0.05). Prereoperation Karnofsky rating and extent of surgical resection were the most important independent factors related to survival after reoperation according to multivariate analysis (P less than 0.01 and P less than 0.05, respectively). Twenty-five patients (45%) had improved Karnofsky ratings after reoperation, and the 32 patients (58%) who were independent after reoperation were able to stay so for more than 6 months of their survival time (median value). Reoperation is feasible and can be accomplished with acceptable mortality and morbidity. When intracranial malignant gliomas recur, the combined use of reoperation and adjuvant therapy prolongs good quality life.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hemangiopericytoma in the central nervous system: treatment,pathological features,and long-term follow up in 38 patients

OBJECT: The authors reviewed the Mayo Clinic experience with the treatment of hemangiopericytoma in the primary central nervous system (CNS). METHODS: A retrospective study of all patients at the Mayo Clinic revealed 38 who had been treated for hemangiopericytoma in the CNS. Twenty of these patients were diagnosed in the decade between 1990 and 2000; 18 were initially diagnosed and underwent surgery before 1990. In the patients treated since 1990, the 5-year Kaplan-Meier survival rate was 93%. The 5-year disease-free survival rate was 89%. Sixty percent of patients treated with the aid of stereotactic radiosurgery for recurrent disease were alive 4.4 years after their initial treatment. Salvage chemotherapy was not effective. No survival benefit was detected inpatients who had received initial adjuvant external-beam radiation therapy. High-grade tumors recurred 6.7 years earlier than did low-grade lesions (p = 0.004). CONCLUSIONS: The 5-year survival rate in patients with hemangiopericytoma of the CNS has improved at the authors' institution during the last 10 years. Although the reason for this is not entirely clear, the authors suspect that the improved treatment of patients with cancer, a 0% intraoperative mortality rate, and the use of radiosurgery in the treatment of recurrent disease all likely contribute. High-grade tumors recurred statistically significantly earlier than low-grade lesions. Current chemotherapies are ineffective in the treatment of hemangiopericytoma of the CNS.     

Stereotactic radiosurgery in the treatment of metastatic disease to the brain

OBJECTIVE: In recent years, stereotactic radiosurgery has been growing in popularity as a treatment modality for metastatic disease to the brain. The technique has advantages of reduced cost and low morbidity compared with open surgical treatment. Furthermore, it avoids the potential cognitive side effects of fractionated whole-brain radiotherapy. We undertook this study to determine the usefulness of adjuvant radiation therapy and to determine prognostic factors in patients treated with stereotactic radiosurgery. METHODS: We reviewed our series of patients with metastatic tumors treated using gamma knife stereotactic radiosurgery from August 1994 to February 1999. Nonparametric methods were used to compare treatment subgroups by demographic features including age, Karnofsky Performance Scale score, diagnosis, and systemic disease status. Univariate and multivariate analyses of survival and freedom from progression were performed using Kaplan-Meier and Cox proportional hazards regression techniques. RESULTS: This study included 190 patients harboring 431 lesions who were treated in 263 treatment sessions. The median follow-up after radiosurgery was 36 weeks for all patients. The median actuarial survival from the time of radiosurgery in all patients was 34 weeks. When patients were stratified according to tumor histology, those without melanoma had a median survival of 39 weeks, and those with melanoma had a median survival of 28 weeks. The cause of death could be determined in 122 (92%) of the patients known to have died during the data capture period. For patients harboring melanoma, death was attributable to systemic disease in 31 (47%), to central nervous system-related processes in 29 (44%), and to unknown causes in 6 (9%). For non-melanoma patients, death was attributable to systemic disease in 45 (68%), to central nervous system-related processes in 17 (26%), and to unknown causes in 4 (6%). Significantly improved survival (P = 0.002) was observed in patients with controlled systemic disease. No significant difference in survival could be ascertained for patients presenting with up to four lesions, although patients with a total tumor volume greater than 9 cc had shortened survival. No survival benefit could be demonstrated for whole-brain radiotherapy administered either concomitantly or after radiosurgery. CONCLUSION: Factors correlated with significantly improved survival included controlled systemic disease and non-melanoma histology. We found no significant survival benefit that could be discerned from adjuvant whole-brain radiotherapy in this patient group.     

LINAC Radiosurgery for Patients with a Limited Number of Brain Metastases

Patients (pts) with brain metastases have a high risk of cancer-related death due to extra- or intracranial tumor manifestations. The present retrospective analysis demonstrates the ability of linear accelerator (LINAC)-based radiosurgery to control intracranial disease and prolong survival in pts with one to three metastases. From 1991 to 1996, 106 pts (42 females, 64 males; median age, 57 years) with cerebral metastases were treated by stereotactic radiosurgery with a LINAC (8 MeV) equipped with tertiary collimators. In 70 pts, a single metastasis was present; 36 pts had two or three metastases. Fifty-nine pts were treated for their first occurrence of brain metastases; 47 pts had been treated prior to radiosurgery by resection and/or whole-brain irradiation. Histology of the primary tumor was non–small cell lung cancer (36 pts), melanoma (20 pts), breast cancer (15 pts), hypernephroma (15 pts), and other (20 pts). All together, 157 metastases (0.04–69.0 ml; median, 2.7 ml) were irradiated with marginal doses of 12–25 Gy (median, 20 Gy) referred to the 65–80% isodose. Seventy-two percent of the lesions were treated with a single isocenter. Adjuvant whole-brain irradiation was applied in six pts. One hundred thirty-five of 157 metastases were evaluated for response: complete response (CR), 24%; partial response, 31%; no change, 30%; and progression of disease, 15%. CR rates were highest (48%) in small metastases (<1-cm diameter), independent of histological type and dose. The overall median survival was 8 months. Multivariate Cox regression analysis revealed a significant impact on survival for Karnofsky performance score, presence of extracranial tumor, and volume of largest metastasis. Freedom from neurological death was determined only by the volume of the largest metastasis. Patients with multiple metastases and/or extracranial disease had a higher risk of developing new outfield brain metastases. Due to salvage therapy (second or third course of stereotactic radiosurgery, whole-brain irradiation, surgery), the overall survival in pts with two or three metastases did not significantly differ from that in pts with single metastases. LINAC-based stereotactic radiosurgery in pts with up to three cerebral metastases results in survival rates approaching those of pts with resected single brain metastases. As pts with both single and multiple metastases can effectively be salvaged after receiving radiosurgery, extracranial tumor activity becomes a major determinator of survival.