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

Heterogeneous drug target expression as possible basis for different clinical and radiological response to the treatment of primary and metastatic renal cell carcinoma: suggestions from bench to bedside

Metastatic disease occurs in a significant percentage of patients with renal cell carcinoma (RCC) and is usually associated with an overall poor prognosis. However, not all of the sites of metastases seem to have the same prognostic significance in patients receiving targeted agents. Indeed, patients with lung-only metastases seem to present a better survival than patients with other sites, whereas liver and bone metastases are associated with a worst prognosis. Some clinical studies suggest that metastatic sites are more responsive than primary tumors. This event may be due to intratumor heterogeneity in terms of somatic mutations, chromosome aberrations, and tumor gene expression, primarily centered around Von Hippel-Lindau (VHL) pathway, such as VHL mutations, HIF levels, vascular endothelial growth factor (VEGF) isoforms, and VEGF receptor levels. Nevertheless, these data do not completely explain the discordant biological behavior between primary tumor and metastatic sites. Understanding the causes of this discordance will have profound consequences on translational research and clinical trials in RCC. In this review, we overview current data on the differences between primary RCC and metastases in terms of drug target expression and clinical/radiological response to targeted agents, thus describing the prognostic role of different metastatic sites in RCC patients.

Evaluation of tyrosine kinase receptors in brain metastases of clear cell renal cell carcinoma reveals cMet as a negative prognostic factor

AIMS

Brain metastases (BMs) of clear cell renal cell carcinoma (ccRCC) are associated with a dismal prognosis, with limited treatment options. Tyrosine kinases are relevant 'druggable' biomarkers. The aim of this study was to evaluate the tyrosine kinase receptors anaplastic lymphoma kinase (ALK), epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor-α (PDGFRA) and cMet in a large series of ccRCC BMs.

METHODS AND RESULTS

ALK, EGFR, PDGFRA and cMet protein expression was determined by immunohistochemistry in 53 ccRCCs BMs and 12 matched primary tumours. ALK and MET gene status and copy number alterations of chromosome 7 were studied with fluorescence in-situ hybridization (FISH). Data on the expression of hypoxia-inducible factor 1α (HIF1α) and Ki67 and microvessel density were available from previous studies. ALK was negative in all analysed specimens. EGFR was overexpressed in 41 of 51 (80.4%) BMs and in seven of eight primary tumours, PDGFRA was overexpressed in all BMs except one and in all primary tumours, and cMet was expressed in 26 of 50 (52%) BMs and in two of seven primary tumours, and did not correlate with MET amplification or polysomy 7. cMet was the only parameter associated with significantly shorter BM-specific survival (median 8 months versus 33 months, P = 0.005, Cox regression).

CONCLUSIONS

EGFR, PDGFRA and cMet are commonly overexpressed in ccRCC BMs. cMet overexpression correlates with significantly shorter BM-specific survival.

Incidence of local in-brain progression after supramarginal resection of cerebral metastases

BACKGROUND

Microsurgical circumferential stripping of intracerebral metastases is often insufficient in achieving local tumor control. Supramarginal resection may improve local tumor control.

METHODS

A retrospective analysis was performed for patients who underwent supramarginal resection of a cerebral metastasis by awake surgery with intraoperative cortical and subcortical stimulation, MEPs, and SSEPs. Supramarginal resection was achieved by circumferential stripping of the metastasis and additional removal of approximately 3 mm of the surrounding tissue. Pre- and postsurgical neurological status was assessed by the NIH Stroke Scale. Permanent deficits were defined by persistence after 3-month observation time.

RESULTS

Supramarginal resection of cerebral metastases in eloquent brain areas was performed in 34 patients with a mean age of 60 years (range, 33-83 years). Five out of 34 patients (14.7%) had a new transient postoperative neurological deficit, which improved within a few days due to supplementary motor area (SMA) syndrome. Five out of 34 patients (14.7%) developed a local in-brain progression and nine patients (26.4%) a distant in-brain progression.

CONCLUSIONS

Supramarginal resection of cerebral metastases in eloquent locations is feasible and safe. Safety might be increased by intraoperative neuromonitoring. The better outcome in the present series may be entirely based on other predictors than extend of surgical resection and not necessarily on the surgical technique applied. However, supramarginal resection was safe and apparently did not lead to worse results than regular surgical techniques. Prospective, controlled, and randomized studies are mandatory to determine the possible benefit of supramarginal resection on local tumor control and overall outcome.

Smad4 suppresses the progression of renal cell carcinoma via the activation of forkhead box protein H1

Smad4 has recently been identified as a tumor suppressor gene in a variety of cancers, yet the role of Smad4 in renal cell carcinoma (RCC) remained to be elusive. Therefore, the aim of the present study was to explore the function of Smad4 in RCC. The expression of Smad4 reduced the growth rate of RCC. The levels of Smad4 and forkhead box protein H1 (FOXH1) mRNA were reduced, while the levels of estrogen receptor were increased in RCC cells compared with those in human renal epithelial cells (P<0.01). Western blot analysis showed an identical trend among the three molecules. Glutathione S‑transferase pull‑down and immunoprecipitation assays proved the interaction between Smad4 and FOXH1. An immunofluorescence assay revealed that Smad4 and FOXH1 were colocalized in the nuclei of RCC cells. Smad4 interacts with Smad2 and migrates into the nucleus, where it interacts with FOXH1 to repress the protein expression of estrogen receptor. These results indicate that Smad4 acts as a tumor suppressor by activating FOXH1, and then suppressing the expression of estrogen receptor, in addition to tumor migration and invasion. Hence, Smad4 should be investigated as a potential target for the treatment for RCC.

