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

Brain metastases: An update on the multi-disciplinary approach of clinical management

IMPORTANCE

Brain metastasis (BM) is the most common malignant intracranial neoplasm in adults with over 100,000 new cases annually in the United States and outnumbering primary brain tumors 10:1.

OBSERVATIONS

The incidence of BM in adult cancer patients ranges from 10-40%, and is increasing with improved surveillance, effective systemic therapy, and an aging population. The overall prognosis of cancer patients is largely dependent on the presence or absence of brain metastasis, and therefore, a timely and accurate diagnosis is crucial for improving long-term outcomes, especially in the current era of significantly improved systemic therapy for many common cancers. BM should be suspected in any cancer patient who develops new neurological deficits or behavioral abnormalities. Gadolinium enhanced MRI is the preferred imaging technique and BM must be distinguished from other pathologies. Large, symptomatic lesion(s) in patients with good functional status are best treated with surgery and stereotactic radiosurgery (SRS). Due to neurocognitive side effects and improved overall survival of cancer patients, whole brain radiotherapy (WBRT) is reserved as salvage therapy for patients with multiple lesions or as palliation. Newer approaches including multi-lesion stereotactic surgery, targeted therapy, and immunotherapy are also being investigated to improve outcomes while preserving quality of life.

CONCLUSION

With the significant advancements in the systemic treatment for cancer patients, addressing BM effectively is critical for overall survival. In addition to patient's performance status, therapeutic approach should be based on the type of primary tumor and associated molecular profile as well as the size, number, and location of metastatic lesion(s).

Stereotactic radiosurgery for melanoma brain metastases: dose-size response relationship in the era of immunotherapy

PURPOSE/OBJECTIVE(S)

To determine, for intact melanoma brain metastases (MBM) treated with single-fraction stereotactic radiosurgery (SRS), whether planning parameter peripheral dose per lesion diameter (PDLDm, Gy/mm) and lesion control (LC) differs with versus without immunotherapy (IO).

MATERIALS/METHODS

We performed a retrospective analysis of patients with intact MBM treated with SRS from 2008 to 2019. Cox-frailty models were constructed to include confounders selected by penalized Cox regression models with a LASSO selector. Interaction effect testing was used to determine whether a significant effect between IO and PDLDm could be demonstrated with respect to LC.

RESULTS

The study cohort comprised 67 patients with 244 MBMs treated with SRS (30 patients with 122 lesions treated with both SRS and IO) were included. The logarithm of PDLDm was selected as a predictor of LC (HR 0.307, 95% CI 0.098-0.441), adjusting for IO receipt (HR 0.363, 95% CI 0.108-1.224). Interaction effect testing demonstrated a differential effect of PDLDm by IO receipt, with respect to LC (p = 0.048). Twelve-month LC rates for a 7.5 mm lesion receiving SRS (18 Gy) with IO versus without IO were 87.8% (95% CI 69.0-98.3%) versus 79.8% (95% CI 55.1-93.8%) respectively.

CONCLUSION

PDLDm predicted LC in patients with small MBMs treated with single-fraction SRS. We found a differential effect of dose per lesion size and LC by immunotherapy receipt. Future studies are needed to determine whether lower doses of single-fraction SRS afford similarly effective LC for patients with small MBMs receiving immunotherapy.

Hypofractionated Radiation Therapy for Large Brain Metastases

Single fraction radiosurgery (SRS) treatment is an effective and recognized alternative to whole brain radiation for brain metastasis. However, SRS is not always possible, especially in tumors of a larger diameter where the administration of high dose in a single fraction is limited by the possibility of acute and late side effects and the dose to the surrounding organs at risk. Hypofractionated radiation therapy allows the delivery of high doses of radiation per fraction while minimizing adverse events, all the while maintaining good local control of lesions. The optimal dose fractionation has however not been established. This overwiew presents available evidence and rationale supporting usage of hypofractionated radiation therapy in the treatment of large brain metastases.

