Gamma-knife radiosurgery for brain metastases of renal cell carcinoma: results in 23 patients

Stereotactic Ablative Radiation (SAbR) for Oligometastatic RCC

A significant proportion of metastatic renal cell carcinoma (mRCC) patients present with oligometastatic disease. Retrospective and limited prospective data suggests that a subgroup of patients with oligometastatic mRCC benefits from aggressive local therapy. With the emerging data of high local control efficacy with low toxicity of stereotactic ablative radiation (SAbR) for both CNS and extra-cranial mRCC, SAbR may play a critical role in the multi-modality management of mRCC patients with oligometastatic disease. In addition to local control benefit, the benefit of SAbR in this patient population can range from longitudinal disease control, maintaining quality of life, deferring systemic therapy, immune-modulation and even improving survival. A review of the retrospective data suggests that SAbR benefits oligometastatic mRCC patients with metachronous metastases, and perhaps those with indolent biology. Large prospective trials are indicated to successfully integrate SAbR of oligometastatic mRCC with the available systemic therapies to harness the optimal benefit of SAbR for this patient population.

Radiotherapy and Renal Cell Carcinoma: A Continuing Saga

Renal cell carcinoma (RCC) is one of the most aggressive malignancies of the genito-urinary tract, having a poor prognosis especially in patients with metastasis. Surgical resection remains the gold standard for localized renal cancer disease, with radiotherapy (RT) receiving much skepticism during the last decades. However, many studies have evaluated the role of RT, and although renal cancer is traditionally considered radio-resistant, technological advances in the RT field with regards to modern linear accelerators, as well as advanced RT techniques have resulted in breakthrough therapeutic outcomes. Additionally, the combination of RT with immune checkpoint inhibitors and targeted agents may maximize the clinical benefit. This review article focuses on the role of RT in the therapeutic management of renal cell carcinoma.

Radiation Therapy for Patients with Advanced Renal Cell Carcinoma

Stereotactic radiosurgery and stereotactic body radiation therapy (SBRT) have led to a resurgence of the use of radiotherapy in the management of advanced renal cell carcinoma (RCC). These techniques provide excellent local control and palliation of metastatic sites of disease with minimal toxicity. Additionally, SBRT to the primary tumor may be efficacious and well tolerated in select patients that are not surgical candidates. Emerging data suggest that SBRT may potentiate the immune response, and current and future study will evaluate if SBRT can improve survival outcomes in patients with metastatic RCC.

Radiotherapy for renal cell carcinoma: renaissance of an overlooked approach

Conventional radiotherapy previously had a limited role in the definitive treatment of renal cell carcinoma (RCC), owing to the disappointing outcomes of several trials and the perceived radioresistance of this type of cancer. In this context, radiotherapy has been relegated largely to the palliation of symptoms in patients with metastatic disease, with variable rates of response. Following the availability of newer technologies that enable safe delivery of high-dose radiotherapy, stereotactic ablative radiotherapy (SABR) has become increasingly used in patients with RCC. Preclinical evidence demonstrates that RCC cells are sensitive to ablative doses of radiotherapy (≥8-10 Gy). Trials in the setting of intracranial and extracranial oligometastases, as well as primary RCC, have demonstrated excellent tumour control using this approach. Additionally, an awareness of the capacity of high-dose radiation to stimulate antitumour immunity has resulted in novel combinations of SABR with immunotherapies. Here we describe the historical application of conventional radiotherapy, the current biological understanding of the effects of radiation, and the clinical evidence supporting the use of ablative radiotherapy in RCC. We also explore emerging opportunities to combine systemic targeted agents or immunotherapies with radiation. Radiotherapy, although once an overlooked approach, is moving towards the forefront of RCC treatment.

Stereotactic Radiosurgery for Renal Cancer Brain Metastasis: Prognostic Factors and the Role of Whole-Brain Radiation and Surgical Resection

Background. Renal cell carcinoma is a frequent source of brain metastasis. We present our consecutive series of patients treated with Stereotactic Radiosurgery (SRS) and analyse prognostic factors and the interplay of WBRT and surgical resection. Methods. This is a retrospective study of 66 patients with 207 lesions treated with the Cyberknife radiosurgery system in our institution. The patients were followed up with imaging and clinical examination 1 month and 2-3 months thereafter for the brain metastasis. Patient, treatment, and outcomes characteristics were analysed. Results. 51 male (77.3%) and 15 female (22.7%) patients, with a mean age of 58.9 years (range of 31–85 years) and a median Karnofsky Performance Status (KPS) of 90 (range of 60–100), were included in the study. The overall survival was 13.9 months, 21.9 months, and 5.9 months for the patients treated with SRS only, additional surgery, and WBRT, respectively. The actuarial 1-year Local Control rates were 84%, 94%, and 88% for SRS only, for surgery and SRS, and for WBRT and additional SRS, respectively. Conclusions. Stereotactic radiosurgery is a safe and effective treatment option in patients with brain metastases from RCC. In case of a limited number of brain metastases, surgery and SRS might be appropriate.

Safety and efficacy of outpatient gamma knife radiosurgery for multiple cerebral metastases

This review highlights the experience of a single institution using the Leksell gamma knife for 8 years. More than 500 patients with multiple cerebral metastases received outpatient radiosurgery. The results prove that there is a high efficacy and attractively low morbidity of modern outpatient radiosurgery. When compared with whole brain radiation therapy, radiosurgery improved survival in patients with cerebral metastases. Most importantly, the number of brain metastases had no prognostic impact in patients with non-small cell lung cancer, renal cell cancer, malignant melanoma and gastrointestinal cancer.

Stereotactic radiosurgery with and without whole-brain radiotherapy for newly diagnosed brain metastases

Brain metastases develop in 20-40% of cancer patients and can cause significant morbidity. In selected patients with one to three lesions, stereotactic radiosurgery may be used to improve local control. However, it is unclear whether whole-brain radiotherapy is necessary for all patients who are candidates for stereotactic radiosurgery. While whole-brain radiotherapy may improve the locoregional control of brain metastases, it may cause long-term side effects and may not improve overall survival in some patients. Its benefits should be evaluated in the context of risks of neurocognitive deterioration, either from whole-brain radiotherapy or from uncontrolled brain metastases, and the possible need for salvage treatments with the omission of initial whole-brain radiotherapy. For certain radioresistant brain metastases, the benefit of whole-brain radiotherapy to patients who have stereotactic radiosurgery is uncertain.