The biology of radiosurgery and its clinical applications for brain tumors

Stereotactic radiosurgery (SRS) was developed decades ago but only began to impact brain tumor care when it was coupled with high-resolution brain imaging techniques such as computed tomography and magnetic resonance imaging. The technique has played a key role in the management of virtually all forms of brain tumor. We reviewed the radiobiological principles of SRS on tissue and how they pertain to different brain tumor disorders. We reviewed the clinical outcomes on the most common indications. This review found that outcomes are well documented for safety and efficacy and show increasing long-term outcomes for benign tumors. Brain metastases SRS is common, and its clinical utility remains in evolution. The role of SRS in brain tumor care is established. Together with surgical resection, conventional radiotherapy, and medical therapies, patients have an expanding list of options for their care. Clinicians should be familiar with radiosurgical principles and expected outcomes that may pertain to different brain tumor scenarios.

Durable control of locally recurrent renal cell carcinoma using stereotactic body radiotherapy

Renal cell carcinoma (RCC) is generally poorly responsive to conventional radiation doses, and patients with inoperable local recurrence have limited therapeutic options. Stereotactic body radiotherapy (SBRT) is an increasingly available technology that allows delivery of a radiation schedule providing doses far more biologically effective against cancer cells than conventional radiotherapy. We present a case where durable disease control was achieved using SBRT in a patient with inoperable locally recurrent RCC who presented 18 years from original nephrectomy. The patient remains asymptomatic with no evidence of active disease 30 months following SBRT. This case highlights the need to reconsider the role of therapies with continuing advances in technology.

The ventricular system and choroid plexus as a primary site for renal cell carcinoma metastasis

BACKGROUND

Brain metastases (BM) are the most common intracranial tumours amongst adults. Ten to 40 % of patients with cancer will develop BM. In this study, we observed a high affinity of renal cell carcinoma (RCC) to the ventricular system, with close association to the choroid plexus.

METHODS

This is a retrospective study evaluating data of our prospectively maintained brain tumour database, focusing on consecutive BM patients, who were treated at our center between March 2003 and December 2011. Data collected included primary pathologies, anatomical distribution of the brain metastasis according to neuroimaging, and treatment modalities.

RESULTS

We identified 614 patients with BM, of whom 24 (3.9 %) were diagnosed with RCC, harboring 33 lesions. Nine of the 24 patients (37.5 %) presented with an intraventricular location (10 of 33 RCC BM lesions). Of the remaining 590 patients with non-RCC pathologies, five patients (0.8 %) were diagnosed with intraventricular lesions (p < 0.0001).

CONCLUSION

In this unselected, consecutive treated BM patient cohort we observed a high affinity of RCC BM to the ventricular system with close association to the choroid plexus. The reason for this affinity is unknown. Surgical approaches for resection of these lesions should be planned to include early control on the vascular supply from the choroidal vessels.

Long term outcome of Gamma Knife radiosurgery for metastatic brain tumors

Gamma Knife radiosurgery (GKRS; Elekta AB, Stockholm, Sweden) has emerged as an important treatment option for metastatic brain tumors (MBT). However, the long term outcome of GKRS on MBT is not well understood. We reviewed the treatment of MBT with GKRS at our institution. We performed a retrospective review (2000-2013) of 298 patients with MBT who received GKRS. The study population was monitored clinically and radiographically after GKRS treatment. Survival benefits and predictive factors of the outcome were analyzed using the Kaplan-Meier test and Cox regression model, respectively. GKRS in MBT showed significant variation in tumor growth control (decreased in 135 [45%] patients, arrested growth in 91 [37%] patients and increased tumor size in 72 [24%] patients). The median survival in the study population was 17 months. Overall and progression free survival after 3 years were 25% and 45%, respectively. The predictive factors for improving survival in the patients with MBT were recursive partitioning analysis class I (p<0.0001), absence of hydrocephalus (p<0.0001), Karnofsky Performance Status (KPS) >80 (p=0.007) and absence of recurrent MBT (p=0.01). Forty (12%), 15 (4.3%) and two (0.6%) patients required GKRS, resection and whole brain radiation, respectively, after initial GKRS due to tumor progression and worsening of signs and symptoms. Our findings revealed that GKRS offers a high rate of tumor control and good survival benefits in both new and recurrent patients with MBT. Thus, GKRS is an effective treatment option for new patients with MBT, as well as an adjuvant therapy in patients with recurrent MBT.

Impact of the number of metastatic brain lesions on survival after Gamma Knife radiosurgery

Effectiveness of Gamma Knife radiosurgery (GKRS: Elekta AB, Stockholm, Sweden) for patients with metastatic brain disease and the prognostic factors influencing their survival were analyzed in a 5 year retrospective data analysis (July 2001 to June 2006). Kaplan-Meier survival curves were constructed using univariate and multivariate analyses with the respective salient prognostic factors. This study analyzed data on 330 patients with brain metastases who underwent GKRS. Lung carcinoma (55%) was the most common primary cancer followed by breast (17.8%), melanoma (9.4%), colorectal (4.8%) and renal (3.9%). The median survival for all patients was 8 months. Survival ranged from 13 months for breast metastases, 10 months for renal, and 8 months for lung to 5 months for colorectal and melanoma. Mean age of patients was 58.5 years (range 18-81). Melanoma patients were younger with a mean age of 49 and also had the highest number of lesions (3.8) when compared to patients with renal (2.5), lung (2.8), colorectal (3) and breast (3.6). When stratified according to the number of lesions patient survival was 8 months (one to three lesions), 7.5 months (four or five lesions) and 7 months (six lesions or more). Mean Karnofsky Performance Status score (KPS) was 77 and survival dropped significantly from 8 months to 4.5 months if KPS was less than 70. Survival improved with a KPS of 70 or more, regardless of the number of lesions treated. Selection of patients based on the number of lesions may not be justified. A prospective trial is required to further define the prognostic factors affecting survival.