Characteristics and treatments of large cystic brain metastasis: radiosurgery and stereotactic aspiration

Brain metastasis represents one of the most common causes of intracranial tumors in adults, and the incidence of brain metastasis continues to rise due to the increasing survival of cancer patients. Yet, the development of cystic brain metastasis remains a relatively rare occurrence. In this review, we describe the characteristics of cystic brain metastasis and evaluate the combined use of stereotactic aspiration and radiosurgery in treating large cystic brain metastasis. The results of several studies show that stereotactic radiosurgery produces comparable local tumor control and survival rates as other surgery protocols. When the size of the tumor interferes with radiosurgery, stereotactic aspiration of the metastasis should be considered to reduce the target volume as well as decreasing the chance of radiation induced necrosis and providing symptomatic relief from mass effect. The combined use of stereotactic aspiration and radiosurgery has strong implications in improving patient outcomes.

Brain metastases of breast cancer

Brain metastases of breast cancer remain a difficult problem for clinical management. Their incidence appears to be increasing, which is likely due to longer survival times for advanced breast cancer patients as well as additional and improved tools for detection. Molecular features of tumors associated with this syndrome are not yet understood. In general, survival may be improving for brain metastases due to better local control in the CNS, as well as improvements in systemic disease management. Selected patients with brain metastases are able to undergo surgical resection, which has been associated with extended disease control in some patients. However, whole-brain radiation has been the mainstay for treatment for most patients. Stereotactic radiosurgery is playing an increasing role in the primary treatment of brain metastases, as well as for salvage after whole-brain radiation. Recent series have reported median survivals of 13 months or longer with stereotactic radiosurgery. Further improvements in radiation-based approaches may come from ongoing studies of radiosensitizing agents. The ability of systemic treatments to impact brain metastases has been debated, and specific treatment regimens have yet to be defined. New approaches include chemotherapy combinations, biologic therapies and novel drug-delivery strategies.

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.

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.

Gamma Knife surgery for brain metastases from colorectal cancer. Clinical article

OBJECT

The outcomes after Gamma Knife surgery (GKS) were retrospectively analyzed in patients with brain metastases from radioresistant primary colorectal cancer to evaluate the efficacy of GKS and the prognostic factors for local tumor control and overall survival.

METHODS

The authors reviewed the medical records of 152 patients with 616 tumors. The group included 102 men and 50 women aged 35-85 years (mean age 64.4 years), who underwent GKS for metastatic brain tumors from colorectal cancer between April 1992 and September 2008 at Yokohama Rosai Hospital.

RESULTS

The mean prescription dose to the tumor margin was 18.5 Gy (range 8-30 Gy). The mean tumor volume at GKS was 2.0 cm(3) (range 0.004-10.0 cm(3)). The primary tumors were located in the colon in 88 patients and the rectum in 64. The median interval between the diagnosis of primary lesions and the diagnosis of brain metastases was 27 months (range 0-180 months). The median neuroradiological follow-up period after GKS was 3 months (mean 6.4 months, range 1-93 months). The local tumor growth control rate, based on MR imaging, was 91.2%. The significant factors for unfavorable local tumor growth control, based on multivariate analysis, were larger tumor volume (p = 0.001) and lower margin dose (p = 0.016). The median overall survival time was 6 months. Lower Karnofsky Performance Scale (KPS) score (p = 0.026) and the presence of extracranial metastases (p = 0.004) at first GKS were significantly correlated with poor overall survival period in multivariate analysis. The cause of death was systemic disease in 112 patients and neurological disease in 13 patients. Leptomeningeal carcinomatosis was significantly correlated with a shorter duration of neurological survival in multivariate analysis (p < 0.0001).

CONCLUSIONS

Gamma Knife surgery is effective for suppression of local tumor growth in patients with brain metastases from radioresistant colorectal primary cancer. Therefore, clinical and radiological screening of intracranial metastases for patients with lower KPS scores and/or the presence of extracranial metastases as well as follow-up examinations after GKS for brain metastases should be performed periodically in patients with colorectal cancer, because the neurological prognosis is improved by initial and repeat GKS for newly diagnosed or recurrent tumors leading to a prolonged high-quality survival period.

Improved survival in patients with end-stage cancer treated with coenzyme Q(10) and other antioxidants: a pilot study

This pilot study evaluated the survival of patients with end-stage cancer who received supplements of coenzyme Q(10) and a mixture of other antioxidants (e.g. vitamin C, selenium, folic acid and beta-carotene). During a period of 9 years, 41 patients who had end-stage cancer were included. Forty patients were followed until death and one patient was lost to follow-up and presumed dead. Primary cancers were located in the breast, brain, lungs, kidneys, pancreas, oesophagus, stomach, colon, prostate, ovaries and skin. The median predicted survival time was calculated from Kaplan-Meier curves for each patient at inclusion. Median predicted survival was 12 months (range 3 - 29 months), whereas median actual survival was 17 months (1 - 120 months), which is > 40% longer than the median predicted survival. Mean actual survival was 28.8 months versus 11.9 months for mean predicted survival. Ten patients (24%) survived for less time than predicted, whereas 31 (76%) survived for longer. Treatments were very well tolerated with few adverse effects.