Stereotactic radiosurgery for the treatment of melanoma and renal cell carcinoma brain metastases

Renal cell carcinoma (RCC) and melanoma brain metastases have traditionally been considered radioresistant lesions when treated with conventional radiotherapeutic modalities. Radiosurgery provides high-dose radiation to a defined target volume with steep fall off in dose at lesion margins. Recent evidence suggests that stereotactic radiosurgery (SRS) is effective in improving local control and overall survival for a number of tumor subtypes including RCC and melanoma brain metastases. The purpose of this study was to compare the response rate to SRS between RCC and melanoma patients and to identify predictors of response to SRS for these 2 specific subtypes of brain metastases. We retrospectively reviewed a prospectively maintained database of all brain metastases treated with Gamma Knife SRS at the University Health Network (Toronto, Ontario) between October 2007 and June 2010, studying RCC and melanoma patients. Demographics, treatment history and dosimetry data were collected; and MRIs were reviewed for treatment response. Log rank, Cox proportional hazard ratio and Kaplan-Meier survival analysis using SPSS were performed. A total of 103 brain metastases patients (41 RCC; 62 melanoma) were included in the study. The median age, Karnofsky performance status score and Eastern Cooperative Oncology Group performance score was 52 years (range 27-81), 90 (range 70-100) and 1 (range 0-2), respectively. Thirty-four lesions received adjuvant chemotherapy and 56 received pre-SRS whole brain radiation therapy. The median follow-up, prescription dose, Radiation Therapy Oncology Group conformity index, target volume and number of shots was 6 months (range 1-41 months), 21 Gy (range 15-25 Gy), 1.93 (range 1.04-9.76), 0.4 cm3 (range 0.005-13.36 cm3) and 2 (range 1-22), respectively. Smaller tumor volume (P=0.007) and RCC pathology (P=0.04) were found to be positive predictors of response. Actuarial local control rate for RCC and melanoma combined was 89% at 6 months, 84% at 12 months, 76% at 18 months and 61% at 24 months. Local control at 12 months was 91 and 75% for RCC and melanoma, respectively. SRS is a valuable treatment option for local control of RCC and melanoma brain metastases. Smaller tumor volume and RCC pathology, predictors of response, suggest distinct differences in tumor biology and the extent of radioresponse between RCC and melanoma.

Outcome predictors of gamma knife radiosurgery for renal cell carcinoma metastases

BACKGROUND

Although whole-brain radiation therapy (WBRT) has been a standard palliative management for brain metastases from renal cell carcinoma, its benefit has been elusive because of radiobiological resistance.

OBJECTIVE

To evaluate the role of stereotactic radiosurgery (SRS) in the management of brain metastases from renal cell carcinoma.

METHODS

We reviewed records from 158 consecutive patients (men = 111, women = 47) who underwent SRS for 531 brain metastases from renal cell carcinoma. The median patient age was 61 years (range, 38-83 years), and the median number of tumors per patient was 1 (range, 1-10). Seventy-nine patients (50%) had solitary brain metastasis. Fifty-seven patients (36%) underwent prior WBRT. The median total tumor volume for each patient was 3.0 cm3 (range, 0.09-47 cm).

RESULTS

The overall survival after SRS was 60%, 38%, and 19% at 6, 12, and 24 months, respectively, with a median survival of 8.2 months. Factors associated with longer survival included younger age, longer interval between primary diagnosis and brain metastases, lower recursive partitioning analysis class, higher Karnofsky performance status, smaller number of brain metastases, and no prior WBRT. Median survival for patients with < 2 brain metastases, higher Karnofsky performance status (> 90), and no prior WBRT was 12 months after SRS. Sustained local tumor control was achieved in 92% of patients. Symptomatic adverse radiation effects occurred in 7%. Overall, 70% of patients improved or remained neurologically stable.

CONCLUSION

Stereotactic radiosurgery is an especially valuable option for patients with higher Karnofsky performance status and smaller number of brain metastases from renal cell carcinoma.

Treatment strategy for metastatic brain tumors from renal cell carcinoma: selection of gamma knife surgery or craniotomy for control of growth and peritumoral edema

We retrospectively studied the efficacy of gamma knife surgery (GKS) for metastatic brain tumors from renal cell carcinoma (RCC). To evaluate the efficacy of GKS for control of peritumoral edema, we retrospectively studied 280 consecutive metastatic brain tumors (100 from lung cancers, 100 from breast cancers, and 80 from RCC) associated with peritumoral edema. In addition, this study included 11 patients with metastatic brain tumors from RCC who underwent direct surgery. The tumor growth control rate of GKS was 84.3%. The extent of edema of RCC metastases was significantly larger than those from lung and breast cancer. Primary site (renal or not renal) and delivered marginal dose (25 Gy or more) were significantly correlated with control of peritumoral edema. All tumors treated by direct surgery were more than 2 cm in maximum diameter. Peritumoral edema at surgery was extensive but disappeared within 1-3 months, and neurological symptoms also improved in many cases. Total removal of brain metastases from RCC was easy with little bleeding in most cases. Our results suggest that GKS is effective for growth control of metastatic brain tumors from RCC. Higher marginal dose such as 25 Gy or more is desirable to obtain peritumoral edema control, so GKS is not suitable for control of symptomatic peritumoral edema associated with relatively large tumors. Tumor removal of RCC metastases is relatively easy and rapidly reduces peritumoral edema. Treatment strategy for metastatic brain tumors from RCC depends on tumor size, number of tumors, and presence of symptomatic peritumoral edema.