Stereotactic radiosurgery (SRS) for brain metastases: a systematic review

In many patients with brain metastases, the primary therapeutic aim is symptom palliation and maintenance of neurologic function, but in a subgroup, long-term survival is possible. Local control in the brain, and absent or controlled extracranial sites of disease are prerequisites for favorable survival. Stereotactic radiosurgery (SRS) is a focal, highly precise treatment option with a long track record. Its clinical development and implementation by several pioneering institutions eventually rendered possible cooperative group randomized trials. A systematic review of those studies and other landmark studies was undertaken. Most clinicians are aware of the potential benefits of SRS such as a short treatment time, a high probability of treated-lesion control and, when adhering to typical dose/volume recommendations, a low normal tissue complication probability. However, SRS as sole first-line treatment carries a risk of failure in non-treated brain regions, which has resulted in controversy around when to add whole-brain radiotherapy (WBRT). SRS might also be prescribed as salvage treatment in patients relapsing despite previous SRS and/or WBRT. An optimal balance between intracranial control and side effects requires continued research efforts.

Evaluation of results of linac-based radiosurgery for brain metastases from primary lung cancer

AIM

The purpose of our review was to evaluate results of radiosurgery for patients with brain metastases from lung cancer.

BACKGROUND

Lung cancer is the leading cause of death from cancer and the most common source of brain metastases. Radiosurgery allows the precise focal delivery of a high single radiation dose to brain metastases and results in high rates of local control.

MATERIALS AND METHODS

83 patients were treated between 2006 and 2008. We evaluated local control and outcome after radiosurgery and identified prognostic factors.

RESULTS

Median survival in the whole group was 7.8 months from radiosurgery and 11 months from diagnosis. Median survival in classes I, II and III was 13.2, 8.2 and 2.2 months. For 94% of patients symptoms improved or stabilised at the first follow-up visit and this status did not change during 7.1 months. According to the univariate analysis, factors associated with improved survival included: RPA class 1 compared with RPA 2 and 3, RPA class 2 compared with RPA 3, KPS > 70, control of the primary disease, radiosurgery performed more than once, level of haemoglobin >7 mmol/1, absence of extracranial metastases, volume of the biggest lesion <11 cm(3). The multivariate analysis confirmed a significant influence on survival for the following factors: RPA class 1 as compared with RPA 3, KPS > 70, absence of extracranial metastases, multiplicity of radiosurgery.

CONCLUSIONS

Stereotactic radiosurgery is a safe and effective treatment. It proved to be effective and safe in older patients. Selection of patients who are likely to benefit most should be based on prognostic factors. KPS proved to be the most important prognostic factor. In the RPA III group (patients with KPS < 70) survival time was similar to that achieved after symptomatic medical management.

Renal cell carcinoma treated with stereotactic radiotherapy with histological change confirmed on autopsy: a case report

Background

Treatment of primary renal cell carcinoma using radiotherapy with curative intent is rare, because renal cell carcinoma is generally regarded as a radiation-resistant tumor. Recently, stereotactic body radiation therapy has been radically applied for cancers in various organs including renal cell carcinoma. However, there were few reports describing pathological changes of renal cell carcinoma post stereotactic body radiation therapy. This is the first report we are aware of documenting late histological effects of stereotactic body radiation therapy on renal cell carcinoma and surrounding normal tissue.

Case presentation

A right renal tumor was identified in a Japanese 70-year-old man on follow-up computed tomography for his chronic hepatitis. T1N0M0 renal cell carcinoma was clinically diagnosed as the tumor was 3 cm in diameter and well-enhanced with intravenously infused contrast material in the arterial phase on computed tomography. No metastases in regional lymph nodes or distant sites were evident. Stereotactic body radiation therapy was selected as an alternative therapy to surgery because of his poor liver function. A total dose of 60 Gy in 10 fractions over 12 days was delivered using a 10-megavolt X-ray. The renal tumor gradually decreased in size and partial response had been achieved at 2 years after completing stereotactic body radiation therapy. Hepatocellular carcinoma was identified during follow-up in the patient and he died of progression of hepatocellular carcinoma with hepatic failure 2.5 years after completing stereotactic body radiation therapy. Autopsy was done and it showed almost complete necrosis of tumor tissues with a small amount of viable renal carcinoma cells. These pathological findings suggested marked effects of stereotactic body radiation therapy on clear cell renal cell carcinoma.

Conclusion

Our case demonstrates a good pathological response with small foci of remnant viable cancer cells after stereotactic body radiation therapy of 60Gy in 10 fractions for small renal cell carcinoma. Although further experiences and longer follow-up are mandatory to conclude the optimal treatment schedule and efficacy of stereotactic body radiation therapy for renal cell carcinoma, stereotactic body radiation therapy may represent a novel less-invasive option for the treatment of primary renal cell carcinoma.