Current Concepts and Controversies in the Treatment of Parenchymal Brain Metastases: Improved Outcomes with Aggressive Management

The multimodality management of brain metastases has undergone significant refinement in the last decade. Although brain metastases remain a significant source of morbidity and mortality for many cancer patients, aggresive management has led to pronounced gains in neurological functioning, disease free survival and overall survival compared to standard treatment regimens consisting of only whole brain radiation therapy. Representative studies reviewing the role of aggressive management approaches including surgical resection with or without whole brain radiation therapy or non-surgical approaches employing stereotactic radiosurgery alone or in combination with whole brain radiation therapy are highlighted. Additionally, the emerging role of systemic agents showing distinct clinical activity in patients with brain metastases are also discussed. As we continue to gain advances in systemic therapies for metastatic disease, local control of brain metastases in these patients is likely to become more critical in improving survival and quality of life, thereby calling for a more aggressive multi-modal approach to this population of patients.

Evaluation of different score index for predicting prognosis in gamma knife radiosurgical treatment for brain metastasis

PURPOSE

To assess the utility of the Radiation Therapy Oncology Group Recursive Partitioning Analysis (RPA) and Score Index for Radiosurgery (SIR) stratification systems in predicting survival in patients with brain metastasis treated with Gamma Knife radiosurgery (GKRS).

METHODS AND MATERIALS

A total of 185 patients were included in the study. Patients were stratified according to RPA and SIR classes. The RPA and SIR classes, age, Karnofsky Performance Status (KPS), and systemic disease were correlated with survival.

RESULTS

Five patients were lost to follow-up. Median survival in patients in RPA Class 1 (30 patients) was 17 months; in Class 2 (140 patients), 10 months; and in Class 3 (10 patients), 3 months. Median survival in patients in SIR Class 1 (30 patients) was 3 months; in Class 2 (135 patients), 8 months; and in Class 3 (15 patients), 20 months. In univariate testing, age younger than 65 years (p = 0.0004), KPS higher than 70 (p = 0.0001), RPA class (p = 0.0078), SIR class (p = 0.0002), and control of the primary tumor (p = 0.02) were significantly associated with improved outcome. In multivariate analysis, KPS (p < 0.0001), SIR class (p = 0.0008), and RPA class (p = 0.03) had statistical value.

CONCLUSIONS

This study supports the use of GKRS as a single-treatment modality in this selected group of patients. Stratification systems are useful in the estimation of patient eligibility for GKRS. A second-line treatment was necessary in 30% of patients to achieve distal or local brain control. This strategy is useful to control brain metastasis in long-surviving patients.

Stereotactic drainage and Gamma Knife radiosurgery of cystic brain metastasis

OBJECT

Treatment options for patients with brain metastasis include tumor resection, whole-brain radiation therapy, and radiosurgery. A single treatment is not useful in cases of multiple tumors, of which at least 1 is a cystic tumor. The purpose of this study was to assess the role of stereotactic drainage and Gamma Knife surgery (GKS) in the treatment of cystic brain metastasis.

METHODS

Between January 2001 and November 2005, 680 consecutive patients with brain metastases underwent GKS at our hospital, 30 of whom were included in this study (18 males and 12 females, mean age 60.6 +/- 11 years, range 38-75 years). Inclusion criteria were: 1) no prior whole-brain radiation therapy or resection procedure; 2) a maximum of 4 lesions on preoperative MR imaging; 3) at least 1 cystic lesion; 4) a Karnofsky Performance Scale score >or= 70; and 5) histological diagnosis of a malignant tumor.