Multidisciplinary treatment of brain metastases derived from clear cell renal cancer incorporating stereotactic radiosurgery

BACKGROUND

Brain metastases are a frequent complication in patients with metastatic clear cell renal cancer. Survival after whole-brain radiotherapy (WBRT) is disappointing. A retrospective analysis of multimodality treatment was performed in patients who had received linear accelerator (LINAC)-based stereotactic radiosurgery (SRS).

METHODS

Thirty-two patients underwent SRS-based treatment for 71 metastatic foci between 2000 and 2006. All patients had a Karnofsky performance status >or=70 and all 32 patients had extracranial metastatic disease (Radiation Therapy Oncology Group recursive partitioning analysis [RPA] Class 2). Survival was calculated from the time of diagnosis of brain metastases. The minimum potential follow-up was 1 year after SRS. Univariate and multivariate analysis of potential prognostic factors affecting survival was performed.

RESULTS

Twenty-six patients required only 1 SRS treatment (84%) to achieve central nervous system (CNS) control, whereas 5 patients received 2 to 3 treatments (16%). The median survival of renal cancer patients from the diagnosis of brain metastases was 10.1 months (95% confidence interval, 6.4-14.8 months). One-year and 3-year survival rates were 43% and 16%, respectively. The addition of surgery or WBRT did not appear to prolong survival. Immunotherapy after control of brain metastases with SRS appeared to result in significantly improved survival. Survival was also found to be strongly influenced by prognostic stratification of metastatic disease using Motzer or modified risk criteria.

CONCLUSIONS

The results of the current study demonstrated that SRS-based treatment of patients with up to 5 brain metastases from clear cell renal cancer is feasible and results in excellent CNS control. Survival beyond 3 years from the time of diagnosis of brain metastases was achievable in 16% of patients and was associated with the use of systemic immunotherapy with interleukin-2 and interferon but not antiangiogenic agents.

Immunohistochemical markers to distinguish between hemangioblastoma and metastatic clear-cell renal cell carcinoma in the brain: utility of aquaporin1 combined with cytokeratin AE1/AE3 immunostaining

Distinguishing hemangioblastomas from metastatic clear-cell renal cell carcinomas (CCRCCs) in the brain is a diagnostic challenge owing to similar clinical and morphologic presentations. Inhibin-alpha and aquaporin1 were shown as positive markers of hemangioblastoma, but are not totally reliable distinguishing hemangioblastoma from metastatic CCRCC. This study shows that the diagnosis can be achieved using a combination of markers. To identify the panel of markers useful for this differential, 67 hemangioblastomas and 34 metastatic CCRCCs were analyzed using a panel of antibodies including aquaporin1, inhibin-alpha, D2-40, cytokeratin AE1/AE3, epithelial membrane antigen, and CD10. The study confirms the usefulness of aquaporin1 (97% sensitivity, 83% specificity) and inhibin-alpha (88% sensitivity, 79% specificity) as positive markers of hemangioblastoma and shows that aquaporin1 is a superior positive marker versus inhibin-alpha for the differential. Positivity of tumor cells with cytokeratin AE1/AE3 is the signature of a metastatic CCRCC (100% specificity, 88% sensitivity) and CD10 expression as well (100% specificity, 79% sensitivity). The combined use of aquaporin1 and AE1/AE3 yields a high degree of sensitivity and specificity to differentiate between hemangioblastoma and metastatic CCRCC. All tumors but one aquaporin1 positive and cytokeratin AE1/AE3 negative (65/66) correspond to hemangioblastomas (97% sensitivity, 97% specificity, 98.5% diagnostic positive predictive value). Tumors with the opposite profile, aquaporin1 negative, and cytokeratin AE1/AE3 positive, (25/25), correspond to metastatic CCRCC (74% sensitivity, 100% specificity, 100% diagnostic positive predictive value). In summary, aquaporin1 is the most sensitive positive marker of hemangioblastoma. Despite its moderate specificity, when used in combination with epithelial marker AE1/AE3, it allowed to reliably distinguish hemangioblastoma from metastatic CCRCC.

New immunohistochemical markers in the evaluation of central nervous system tumors: a review of 7 selected adult and pediatric brain tumors

CONTEXT

Immunohistochemistry (IHC) has become an important tool in the diagnosis of brain tumors.

OBJECTIVE

To review the latest advances in IHC in the diagnostic neuro-oncologic pathology.

DATA SOURCES

Original research and review articles and the authors' personal experiences.

DATA SYNTHESIS

We review the features of new, useful or potentially applicable marker antibodies as well as the new uses of already established antibodies in the area of diagnostic neuro-oncologic pathology, focusing on the use of IHC for differential diagnosis and prognosis. We discuss (1) placental alkaline phosphatase, c-Kit, and OCT4 for germinoma, (2) alpha-inhibin and D2-40 for capillary hemangioblastoma, (3) phosphohistone-H3 (PHH3), MIB-1/Ki-67, and claudin-1 for meningioma, (4) PHH3, MIB-1/Ki-67, and p53 for astrocytoma, (5) synaptophysin, microtubule-associated protein 2, neurofilament protein, and neuronal nuclei for medulloblastoma, (6) INI1 for atypical teratoid/rhabdoid tumor, and (7) epithelial membrane antigen for ependymoma. All the markers presented here are used mainly for supporting or confirming the diagnosis, with the exception of the proliferation markers (MIB-1/Ki-67 and PHH3), which are primarily used to support grading and are reportedly associated with prognosis in certain categories of brain tumors.

CONCLUSIONS

Although conventional hematoxylin-eosin staining is the mainstay for pathologic diagnosis, IHC has played a major role in differential diagnosis and in improving diagnostic accuracy not only in general surgical pathology but also in neuro-oncologic pathology. The judicious use of a panel of selected immunostains is unquestionably helpful in diagnostically challenging cases. In addition, IHC is also of great help in predicting the prognosis for certain brain tumors.

Gamma Knife surgery for metastatic brain tumors from renal cell carcinoma

Object

The authors evaluated the results of Gamma Knife surgery (GKS) for the treatment of metastatic brain tumors from renal cell carcinoma (RCC).