It Is Time to Reevaluate the Management of Patients With Brain Metastases

There are many elements to the science that drives the clinical care of patients with brain metastases. Although part of an understanding that continues to evolve, a number of key historical misconceptions remain that commonly drive physicians' and researchers' attitudes and approaches. By understanding how these relate to current practice, we can better comprehend our available science to provide both better research and care. These past misconceptions include: Misconception 1: Once a primary cancer spreads to the brain, the histology of that primary tumor does not have much impact on response to chemotherapy, sensitivity to radiation, risk of further brain relapse, development of additional metastatic lesions, or survival. All tumor primary histologies are the same once they spread to the brain. They are the same in terms of the number of tumors, radiosensitivity, chemoresponsiveness, risk of further brain relapse, and survival. Misconception 2: The number of brain metastases matters. This number matters in terms of subsequent brain relapse, survival, and cognitive dysfunction; the precise number of metastases can also be used as a limit in determining which patients might be eligible for a particular treatment option. Misconception 3: Cancer in the brain is always a diffuse problem due to the presence of micrometastases. Misconception 4: Whole-brain radiation therapy invariably causes disabling cognitive dysfunction if a patient lives long enough. Misconception 5: Most brain metastases are symptomatic. Thus, it is not worth screening patients for brain metastases, especially because the impact on survival is minimal. The conduct and findings of past clinical research have led to conceptions that affect clinical care yet appear limiting.

Significance of histology in determining management of lesions regrowing after radiosurgery

Brain metastases treated with stereotactic radiosurgery may show delayed enlargement on post-treatment imaging that is of ambiguous etiology. Histopathologic interpretation of brain specimens is often challenging due to the presence of significant radiation effects admixed with irradiated residual tumor of indeterminate viability. The purpose of this study was to assess the impact of histologic findings on clinical outcomes following resection of these lesions. Between 2004 and 2010, 690 patients with brain metastases were enrolled in a prospective gamma knife data repository, and lesions requiring excision were identified. Tissue specimens were divided into four groups based on the ratio of treatment related inflammatory changes (TRIC) to tumor cells, and subsequently patient outcomes were assessed. Of 2,583 metastases treated, 36 were excised due to symptomatic enlargement. Only TRIC, without residual evidence of tumor, was seen in 36 % (13/36) of specimens. Resection of these lesions resulted in 100 % local control in follow-up. Of the remaining 23 lesions that contained any viable-appearing tumor within the resected specimen, 8 recurred after resection. Lesions that enlarged in the first 6 months were more likely to contain higher amounts of residual tumor cells. Patients with even <2 % tumors cells on excision had significantly worse local control (75 vs. 100 %, p = 0.024) and survival (HR 0.27, p = 0.029) compared with those patients with exclusively TRIC. In summary, our findings underscore the importance of surgically obtaining tissue in a method that facilitates complete lesional interpretive histology in order to accurately guide ongoing patient management.

The impact of tyrosine kinase inhibitors on the multimodality treatment of brain metastases from renal cell carcinoma

OBJECTIVES

This study evaluated the effect of tyrosine kinase inhibitors (TKIs) on the brain metastasis (BM), local control (LC), and overall survival (OS) of patients with renal cell carcinoma (RCC) with BM.

METHODS

A retrospective review of patients with RCC BM was conducted. Eligible patients from 2 eras: pre-TKI, 2002 to 2003 and post-TKI, 2006 to 2007, were identified. Prognostic factors, use, and type of systemic therapy were noted. The timing, number, size, and treatment modality data for each BM were recorded. Use of TKI and BM treatment modality were correlated to LC and OS.

RESULTS

Eighty-one patients with 216 BMs were identified. Thirty-seven patients had BM at diagnosis and the remaining 44 were found to have BM at a later point. Forty-one patients never received a TKI and the remaining 40 received TKIs. Stereotactic radiosurgery, surgery, whole brain radiotherapy, or no local brain treatment was used for 89, 19, 24, and 75 lesions, respectively. The median OS from BM diagnosis was 5.4 months for the whole group: 4.4 versus 6.71 months in the never-TKI versus TKI groups, respectively. Patients who received TKIs post-BM development had a median OS of 23.6 months versus 2.08 and 4.41 months for the patients who received TKIs pre-BM or never-TKI, respectively (P=0.0001). LC was statistically superior in lesions managed with surgery or stereotactic radiosurgery versus the no local therapy.

CONCLUSIONS

In patients with RCC and BM, TKIs are associated with a trend of improved OS, but no significant improvement in LC of BM. They may provide a significant benefit to patients with BM with no prior TKI exposure.

Patterns of recurrence and surveillance strategies for renal cell carcinoma following surgical resection

Renal cell carcinoma (RCC) remains one of the most lethal urologic malignancies, with up to 40% of patients eventually dying of cancer progression. Despite advances in the diagnosis, staging and treatment of patients with RCC, approximately a third of patients who undergo surgery for clinically localized RCC will suffer a recurrence. Timely identification of recurrences following surgical extirpation is imperative in the treatment of these patients. RCC is known to metastasize through hematogenous routes of spread to distant organ sites and via lymphatic channels to regional lymph nodes. The path of tumor escape is associated with diverse clinical outcomes and a unique tumor biology. A consensus on surveillance regimens for patients following surgical resection of localized disease is lacking. The most extensively used system for providing prognostic information regarding survival and recurrence of disease has historically been the tumor-node-metastasis (TNM) classification system. As a result, most contemporary surveillance protocols have tailored follow-up regimens according to stage-based stratifications. Numerous studies have recently demonstrated that certain clinical and histopathological factors can improve the prediction of tumor recurrence. The incorporation of these prognostic factors into stage-based stratification models should be better than stage alone in attempting to provide a rational approach to identifying treatable recurrences while minimizing unnecessary exams and tests, as well as patient anxiety. Advances in the understanding of the pathogenesis, behavior and molecular biology of RCC have paved the way for developments that may enhance early diagnosis and prognostication, and improve survival for patients. Lastly, molecular markers should, in the future, revolutionize surveillance protocols for RCC by tailoring follow-up to specific molecular classifications.