RESULTS

Non-small cell lung carcinoma was the primary cancer in most patients (19 patients [63.3%]). A single metastasis was present in 13 patients (43.3%). There was a total of 81 tumors, 33 of which were cystic. Ten patients (33.3%) were in recursive partitioning analysis Class I, and 20 (66.6%) were in Class II. Before drainage the mean tumor volume was 21.8 ml (range 3.8-68 ml); before GKS the mean tumor volume was 10.1 ml (range 1.2-32 ml). The mean prescription dose to the tumor margin was 19.5 Gy (range 12-25 Gy). Overall median patient survival was 15 months. The 1- and 2-year survival rates were 54.7% (95% confidence interval 45.3-64.1%) and 34.2% (95% confidence interval 23.1-45.3%). Local tumor control was achieved in 91.3% of the patients.

CONCLUSIONS

The results of this study support the use of a multiple stereotactic approach in cases of multiple and cystic brain metastasis.

Prognostic factors for survival after stereotactic radiosurgery vary with the number of cerebral metastases

BACKGROUND

Little is understood about the factors that influence survival in patients who undergo gamma-knife stereotactic radiosurgery (SRS) for brain metastases.

METHODS

Demographic, disease, treatment, and survival data on 334 patients with intracranial metastases who underwent initial SRS from 1998 to 2004 were abstracted from treatment records and from the Connecticut Tumor Registry. Multivariate survival analysis was used to identify factors that independently affected survival.

RESULTS

The median age of the patient population was 57.3 years. The median number of lesions treated in a single session was 2 (range, 1-36 lesions treated). The most common tumor histologies were nonsmall cell lung carcinoma (36%), breast cancer (16%), and melanoma (16%). Three hundred patients (90%) had confirmed deaths; the median survival after SRS was 8.1 months. Survival was significantly better in patients who had from 1 to 3 metastases (median, 8.5 months) compared with patients who had > or =4 metastases (median, 6.3 months; hazard ratio [HR], 0.65; P = .003). In the subgroup of patients who had from 1 to 3 metastases, systemic control (HR, 0.49; P < .001), breast cancer (HR, 0.57; P = .003), and total tumor volume < 5 cc (HR, 0.65; P = .002) were associated independently with increased survival, and esophageal cancer (HR, 2.36; P = .042) was associated with decreased survival. In the subgroup of patients who had > or =4 metastases, only age <45 years was associated independently with increased survival (HR, 0.39; P = .006); and melanoma (HR, 2.32; P = .008) and the receipt chemotherapy (HR, 2.59; P = .077) were associated with decreased survival. Sex, race, metastases location, whole-brain radiation, and cranial surgery had no independent associations with altered survival.

CONCLUSIONS

The data from this study suggested that different factors affected survival in patients who had from 1 to 3 metastases and patients who had > or =4 metastases. Further research into this area may clarify causes for this discrepancy and improve prognostication.

Integration of gamma knife surgery in the management of cerebral metastases from melanoma

The aim of this study was to investigate the effect of gamma knife surgery on the local control of cerebral metastases from melanoma and to assess survival. In 29 patients, 105 of 178 cerebral metastases were treated with gamma knife surgery. Only five patients had metastases confined to the brain. Of the 96 metastases with magnetic resonance imaging follow-up, 61.5% regressed by more than 50% of the pretreatment volume, 25% regressing by more than 90% and 13.5% completely. The median survival from gamma knife surgery was 5.7 months (longest survival, 38 months). In multivariate analyses, a larger number of lesions requiring treatment (P < 0.001), recursive partitioning analysis class (P = 0.009) and a long time interval from initial melanoma diagnosis to detection of cerebral metastases (P = 0.001) influenced survival. It can be concluded that gamma knife surgery is a useful adjunct in the management of cerebral metastases from melanoma and has a significant impact on local control. Its greatest potential may be achieved in conjunction with systemic chemotherapy, especially in the presence of extracerebral metastases.

Stereotactic radiosurgery for patients with solid brain metastases: current status

The goal of this article is to provide a contemporary update on the use of stereotactic radiosurgery (SRS) for the treatment of intracranial metastatic disease. We discuss the rationale for employing SRS in brain metastases and describe the critical factors that predict outcome. We highlight the main clinical indications for SRS including treatment of recurrent brain metastases after previous whole brain radiation therapy (WBRT), as a boost after WBRT, and as sole therapy for newly diagnosed tumors. For each clinical scenario, we offer a treatment algorithm based on our clinical experience. The article also addresses the most common complications associated with SRS and their treatment.