Methods

The authors conducted a retrospective review of the clinical characteristics and treatment outcomes in 69 patients with metastatic brain tumors from RCC who underwent GKS at the authors’ institution. Fifty-one patients were men, and 18 were women. The mean patient age was 64.2 years (range 45–85 years).

The 69 patients underwent a total of 104 GKS procedures for treatment of 314 tumors. Eighteen patients received repeated GKS. Follow-up magnetic resonance (MR) imaging was used at a mean of 7.1 months after GKS to evaluate the change in 132 tumors after treatment. The mean prescription dose at the tumor margin was 21.8 Gy. The tumor growth control rate was 82.6%. Tumor volume and the delivered peripheral dose were significantly correlated with tumor growth control on univariate and multivariate analyses. Sixty (45.5%) of the 132 tumors assessed with MR imaging were associated with apparent peritumoral edema at the time of GKS. After treatment, peritumoral edema disappeared in 27 tumors, decreased in 13, was unchanged in 16, and progressed in four. Newly developed peritumoral edema after GKS was rare. The delivered peripheral dose was significantly correlated with control of peritumoral edema. The overall median survival time after GKS was 9.5 months. In this study, 34 patients died of systemic disease and 10 died of progressive brain metastases. Multivariate analysis showed that the number of lesions at the first GKS, the Karnofsky Performance Scale score at the first GKS, the recursive partitioning analysis classification, and the interval from diagnosis of RCC to brain metastasis were significantly correlated with survival time.

Conclusions

Gamma Knife surgery is effective for metastatic brain tumors from RCC. The disappearance rate of tumors is relatively low, but growth control is high. The delivered dose to the tumor margin is significantly correlated with the control of peritumoral edema. Gamma Knife surgery should be used as the initial treatment modality, if possible, even in patients with multiple metastases. Repeated GKS is recommended for newly developed brain metastases because of the low sensitivity of RCC to conventional radiation therapy.

LINAC Radiosurgery as Single Treatment in Cerebral Metastases

OBJECTIVE

Stereotactic radiosurgery is a radiation technique of high radiation dose focused on a stereotactic intracranial target in a single fraction with high precision. LINAC Radiosurgery has gained increasing relevance in the treatment of brain metastases since it was introduced by Sturm (1987). METHOD AND PATIENT SELECTION: From January 1996 to August 2003 110 patients were treated with LINAC Radiosurgery. A combination of the University of Florida system and the X Knife System developed by Radionics was used in all patients. Seventy patients had a single and 40 patients multiple metastatic lesions at the time of diagnosis and treatment. Overall 161 intracerebral metastases were treated. Median tumor volume was 3.1 ccm (0.3-15 ccm). Median radiation dose to the tumor margin was 1830 cGy (range 1100-2200 cGy) prescribed to the 80% isodose line. Whole brain radiation therapy with a total dose of 30 Gy in 10 fractions was performed in 35 patients because of multiple metastases and LINAC Radiosurgery was used as boost for recurrences. In 75 patients LINAC Radiosurgery was used as single treatment.

RESULTS

The follow-up period was between 6 and 72 months. Local tumor control rate was 89.4%. Seventeen out of 161 metastases treated showed local recurrence. Eleven out of 75 patients treated with radiosurgery as single treatment developed distant recurrence and 3 out of 35 patients who were treated with whole brain radiation therapy (WBRT) and radiosurgery as boost. The 1-year survival rate is 54.9% with a median survival of 54 weeks.

CONCLUSION

LINAC Radiosurgery is an effective and safe treatment modality in patients with cerebral metastases located in any area of the brain. WBRT should be preserved for patients with multiple metastases or be delayed until multiple recurrence occurs. Surgery is still the treatment of choice in metastases with mass effect and surgical accessible location.

[Local relapse and single site of metastatic involvement of renal tumour. Prognostic factors and survival]

OBJECTIVE

To evaluate the clinical and pathological characteristics and survival in patients surgically treated for renal tumours that had local recurrence or metastasis to a single site.

MATERIAL AND METHODS

A retrospective study of 321 nephrectomies, evaluating the clinical and pathological variables in patients having local recurrence or metastasis to a single site, and who were treated surgically. Study and comparison of survival in the different groups.

RESULTS

The only factor found to have an independent influence on local recurrence is pathological stage. Local recurrence and the presence of metastasis to a single site have similar survival rates, both being statistically worse than in patients without metastasis at diagnosis, but better than in those having metastasis at diagnosis.

CONCLUSIONS

The presence of local recurrence has the same prognosis as a single excisable metastatic site, the prognosis being better than those initially with metastasis subjected to nephrectomy before receiving systemic treatment.

Treatment of brain metastases in renal cell carcinoma: radiotherapy, radiosurgery, or surgery?

Metastases from renal cell carcinoma raise specific therapeutic problems because they are relatively unresponsive to whole brain radiation therapy and tend to bleed. Recently, stereotactically guided high-precision irradiation as a single dose application (radiosurgery) showed promising treatment results for selected patients with brain metastases from renal cell carcinoma. Radiosurgery appears attractive due to its low risk and minimal invasiveness. Multiple lesions can be treated at the same time and retreatments can be performed for local or distant recurrences.

Practice and progress in kidney cancer: methodology for novel drug development

PURPOSE

The minimal efficacy of standard therapy for metastatic renal cell carcinoma (RCC) has resulted in the evaluation of numerous novel agents. Some agents have shown promise in phase II trials and yet none have improved survival over standard therapy in phase III trials. We examined existing data relevant to standard therapy and clinical trial methodology in RCC to understand patient, disease and trial design factors that have impacted clinical trial outcome and drug evaluation. Furthermore, we describe new paradigms for the evaluation of novel agents to optimize the yield of clinical research in RCC.

MATERIALS AND METHODS

A comprehensive review of published retrospective analyses and phase II/phase III trials in patients with metastatic RCC was undertaken. Publications with patient selection and/or therapeutic implications in our judgment are presented and evaluated.