Treatment of brain metastases in uncommon tumors

Melanoma spreads to the CNS with an incidence of 4 to 20%. Metastases from cancer of the colorectal and genitourinary tract, as well as sarcoma, are less frequent (1%). Surgery should be considered for single brain metastases in patients with controllable disease. Stereotactic needle biopsy may still be worthwhile to confirm diagnosis, and also in patients whose tumors are considered unresectable. Whole-brain radiotherapy is the treatment of choice for most brain metastases, since more than 70% of patients have multiple metastases at the time of diagnosis. Radiosurgery is particularly useful for patients unable to tolerate surgery and for patients with lesions inaccessible to surgery. Chemotherapy could be useful in patients with asymptomatic brain metastases and uncontrolled extracranial disease, depending on performance status and previous chemotherapy received.

Renal cell carcinoma metastasis to the cerebellopontine cistern: intraoperative Onyx embolization via direct needle puncture

We report a rare case of a renal cell carcinoma (RCC) metastasis occupying the cerebellopontine and cerebellomedullary cisterns, and describe an alternative strategy for embolizing hypervascular intracranial tumors. A middle aged patient with a distant history of RCC presented with headaches, nausea, and vomiting, and was found to have an enhancing mass in the left cerebellopontine and cerebellopontine cisterns. The initial surgical resection was aborted due to excessive bleeding. After an unsuccessful attempt at intra-arterial embolization, the patient returned to the operating room and the tumor was devascularized by direct needle puncture Onyx embolization under biplane fluoroscopy. The devascularized tumor was then successfully dissected from the brainstem and adherent lower cranial nerves. In properly selected cases, open surgical direct needle puncture embolization of intracranial vascular tumors under biplane fluoroscopy is a viable alternative devascularization method.

Renal cell carcinoma metastasis to the cerebellopontine cistern: intraoperative Onyx embolization via direct needle puncture

We report a rare case of a renal cell carcinoma (RCC) metastasis occupying the cerebellopontine and cerebellomedullary cisterns, and describe an alternative strategy for embolizing hypervascular intracranial tumors. A middle aged patient with a distant history of RCC presented with headaches, nausea, and vomiting, and was found to have an enhancing mass in the left cerebellopontine and cerebellopontine cisterns. The initial surgical resection was aborted due to excessive bleeding. After an unsuccessful attempt at intra-arterial embolization, the patient returned to the operating room and the tumor was devascularized by direct needle puncture Onyx embolization under biplane fluoroscopy. The devascularized tumor was then successfully dissected from the brainstem and adherent lower cranial nerves. In properly selected cases, open surgical direct needle puncture embolization of intracranial vascular tumors under biplane fluoroscopy is a viable alternative devascularization method.

Extremely delayed brain metastasis from renal cell carcinoma

Brain metastasis occurs in 3.9-24% of patients with renal cell carcinoma (RCC), with an average interval from nephrectomy to brain metastasis of 1 to 3 years. A few cases have been reported where brain metastasis occurred after a delay of more than 10 years from the initial onset of renal cell carcinoma. This long interval for central nervous system metastasis from the primary cancer has been recognized as an indicator of better prognosis. Histopathological confirmation and aggressive treatment must be considered in these delayed brain metastases cases, since the patients usually show long survival and good prognosis. We present a case of a 76-year-old woman who developed extremely late multiple brain metastases 18 years after a nephrectomy for RCC.

Stereotactic radiosurgery in the treatment of brain metastases: the current evidence

Chemotherapy has made substantial progress in the therapy of systemic cancer, but the pharmacological efficacy is insufficient in the treatment of brain metastases. Fractionated whole brain radiotherapy (WBRT) has been a standard treatment of brain metastases, but provides limited local tumor control and often unsatisfactory clinical results. Stereotactic radiosurgery using Gamma Knife, Linac or Cyberknife has overcome several of these limitations, which has influenced recent treatment recommendations. This present review summarizes the current literature of single session radiosurgery concerning survival and quality of life, specific responses, tumor volumes and numbers, about potential treatment combinations and radioresistant metastases. Gamma Knife and Linac based radiosurgery provide consistent results with a reproducible local tumor control in both single and multiple brain metastases. Ideally minimum doses of ≥18Gy are applied. Reported local control rates were 90-94% for breast cancer metastases and 81-98% for brain metastases of lung cancer. Local tumor control rates after radiosurgery of otherwise radioresistant brain metastases were 73-90% for melanoma and 83-96% for renal cell cancer. Currently, there is a tendency to treat a larger number of brain metastases in a single radiosurgical session, since numerous studies document high local tumor control after radiosurgical treatment of >3 brain metastases. New remote brain metastases are reported in 33-42% after WBRT and in 39-52% after radiosurgery, but while WBRT is generally applied only once, radiosurgery can be used repeatedly for remote recurrences or new metastases after WBRT. Larger metastases (>8-10cc) should be removed surgically, but for smaller metastases Gamma Knife radiosurgery appears to be equally effective as surgical tumor resection (level I evidence). Radiosurgery avoids the impairments in cognition and quality of life that can be a consequence of WBRT (level I evidence). High local efficacy, preservation of cerebral functions, short hospitalization and the option to continue a systemic chemotherapy are factors in favor of a minimally invasive approach with stereotactic radiosurgery.