Is early recognition of radiologically silent brain metastasis from breast cancer beneficial? A retrospective study of 22 cases

Over a period of 10 years, twenty-two patients with T2-3N2Mx breast cancer presented with symptoms of increased intracranial pressure (ICP), but brain CT scan and/or MRI did not reveal any signs of a space occupying lesion. A brain CT scan and an MRI study were performed every 15 days. Ten patients refused this close follow up. Thus, two groups were formed group A (n = 12) included the patients who were close's followed and group B (n = 10) consisted of those patients who were not. Therefore, Group A, being under careful follow-up, initiated radiotherapy were quickly. The median time from the presentation of increased ICP symptoms until the appearance of metastases on CT and/or MRI directly followed by brain irradiation was 48 days (SE = 6.1) for group A and 72 days (SE = 0.7) for group B (p = 0.0085, log-rank test). In group A, median Overall Survival (OS) was 171.0 (SE = 21.5) days, and was 99.0 (SE = 6.3) days (p = 0.014) for group B. Volumetric analysis of the secondary brain lesions at the initiation of radiotherapy showed a total volume of metastatic lesions of 19.5 +/- 13.9 cm3 versus 65.3 +/- 20.7 cm3 for groups A and B, respectively (p < 0.001, Mann-Whitney test). Post-radiotherapy, Karnofsky Performance Status and Visual Analogue Score were also improved for group A versus B (p = 0.002). Group A appeared to benefit from close follow-up since the metastases were detected and irradiation was given sooner compared with group B, thus achieving better performance status and prolonged survival. Radiologically silent brain metastases from breast cancer should not be ignored because timely whole brain irradiation should be the goal of clinicians. Clinical suspicion should lead to close follow-up with multiple CT/MRI studies and cerebral spinal fluid cytology until the final diagnosis.

Stereotactic radiosurgery for brain metastases from gastrointestinal tract cancer

BACKGROUND

Outcomes in patients with brain metastases from gastrointestinal tract cancers are not well defined. In this study we used precise, single-session, focal tumor irradiation (radiosurgery) in patients with brain metastases and evaluated the results.

METHODS

Thirty-nine patients had brain metastases from gastrointestinal tract cancer and were treated with radiosurgery. Thirty-two also had whole brain radiotherapy. Primary lesions included colorectal cancer (n = 25), esophageal cancer (n = 11), cholangiocarcinoma (n = 1), duodenal cancer (n = 1), and jejunal cancer (n = 1). Seventy-two tumors were treated.

RESULTS

The overall median survival was 9 months after diagnosis of metastatic brain disease and 5 months after radiosurgery. The 1-year survival rate after radiosurgery was 19%. The last imaging study of 49 tumors showed complete remission (CR) in 3 tumors (6.1%), partial remission (PR) in 27 tumors (55.1%), no change (NC) in 11 tumors (22.4%), and progression in 8 tumors (16.3%). The local tumor control rate (CR, PR, NC) was 84%. Two patients (5.1%) had a new or worsening neurologic deficit after radiosurgery.

CONCLUSIONS

Stereotactic radiosurgery provides reasonable local control of brain metastases from gastrointestinal tract cancer with few side effects. However, it should be used judiciously in patients with active extracranial cancers since the expected survival may be limited.

Radiosurgery and radiotherapy for non-small-cell lung cancer metastatic to brain

Non-small-cell lung cancer metastatic to brain represents a common problem in oncology. Treatment modalities include stereotactic radiosurgery (SRS), whole-brain radiotherapy (WBRT), surgical resection, supportive care, or a combination of these options. This review outlines therapeutic strategies for treatment with particular attention to the use of SRS. Radiosurgical technique, radiobiology, dose prescription, patient selection, and results of therapy are discussed. The term SRS describes a radiation procedure that utilizes a three-dimensional stereotactic localization system to precisely treat small intracranial targets with a single, large, highly focal radiation dose. Stereotactic radiosurgery is appealing for several reasons; it is minimally invasive, easily tolerated, and highly effective, and patients return to normal baseline function within 24 hours. Stereotactic radiosurgery provides much higher control rates of treated lesions than does WBRT. Randomized trials are underway to ascertain the optimal role and timing of SRS in relation to WBRT in order to maximize control, survival, quality of life, and neuropsychological outcome.