RESULTS

Patients with good performance status and access to centers with experienced staff may appropriately receive high dose interleukin-2 after consideration of the relative risks and benefits. Alternatively low dose, single agent cytokine regimens are acceptable. Novel agents may be tested in untreated and refractory RCC. Consideration of the prognostic factors of a given phase II cohort is essential when interpreting single arm clinical trial results. RCC histological subtypes continue to be distinguished biologically and treatment relevant to the vascular endothelial growth factor pathway is most appropriately targeted to clear cell RCC. Nephrectomy in metastatic RCC may impact evaluation of the tumor response and survival in metastatic RCC. Thus, consideration of nephrectomy status in phase II trials and stratification in phase III trials is warranted. Clinical trials that include patients with central nervous system metastases should have standardized treatment of these metastases prior to systemic therapy. Objective response rate as an end point should be used with caution, given its unreliable history in metastatic RCC. Novel trial designs using time to disease progression may allow for interpretation of the antitumor effect in the absence of tumor shrinkage.

CONCLUSIONS

Metastatic renal carcinoma is a model disease for the design of clinical trials and testing of novel agents. Novel trial designs and end points should be considered to evaluate new agents in RCC. Phase III trials must be carefully performed with the most promising agents to impact survival in this disease.

LINAC radiosurgery for brain metastasis of renal cell carcinoma

The purpose of the study was to evaluate the efficacy and toxicity of stereotactic radiotherapy in the treatment of the brain metastasis of renal cell carcinoma. From 1994 to 2001, 28 patients presenting with 65 metastases of renal cell cancer were treated by radiosurgery. Median age was 55 years (35-75), and median Karnofski performance status ranges between 50 and 100. Seven patients had received whole brain radiotherapy (WBRT) before radiosurgery. Twelve patients were treated by radiosurgery for 1 metastasis, 5 patients for two metastases and 6 for three, and 5 for more than three metastases. One procedure was performed in 22 patients and, 2 or 3 procedures for 6 patients. Median metastasis diameter was 19 mm (5-55 mm). Median metastasis volume was 1.28 cc (0.02-28 cc). Irradiation was delivered by linear accelerator. Median minimal dose (on the 70% isodose) was 14.7 Gy (10.8 Gy, 19.5 Gy), median maximal dose (at the isocenter) 20.5 Gy (14.3 Gy, 39.6 Gy). Median follow-up was 14 months (1-33). Two metastases progressed (3%), 2 and 12 months after radiosurgery. Overall, crude local control rate was 97% and 3-, 6- and 12-month local control rates were 98% +/- 2%, 98% +/- 2%, and 93% +/- 5%, respectively. In univariate analysis, no prognostic factor of local control was retrieved. Median brain disease-free survival was 25 months after RS. the 3-, 6- and 12-month distant brain control rates were 91% +/- 4%, 91% +/- 4%, and 70% +/- 12%, respectively. Median survival duration was 11 months. The 3-, 6-, 12- and 24-month overall survival rates were 82% +/- 7%, 67% +/- 9%, 48% +/- 10%, and 33% +/- 10%, respectively. According to univariate analysis, only site of metastasis was overall survival prognostic factor. Radiosurgery for brain metastasis of renal cell carcinoma is an effective and accurate treatment. The use of radiosurgery alone is an appropriate management strategy for many patients with brain metastasis of renal cell carcinoma. Radiosurgery is efficient even after development of new metastasis appearing after WBRT.

Results of whole brain radiotherapy and recursive partitioning analysis in patients with brain metastases from renal cell carcinoma: a retrospective study

PURPOSE

To determine the benefit of whole brain radiotherapy (WBRT) and the use of the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) classification system in patients with brain metastases from renal cell carcinoma.

METHODS AND MATERIALS

We identified 46 consecutive patients with brain metastases from renal cell carcinoma who were treated with WBRT at the Cleveland Clinic Foundation between 1983 and 2000. We reviewed their charts for patient and tumor characteristics and categorized them according to the RTOG RPA classes.

RESULTS

The median follow-up and survival time for all 46 patients (15 women and 31 men) was 3.0 months. The median radiation dose was 3000 cGy in 10 fractions. Patients who received higher radiation doses (>3000 cGy) survived longer than those who received 3000 cGy or less than 3000 cGy (8.5 months vs. 2.7 months vs. 0.4 months, p = 0.0289). However, the Karnofsky performance status and RPA class were confounding factors in these data. The median survival for patients by RTOG RPA class was 8.5 months for Class I (n = 2), 3 months for Class II (n = 37), and 0.6 months for Class III (n = 7, p = 0.0834).

CONCLUSION

Despite the relatively poor prognosis of patients who receive WBRT alone, it appears that they benefit from this palliative treatment. The RTOG RPA classification system may be a useful tool in assessing prognosis in this patient population.

The role of gamma knife radiosurgery in the treatment of primary and metastatic brain tumors

With the widespread diffusion of stereotactic radiosurgical procedures, GKR treatments have gained considerable momentum as a major therapeutic option for patients harboring primary or metastatic brain tumors. Present results in high grade gliomas indicate a potential palliative role of this technique. The overall low radiosensitivity of these oncotypes and their infiltrative nature-with the resulting problems in properly defining the tumor target-are still a major obstacle to further development of the approach. In this regard, useful contributions are expected from advances in molecular neurobiology and functional neuroimaging as shown by preliminary investigations with MR spectroscopy. Surgery maintains a dominant role in the therapeutic armamentarium for low grade gliomas. However, in unfavorable cases (unresectable tumors, recurrences), GKR seems to be an effective alternative to conventional radiochemotherapy. In grade 2 astrocytomas and specifically in grade 1 pilocytic forms, short-to-mid-term reported studies have documented encouraging 70 to 93% local tumor control rates, with minimal cerebral toxicity. Finally, during the last decade, GKR has become a primary treatment choice for patients harboring small-to-medium-size brain metastases, with reasonable life expectancy and no impending intracranial hypertension. Focal tumor responses are consistently elevated, even in the most radioresistant oncotypes (melanoma, renal carcinoma); median and actuarial survival rates are far better than with conventional radiation treatments and are comparable to those observed in accurately selected surgical-radiation series.