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.

Surgical resection of urological tumor metastases following medical treatment

BACKGROUND

The rate of systemic metastases is about 20% in testicular germ cell tumors, 25% to 30% in prostate cancer, 30% in urothelial carcinoma with muscle invasion, and 50% in renal-cell carcinoma. This article is a critical review of current data on the resection of metastases of urological tumors after systemic drug treatment.

METHODS

Review of pertinent publications retrieved by a selective literature search.

RESULTS

No pertinent prospective, randomized trials, meta-analyses, or Cochrane reviews have been published. The publications available for review include guidelines and retrospective studies with evidence levels ranging from IIB to III. For non-seminomatous germ cell tumors with tumor markers that are negative or have reached a plateau after chemotherapy, resection of retroperitoneal, intra-abdominal, and intrathoracic metastases with curative intent is now the treatment of choice at clinical reference centers. For urothelial carcinoma that has gone into partial remission after systemic chemotherapy, with full resectability, the resection of metastases prolongs survival from about 13 months to 31-41 months. For prostatic carcinoma with solitary, intrapelvic lymph-node metastases and PSA less than 4 ng/mL, the resection of metastases prolongs 5-year progression-free survival in 40% to 50% of cases. There is, however, no indication for the resection of retro-peritoneal, visceral, or bony metastases. In renal-cell carcinoma, the resection of pulmonary or hepatic metastases is associated with a 5-year survival rate of 40% to 50% or 62%, respectively, and should thus be made a component of the treatment plan for this disease. The indication for resecting metastases of urological cancers should always be established by an interdisciplinary tumor board in the light of the existing scientific evidence.

CONCLUSION

The resection of metastases of some types of urological cancer after chemotherapy can prolong progression-free and overall survival. This form of treatment deserves consideration as a component of individual care and of the interdisciplinary treatment plan for urological cancers.

Gamma knife surgery for brain metastases from ovarian cancer

Background

Brain metastases from ovarian cancer are rare, but their incidence is increasing. The purpose of this study was to investigate the characteristics of brain metastases from ovarian cancer, and to assess the efficacy of treatment with gamma knife surgery (GKS).

Methods

A retrospective review was performed of patients with brain metastases from ovarian cancer who were treated at the Tokyo Gamma Unit Center from 2006 to 2010.

Results

Sixteen patients were identified. Their median age at diagnosis of brain metastases was 56.5 years, the median interval from diagnosis of ovarian cancer to brain metastases was 27.5 months, and the median number of brain metastases was 2. The median Karnofsky Performance Score (KPS) at the first GKS was 80. The median survival following diagnosis of brain metastases was 12.5 months, and 6-month and 1-year survival rates were 75 % and 50 %, respectively. The tumor control rate was 86.4 %. The KPS (<80 vs ≥80) and total volume of brain metastases (<10 cm³ vs ≥10 cm³) were significantly associated with survival according to a univariate analysis (p = 0.004 and p = 0.02, respectively).

Conclusions

The results of this study suggest that GKS is an effective remedy and acceptable choice for the control of brain metastases from ovarian cancer.

Novel agents in renal carcinoma: a reality check

The discovery of the molecular mechanisms underlying development of renal cell carcinoma have allowed for the development of novel targeted therapy for treatment of this disease. Recently, multiple agents have become approved by regulatory authorities for the treatment of advanced renal cell carcinoma, including sunitinib, sorafenib, bevacizumab (with interferon alpha), pazopanib, temsirolimus and everolimus. While these therapies have generated excitement and have clearly altered the treatment paradigm, multiple limitations have been elucidated over time. These include but are not limited to the fact that treatment is not associated with complete responses, a significant number of patients are primarily refractory to treatment, and clinical trials mostly include clear cell histology. Furthermore, the role of these therapies in the treatment of brain metastases remains unclear and therapies can have considerable toxicities. RECIST criteria (Response Evaluation Criteria In Solid Tumors) can be inadequate for the assessment of these modalities' treatment efficacy, and biomarkers predictive of individual patient benefit have been elusive. This review summarizes the major clinical data and discusses these limitations.

[Metastasectomy for renal cell cancer]

BACKGROUND

Metastasectomy prior to or after systemic medical cancer treatment is performed within a multimodal therapeutic approach in metastatic renal cell cancer (mRCC) to improve the prognosis. The role of metastasectomy in mRCC is controversially discussed and the potential therapeutic benefit is unquantifiable. The purpose of the current review is to critically discuss the available data.

METHODS

A systematic literature search was carried out in the MedLinedatabase to identify original publications, review articles and editorials with respect to metastasectomy in mRCC and the current European guidelines were also taken into consideration.

RESULTS

Metastasectomy is one of the approaches for mRCC recommended in the guidelines in cases of stable disease for at least 3 months, complete resectability of all metastatic lesions independent of the anatomic localization and a good performance status of the patient. The median survival time varies between 35 and 55 months.

CONCLUSIONS

In mRCC metastasectomy is an indiviudal therapeutic approach which might be considered for limited metastatic disease and the presence of good prognostic risk factors to improve average survival time. Especially in renal cell cancer metastasectomy should be considered early.

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.