Neurologic complications of solid tumors

This article reviews the neurologic complications of the most common solid tumors, including lung, breast, gastrointestinal, genitourinary, gynecologic, head and neck cancers, melanoma and sarcomas. As systemic therapy improves for many of these tumors, patients are surviving longer and the incidence of neurologic complications is increasing.

Radiosurgery in patients with renal cell carcinoma metastasis to the brain: long-term outcomes and prognostic factors influencing survival and local tumor control

OBJECT

Renal cell carcinoma is a leading cause of death from cancer and its incidence is increasing. In many patients with renal cell cancer, metastasis to the brain develops at some time during the course of the disease. Corticosteroid therapy, radiotherapy, and resection have been the mainstays of treatment. Nonetheless, the median survival in patients with renal cell carcinoma metastasis is approximately 3 to 6 months. In this study the authors examined the efficacy of gamma knife surgery in treating renal cell carcinoma metastases to the brain and evaluated factors affecting long-term survival.

METHODS

The authors conducted a retrospective review of 69 patients undergoing stereotactic radiosurgery for a total of 146 renal cell cancer metastases. Clinical and radiographic data encompassing a 14-year treatment interval were collected. Multivariate analyses were used to determine significant prognostic factors influencing survival. The overall median length of survival was 15 months (range 1-65 months) from the diagnosis of brain metastasis. After radiosurgery, the median survival was 13 months in patients without and 5 months in those with active extracranial disease. In a multivariate analysis, factors significantly affecting the rate of survival included the following: 1) younger patient age (p = 0.0076); 2) preoperative Karnofsky Performance Scale score (p = 0.0012); 3) time from initial cancer diagnosis to brain metastasis diagnosis (p = 0.0017); 4) treatment dose to the tumor margin (p = 0.0252); 5) maximal treatment dose (p = 0.0127); and 6) treatment isodose (p = 0.0354). Prior tumor resection, chemotherapy, immunotherapy, or whole-brain radiation therapy did not correlate with extended survival. Postradiosurgical imaging of the brain demonstrated that 63% of the metastases had decreased, 33% remained stable, and 4% eventually increased in size. Two patients (2.9%) later underwent a craniotomy and resection for a tumor refractory to radiosurgery or a new symptomatic metastasis. Eighty-three percent of patients died of progression of extracranial disease.

CONCLUSIONS

Stereotactic radiosurgery for treatment of renal cell carcinoma metastases to the brain provides effective local tumor control in approximately 96% of patients and a median length of survival of 15 months. Early detection of brain metastases, aggressive treatment of systemic disease, and a therapeutic strategy including radiosurgery can offer patients an extended survival.

Gamma knife radiosurgery for brain metastases: a primary therapeutic option

Object. The aim of this retrospective study was to assess the role of gamma knife radiosurgery (GKS) as a primary treatment for brain metastases by evaluating the results in particularly difficult cases such as oncotypes—which are unresponsive to radiation—cystic lesions, and highly critical locations such as the brainstem.

Methods. Treatment of 804 patients with 1307 solitary (29%), single (26%), and multiple (45%) brain metastases was evaluated. Treatment planning parameters were as follows: mean tumor volume 4.8 cm3 (range 0.01–21.5 cm3), mean prescription dose 20.6 Gy (range 12–29 Gy), and mean number of isocenters 6.5 (one–19). In unresponsive oncotypes such as melanoma and renal cell carcinoma, the mean target dosages were higher. Cystic metastatic lesions were initially stereotactically evacuated and then GKS was performed. Patients with brainstem metastases were treated with lower doses. Conventional radiotherapy was used in only a minority (14%) of selected cases. The overall median patient survival time was 13.5 months, and the 1-year actuarial local progression-free survival rate was 94%, with a mean palliation index and functional independence index of 53.8 and 52.5 weeks, respectively. The local tumor control rate was 93%, with a mean follow-up period of 14 months. In the overall series, and especially in the unresponsive oncotypes, systemic disease progression was the main limiting factor with regard to patient life expectancy.

Conclusions. Gamma knife radiosurgery seems to be the primary treatment option for patients harboring small-tomedium size (≤ 20-cm3) brain metastases with reasonable life expectancy and no impending intracranial hypertension. Results are better than with those obtained using whole-brain radiotherapy and comparable to the best selected surgery—radiation series, even in oncotypes unresponsive to therapeutic radiation, cystic tumors, and tumors located in the brain stem.

Gamma knife radiosurgery for renal cell carcinoma brain metastases

Object. The purpose of this study was to clarify the effectiveness of gamma knife radiosurgery (GKS) in achieving a partial or complete remission of so-called radioresistant metastases from renal cell carcinoma (RCC) and to propose guidelines for optimal treatment

Methods. During a 5-year period, 29 patients (19 male and 10 female) with 92 brain metastases from RCC underwent GKS. The median tumor volume was 4.7 cm3 (range 0.5–14.5 cm3). Fourteen patients (48%) also underwent whole-brain radiotherapy (WBRT) before GKS, and two patients (6.8%) after GKS. The mean GKS dose delivered to the 50% isodose at the tumor margin was 16.8 Gy (range 13–30 Gy). All cases were categorized according to the Recursive Partitioning Analysis (RPA) classification for brain metastases. Univariate analysis was performed to determine significant prognostic factors and survival.

The overall median survival was 7 months after GKS treatment. Age, sex, Karnofsky Performance Scale score, and controlled primary disease were not predictors of survival. Combined WBRT/GKS resulted in median survival of 18, 8.5, and 5.3 months for RPA Classes I, II, and III, respectively, compared with the median survival 7.1, 4.2, and 2.3 months for patients treated with WBRT alone.

Conclusions. These results suggest that WBRT combined with GKS may improve survival in patients with brain metastases from RCC. Furthermore, this improvement in survival was seen in all RPA classes.

Gamma-knife radiosurgery for brain metastasis of renal cell carcinoma: results in 42 patients

BACKGROUND

The present study provides data from clinical experience with gamma-knife radiosurgery (GK) in patients with brain metastasis from renal cell carcinoma (RCC) and shows the value of this less invasive treatment modality.

METHODS

Forty-two patients received GK. Twenty of the 42 cases had multiple brain metastases. Extracranial metastases were observed in the lung (38 cases), bone (12 cases), liver (9 cases), lymph node (5 cases) and skin (6 cases).

RESULTS

Neurological symptoms seen in 40 patients were rapidly improved after GK in 32 patients (80%). Magnetic resonance imaging (MRI) evaluation after GK in 32 patients showed the disappearance of brain tumor in 9 patients (28%). Complete response was obtained by GK in tumors up to 30 mm in diameter. Repeated GK for newly developed lesions was conducted in 11 patients. Extracranial tumor resection was conducted in 7 cases (lung: 3, skin: 2, liver: 1, adrenal: 1). Chemo-radiotherapy or immunotherapy was effective in 8 cases (lung: 5, liver: 2, bone: 1). The actual one-, two- and three-year survival rates were 44.9%, 16.8%, and 11.2%, respectively. The median survival time was 12.5 months. In univariate analysis, the patients with successfully treated extracranial metastases had significantly better prognosis. In multivariate analysis, the patients with Karnofsky performance scale (KPS) > or = 80%, who were treated by GK more than once and obtained complete response (CR) or partial response (PR) by GK, had significantly better prognosis.

CONCLUSION

Gamma-knife radiosurgery for RCC is an effective non-invasive modality of treatment. It offers a high local control rate and an improved quality of life and survival rate.

Repeated gamma knife surgery for multiple brain metastases from renal cell carcinoma

OBJECT

The aim of this study was to evaluate the therapeutic profile of repeated gamma knife surgery (GKS) for renal cell carcinoma that has metastasized to the brain on multiple occasions.

METHODS

Data from this study were culled from a single institution and cover a 6-year period of outpatient radiosurgery. A standard protocol for indication, dose planning, and follow up was established. In cases of distant or local recurrences, radiosurgery was undertaken repeatedly (up to six times in one individual). Seventy-five patients harboring 350 cerebral metastases were treated. Relief from pretreatment neurological symptoms occurred in 72% of patients within a few days or a few weeks after the procedure. The actuarial local tumor control rate after the initial GKS was 95%. In patients free from relapse of intracranial metastases after repeated radiosurgery, long-term survival was 91% after 4 years; median survival was 11.1+/-3.2 months after radiosurgery and 4.5+/-1.1 years after diagnosis of the primary kidney cancer. Survival following radiosurgery was independent of patient age and sex, side of the renal cell carcinoma, pretreatment of the cerebrum by using radiotherapy or surgery, number of brain metastases and their synchronization with the primary renal cell carcinoma, and the frequency of radiosurgical procedures. In contrast, survival was dependent on the patient's clinical performance score and the extracranial tumor status. Tumor bleeding was observed in seven patients (9%) and late radiation toxicity (LRT) in 15 patients (20%). Treatment-related morbidity was moderate and mostly transient. Late radiation toxicity was encountered predominantly in long-term survivors.

CONCLUSIONS

Outpatient repeated radiosurgery is an effective and only minimally invasive treatment for multiple brain metastases from renal cell cancer and is recommended as being the method of choice to control intracranial disease, especially in selected patients with limited extracranial disease. Physicians dealing with such patients should be aware of the characteristic aspects of LRT.

Stereotactic Radiosurgery for Patients with “Radioresistant” Brain Metastases

OBJECTIVE

Our aim was to evaluate the efficacy of stereotactic radiosurgery (SRS) for the treatment of patients with brain metastases that have been determined to be “radioresistant” on the basis of histological examination.

METHODS

We reviewed the medical records of 41 consecutive patients who presented with 83 brain metastases from radioresistant primaries and subsequently underwent SRS. All patients were followed until death or for a median of 31 months after SRS. Tumor histologies included renal cell carcinoma (16 patients), melanoma (23 patients), and sarcoma (2 patients). Eighteen patients (44%) had a solitary metastasis, and 23 patients (56%) had multiple metastases.

RESULTS

The median overall survival time was 14.2 months after SRS. On the basis of univariate analysis, systemic disease status (P = 0.006) and Radiation Therapy Oncology Group recursive partitioning analysis (RPA) class (P = 0.005) were associated with survival. The median survival time was 23.5 months for patients in RPA Class I status and 10.5 months for patients in RPA Class II or III status. There was a trend (P = 0.12) toward improved median survival for patients with renal cell carcinoma (17.8 mo) as compared with patients with melanoma (9.7 mo). Multivariate analysis showed RPA class (P = 0.038) and histological diagnosis of primary tumor (P &lt; 0.001) to be independent predictors for overall survival. In the 35 patients who underwent follow-up imaging, 9 (12%) of 73 tumors recurred locally. In 54% of the patients, distant brain failure (DBF) developed. Whole brain radiotherapy (WBRT) improved local control and decreased DBF, according to the univariate and multivariate analyses. Patients who received adjuvant WBRT in addition to SRS had 6-month actuarial local control of 100% as compared with 85% among those who did not receive WBRT (P = 0.018). Patients who received adjuvant WBRT with SRS had a 6-month actuarial DBF rate of 17%, as compared with a rate of 64% among patients who had SRS alone (P = 0.0027).

CONCLUSION

Well-selected patients with brain metastases from radioresistant primary tumors who undergo SRS survive longer than historical controls. RPA Class I status and primary renal cell carcinoma predict longer survival. Adjuvant WBRT improves local control and decreases DBF but does not affect overall survival. Further studies are needed to determine which patients should receive WBRT.