The effect of targeted agents on outcomes in patients with brain metastases from renal cell carcinoma treated with Gamma Knife surgery

OBJECT

Gamma Knife surgery (GKS) has been reported as an effective modality for treating brain metastases from renal cell carcinoma (RCC). The authors aimed to determine if targeted agents such as tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, and bevacizumab affect the patterns of failure of RCC after GKS.

METHODS

Between 1999 and 2010, 61 patients with brain metastases from RCC were treated with GKS. A median dose of 20 Gy (range 13-24 Gy) was prescribed to the margin of each metastasis. Kaplan-Meier analysis was used to determine local control, distant failure, and overall survival rates. Cox proportional hazard regression was performed to determine the association between disease-related factors and survival.

RESULTS

Overall survival at 1, 2, and 3 years was 38%, 17%, and 9%, respectively. Freedom from local failure at 1, 2, and 3 years was 74%, 61%, and 40%, respectively. The distant failure rate at 1, 2, and 3 years was 51%, 79%, and 89%, respectively. Twenty-seven percent of patients died of neurological disease. The median survival for patients receiving targeted agents (n = 24) was 16.6 months compared with 7.2 months (n = 37) for those not receiving targeted therapy (p = 0.04). Freedom from local failure at 1 year was 93% versus 60% for patients receiving and those not receiving targeted agents, respectively (p = 0.01). Multivariate analysis showed that the use of targeted agents (hazard ratio 3.02, p = 0.003) was the only factor that predicted for improved survival. Two patients experienced post-GKS hemorrhage within the treated volume.

CONCLUSIONS

Targeted agents appear to improve local control and overall survival in patients treated with GKS for metastastic RCC.

A comprehensive review of MR imaging changes following radiosurgery to 500 brain metastases

BACKGROUND AND PURPOSE

Stereotactic radiosurgery is known to control 85%-95% of intracranial metastatic lesions during a median survival of 6-8 months. However, with the advent of newer systemic cancer therapies, survival is improving; this change mandates a longitudinal quantitative analysis of the radiographic response of brain metastases to radiosurgery.

MATERIALS AND METHODS

MR imaging of 516 metastases in 120 patients treated with GK-SRS from June 2006 to December 2009 was retrospectively reviewed. Lesion volume at initial treatment and each follow-up was calculated by using the following formula: length × width × height / 2. Volume changes were correlated with patient demographics, histopathology, and radiation treatment variables.

RESULTS

Thirty-two percent of lesions increased in volume following radiosurgery. Clinically, this translated into 54% of patients having ≥1 of their lesions increase in size. This increase begins at 6 weeks and can last beyond 15 months' post-SRS. Male sex (P = .002), mean voxel dose <37 Gy (P = .009), and initial treatment volume >500 mm(3) (P < .001) are associated with posttreatment increases in tumor size. Median survival following radiosurgery was 9.5 months for patients with all lesions exhibiting stable/decreased volumes, >18.4 months for patients with all lesions exhibiting increased volumes, and 16.4 months for patients with mixed lesional responses.

CONCLUSIONS

Most metastatic lesions are stable or smaller in size during the first 36 months post-SRS. However, a transient increase in volume is seen in approximately one-third of lesions. Sex, treatment dose, initial lesion size, and histopathology all correlate with variations in lesion volume post-SRS. The longer the patient survives, the more likely an increase in lesion size will be seen on follow-up imaging.

Role of radiation therapy in the management of renal cell cancer

Renal cell carcinoma (RCC) is traditionally considered to be radioresistant; therefore, conventional radiotherapy (RT) fraction sizes of 1.8 to 2 Gy are thought to have little role in the management of primary RCC, especially for curative disease. In the setting of metastatic RCC, conventionally fractionated RT has been an effective palliative treatment in 50% of patients. Recent technological advances in radiation oncology have led to the clinical implementation of image-guided radiotherapy, allowing biologically potent doses to the tumors intra- and extra-cranially. As predicted by radiobiologic modeling, favorable outcomes have been observed with highly hypofractionated schemes modeled after the experience with intracranial stereotactic radiosurgery (SRS) for RCC brain metastases with reported local control rates averaging 85%. At present, both primary and metastatic RCC tumors may be successfully treated using stereotactic approaches, which utilize steep dose gradients to maximally preserve function and avoid toxicity of adjacent organs including liver, uninvolved kidney, bowel, and spinal cord regions. Future endeavors will combine stereotactic body radiation therapy (SBRT) with novel targeted therapies, such as tyrosine kinase inhibitors and targeted rapamycin (mTOR) inhibitors, to maximize both local and systemic control.

Distribution of metastatic sites in renal cell carcinoma: a population-based analysis

BACKGROUND

We assessed the distribution of site-specific metastases in patients with renal cell carcinoma (RCC) according to age. Moreover, we evaluated recommendations proposed by guidelines and focused specifically on bone and brain metastases.

PATIENTS AND METHODS

Patients with metastatic RCC (mRCC) were abstracted from the Nationwide Inpatient Sample (1998-2007). Age was stratified into four groups: <55, 55-64, 65-74 and ≥ 75 years. Cochran-Armitage trend test and multivariable logistic regression analysis tested the relationship between age and the rate of multiple metastatic sites. Finally, we examined the rates of brain or bone metastases according to the presence of other metastatic sites.

RESULTS

In 11,157 mRCC patients, the rate of multiple metastatic sites decreased with increasing age (P < 0.001). This phenomenon was confirmed in patients with lung, bone, liver and brain metastases (all P ≤ 0.01). The rate of bone metastases was 10% in patients with exclusive abdominal metastases and 49% in patients with abdominal, thoracic and brain metastases. The rate of brain metastases was 2% in patients with exclusive abdominal metastases and 16% in patients with thoracic and bone metastases.

CONCLUSIONS

The proportion of patients with multiple metastatic sites is higher in young patients. The rates of bone (10%-49%) and brain (2%-16%) metastases are nonnegligible in mRCC patients.

Multimodality treatment of brain metastases: an institutional survival analysis of 275 patients

Background

Whole brain radiation therapy (WBRT), surgical resection, stereotactic radiosurgery (SRS), and combinations of the three modalities are used in the management of patients with metastatic brain tumors. We present the previously unreported survival outcomes of 275 patients treated for newly diagnosed brain metastases at Cancer Care Northwest and Gamma Knife of Spokane between 1998 and 2008.

Methods

The effects treatment regimen, age, Eastern Cooperative Oncology Group-Performance Status (ECOG-PS), primary tumor histology, number of brain metastases, and total volume of brain metastases have on patient overall survival were analyzed. Statistical analysis was performed using Kaplan-Meier survival curves, Andersen 95% confidence intervals, approximate confidence intervals for log hazard-ratios, and multivariate Cox proportional hazard models.

Results

The median clinical follow up time was 7.2 months. On multivariate analysis, survival statistically favored patients treated with SRS alone when compared to patients treated with WBRT alone (p < 0.001), patients treated with resection with SRS when compared to patients treated with SRS alone (p = 0.020), patients in ECOG-PS class 0 when compared to patients in ECOG-PS classes 2 (p = 0.04), 3 (p < 0.001), and 4 (p < 0.001), patients in the non-small-cell lung cancer group when compared to patients in the combined melanoma and renal-cell carcinoma group (p < 0.001), and patients with breast cancer when compared to patients with non-small-cell lung cancer (p < 0.001).

Conclusions

In our analysis, patients benefited from a combined modality treatment approach and physicians must consider patient age, performance status, and primary tumor histology when recommending specific treatments regimens.

Incidence, timing, and treatment of new brain metastases after Gamma Knife surgery for limited brain disease: the case for reducing the use of whole-brain radiation therapy

Object

In this paper, the authors' goal was to analyze the incidence, timing, and treatment of new metastases following initial treatment with 20-Gy Gamma Knife surgery (GKS) alone in patients with limited brain metastases without whole-brain radiation therapy (WBRT).

Methods

A retrospective analysis of 114 consecutive adults (75 women and 34 men; median age 61 years) with KPS scores of 60 or higher who received GKS for 1–3 brain metastases ≤ 2 cm was performed (median lesion volume 0.35 cm3). Five patients lacking follow-up data were excluded from analysis. After treatment, patients underwent MR imaging at 6 weeks and every 3 months thereafter. New metastases were preferentially treated with additional GKS. Indications for WBRT included development of numerous metastases, leptomeningeal disease, or diffuse surgical-site recurrence.

Results

The median overall survival from GKS was 13.8 months. Excluding the 3 patients who died before follow-up imaging, 12 patients (11.3%) experienced local failure at a median of 7.4 months. Fifty-three patients (50%) developed new metastases at a median of 5 months. Six (7%) of 86 instances of new lesions were symptomatic. Most patients (67%) with distant failures were successfully treated using salvage GKS alone. Whole-brain radiotherapy was indicated in 20 patients (18.3%). Thirteen patients (11.9%) died of neurological disease.

Conclusions

For patients with limited brain metastases and functional independence, 20-Gy GKS provides excellent disease control and high-functioning survival with minimal morbidity. New metastases developed in almost 50% of patients, but additional GKS was extremely effective in controlling disease. Using our algorithm, fewer than 20% of patients required WBRT, and only 12% died of progressive intracranial disease.

Early significant tumor volume reduction after radiosurgery in brain metastases from renal cell carcinoma results in long-term survival

PURPOSE

To retrospectively evaluate survival of patients with brain metastasis from renal cell carcinoma (RCC) after radiosurgery.

PATIENTS AND METHODS

Between 1998 and 2010, 46 patients were treated with radiosurgery, and the total number of lesions was 99. The mean age was 58.9 years (range, 33-78 years). Twenty-six patients (56.5%) had a single brain metastasis. The mean tumor volume was 3.0 cm(3) (range, 0.01-35.1 cm(3)), and the mean marginal dose prescribed was 20.8 Gy (range, 12-25 Gy) at the 50% isodose line. A patient was classified into the good-response group when the sum of the volume of the brain metastases decreased to less than 75% of the original volume at a 1-month follow-up evaluation using MRI.

RESULTS

As of December 28, 2010, 39 patients (84.8%) had died, and 7 (15.2%) survived. The overall median survival time was 10.0 ± 0.4 months (95% confidence interval, 9.1-10.8). After treatment, local tumor control was achieved in 72 (84.7%) of the 85 tumors assessed using MRI after radiosurgery. The good-response group survived significantly longer than the poor-response group (median survival times of 18.0 and 9.0 months, respectively; p = 0.025). In a multivariate analysis, classification in the good-response group was the only independent prognostic factor for longer survival (p = 0.037; hazard ratio = 0.447; 95% confidence interval, 0.209-0.953).

CONCLUSIONS

Radiosurgery seems to be an effective treatment modality for patients with brain metastases from RCC. The early significant tumor volume reduction observed after radiosurgery seems to result in long-term survival in RCC patients with brain metastases.