Fractionated radiosurgery for brain metastases in 43 patients with breast carcinoma

About 15% of metastatic breast carcinoma patients are diagnosed with brain metastases. Historically, the majority are treated with palliative external whole-brain radiation with a median survival of 4 months. We examined stereotactic radiosurgery's effect on treatment outcome in such patients. Four hundred and fifty four consecutive patients with brain metastases were treated with stereotactic radiosurgery at Staten Island University Hospital, NY, between 1991 and 1999. The medical records of 60 women with histologically confirmed breast cancer were retrospectively reviewed. Forty-three patients (71%) received fractionated radiosurgery (4 x 600 cGy) and form the core of this report. Sixty five percentage had been previously unsuccessfully treated by whole-brain radiation or had recurrence after craniotomy. Survival was calculated by the Kaplan-Meier method. The median age at diagnosis of brain metastases was 52 years, with median interval of 49 months following the diagnosis of tumor primary. Median survival from brain diagnosis reached 13.6 months. Overall median survival from radiosurgery treatment was 7.5 months. Fifteen patients with one or two brain lesions survived a median of 11.5 months. For the fractionated cohort of patients 1- and 2-year actuarial survival was 28.2% and 12.8%, respectively. Three patients are alive at 32, 34 and 64 months, respectively. We conclude that fractionated radiosurgery improves survival of patients with brain metastases from breast cancer, especially those with small lesions, good functional status and no other metastatic disease. These patients should be encouraged to consider radiosurgery, possibly before WBRT. Considering our 7.5 months overall survival including patients with multiple metastases, and patients with progressive brain metastases despite extensive standard therapy and often systemic disease, these results suggest that radiosurgery could benefit breast cancer patients with brain metastases and extend life.

The role of whole brain radiotherapy and stereotactic radiosurgery on brain metastases from renal cell carcinoma

PURPOSE

We reviewed our experience with patients who have undergone stereotactic radiosurgery (SRS) for brain metastases secondary to renal cell carcinoma (RCC). Analysis was performed to determine the survival, local control, distant brain failure (DBF), and then to define which tumors may not require upfront whole-brain radiotherapy (WBRT).

METHODS AND MATERIALS

Twenty-nine patients with 66 tumors underwent SRS from 1991 to 1998. Median follow-up from time of brain metastases diagnoses relative to each tumor was 12.5 months and 6.8 months from the time of SRS. Median SRS dose was 1,800 cGy to the 60% isodose line. Three patients had undergone SRS for previously treated tumors.

RESULTS

Median survival time from diagnosis was 10.0 months. Overall survival was not affected by age, addition of WBRT, number of lesions, tumor volume, or the presence of systemic disease. Of the 23 patients with follow-up neuroimaging, 4 of 47 (9%) tumors recurred. The addition of WBRT did not improve local control. Of the 13 patients who presented with a single lesion, 3 went on to develop DBF (23%), while 6 of the 10 patients who presented with multiple metastases developed DBF (60%).

CONCLUSION

Patients with brain metastases secondary to RCC treated by SRS alone have excellent local control. The decision of whether or not to add WBRT to SRS should depend on whether the patient has a high likelihood of developing DBF. Our study suggests that patients who present with multiple brain lesions may be more likely to benefit from the addition of WBRT because they appear to be more than twice as likely to develop DBF as compared to patients with a single lesion.

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.

Diagnostic accuracy of MRI compared to CCT in patients with brain metastases

OBJECTIVES

In patients with extracranial neoplasms, the occurrence and number of brain metastases (BM) are critical for further diagnostic approaches and therapeutic strategies and the patient's prognosis. Although widely accepted, there is surprisingly little evidence in the literature that MRI is superior to CCT. Therefore, in patients with solitary BM according to diagnostic contrast-enhanced computed tomography (CCT), we investigated, what additional information could be gained by contrast-enhanced magnetic resonance imaging (MRI).

METHODS/RESULTS

Among 55 patients with solitary BM according to CCT, 17 had multiple BM on MRI (31%) and 38 had solitary BM in both. Based on a presumed binomial distribution of our data, we calculated a rate of at least 19% of patients with solitary BM on CCT, in which MRI would show multiple lesions (p = 0.05). The two main characteristics for BM missed by CCT were the smaller diameter, which averages 2 cm less than in BM identified with both modalities, and a preferential frontotemporal location.

CONCLUSION

MRI is indeed superior to CCT in the diagnosis of BM the essential reasons besides detection of smaller lesions being a better soft tissue contrast, significantly stronger enhancement with paramagnetic contrast agents, the lack of bone artifacts, fewer partial volume effects, and direct imaging in three different planes. Therefore, MRI is indispensable in the diagnostic workup of patients with BM for choosing the optimum therapeutic approach, especially with regard to the decision whether to operate or to primarily irradiate the patient's metastases.

Prognostic factor analysis for multiple brain metastases after gamma knife radiosurgery: results in 97 patients

Stereotactic radiosurgery (SR) is being used with increasing frequency in the treatment of brain metastases. This study provides data from a clinical experience with radiosurgery in the treatment of cases with multiple metastases and identifies parameters that may be useful in the proper selection and therapy of these patients. From January 1993 to April 1997, 97 patients (43 women and 54 men; median age 58 years) suffering from multiple brain metastases (median 3; range 2-4) in MRI scans, received SR with the Gamma Knife. The median dose at the tumor margin was 20 Gy (range 17-30 Gy). Median tumor volume was 3900 cmm (range 100-10,000). Different forms of hemiparesis, focal and generalized seizures, cognitive deficit, headache, dizziness and ataxia had been the predominant neurological symptoms. Major histologies included lung carcinoma (44%), breast cancer (21%), renal cell carcinoma (10%), colorectal cancer (8%), and melanoma (7%). The median survival time was 6 months after SR. The actual one-year survival rate was 26%. In univariate and multivariate analysis, a higher Karnofsky performance rating and absence of extracranial metastases had a significantly positive effect on survival. Local tumor control was achieved in 94% of the patients. Complications included the onset of peritumoral edema (n = 5) and necrosis (n = 1). SR induces a significant tumor remission accompanied by neurological improvement and, therefore, provides the opportunity for prolonged high quality survival. We conclude that radiosurgical treatment of multiple brain metastases leads to an equivalent rate of survival when compared to the historic experience of patients treated with whole brain radiotherapy. Patients presenting initially with a higher Karnofsky performance rating and without extracranial metastases had a median survival time of nine months. Each such case should therefore be evaluated based on these factors to determine an optimal treatment regimen.