Gamma knife radiosurgery for patients with multiple cerebral metastases

Although efficacy of gamma knife radiosurgery has been demonstrated in numerous studies, the policies in patients with multiple metastases seem to be unequivocal. The maintained quality of life, the possibility of short hospitalization and the continuation of a systemic chemotherapy are increasingly important arguments in favor of a minimally invasive radiosurgical approach. These factors are particularly emphasized in patients with a dismal prognosis. The current retrospective analysis was undertaken to summarize the clinical results of radiosurgery in patients with multiple cerebral metastases of various primary cancer. Fractionated whole brain radiotherapy (WBRT) was omitted as prophylactic treatment and applied only in cases with general tumor spread. Clinical data of all consecutive patients (n = 215) who received gamma knife radiosurgery for cerebral metastases between January 2001 and January 2003 at the gamma knife Centers of the Karolinska Hospital and H.M. Queen Sophia Hospital (Sophiahemmet) Stockholm were analyzed retrospectively. 172 patients were treated for multiple metastases (198 treatments). The median prescription dose was 22 Gy (range 14-34 Gy). The Kaplan Meier plot shows a median survival (MST) of 7.8 months for patients with multiple cerebral metastases and 13.7 months for patients with single metastases. There was no relation between survival and number of metastases in patients with multiple metastases. Within this group 11.6% (20/172 patients) developed adverse radiation reactions. Tumor recurrences were documented by FDG-PET in 7 patients (out of 172 patients: 4.1%) after a median latency of 10 months after radiosurgery. In summary, gamma knife radiosurgery provides a highly effective and minimally invasive method to treat patients with multiple cerebral metastases even without prophylactic WBRT. Local control and patient survival in the present series of patients is in accordance with other retrospective series of patients with single and multiple metastases.

Surgical treatment of malignant melanoma

The surgical management of melanoma has evolved over the last 100 years. when early concepts of lymphatic permeation of the tumors and metastases led surgeons to perform radical operative procedures. Wide excision of primary melanoma is now performed with 1- to 2-cm radial margins, significantly reducing the need for complex plastic closures, skin grafts. and hospital admissions. Although elective lymph node dissection remains controversial as a therapeutic procedure, the development of SL has improved the staging of the regional lymph nodes and diminished the morbidity of lymph node dissection. The role of SL for routine care of melanoma patients remains unknown. Metastasectomy, which is the surgical resection of distant metastases with tumor-free surgical margins, has not been popular for AJCC stage IV patients with multiple metastases, because surgery is considered a local therapy and therefore of little value for management of disseminated disease. Nevertheless, the many reports of long-term survival after resection of distant melanoma metastases to diverse soft tissue and organ sites clearly indicate that this form of cytoreductive surgery can be extremely successful in carefully selected patients. Unlike chemotherapy, complete surgical metastasectomy can rapidly render a patient disease-free with only a short period of postoperative morbidity. Most patients fully recover from the surgical procedure within 6 weeks, returning to most or all activities. The ability to select patients for surgery is based on the development of more sophisticated imaging techniques, which allow better preoperative differentiation of patients with single versus multiple metastases and improve the surgeon's ability to identify and resect multiple metastatic sites. The overall data suggest that patients whose metastases can be completely resected will experience improved overall survival and occasional long-term cure regardless of the metastatic organ site and number of metastases. We believe that increased understanding of the biology of the primary and metastases, dramatic improvement in the accuracy of staging metastatic disease, and better techniques of surgical resection provide the best chance for long-term palliation or cure of melanoma. Cytoreductive surgery should be considered a form of immunotherapy. The long-term clinical benefit of this therapy depends on the patient's immune response to, the surgical reduction in tumor burden: an immune response that controls subclinical micrometastases should optimize postoperative survival.

Properly selected patients with multiple brain metastases may benefit from aggressive treatment of their intracranial disease

To determine whether properly selected patients with multiple brain metastases benefit from aggressive treatment of their intracranial disease, we reviewed 52 patients having stereotactic radiosurgery (SRS), tumor resection, or both between April 1997 and March 2000. Tumor histology included lung (n = 18, 35%), breast (n = 11, 21%), renal (n = 6, 12%), melanoma (n = 6, 12%), and other (n = 11, 21%). The median patient age was 58 years, the median Karnofsky performance status (KPS) was 90, and the median number of tumors was three. Twenty patients (39%) had progressed after prior radiation therapy. Treatment included multiple craniotomies and tumor resection (n = 5, 10%), radiosurgery (n = 31, 60%), or resection and radiosurgery (n= 16, 30%). Median survival was 15.5 months. The one- and two-year actuarial survivals were 63% and 27%, respectively. Multivariate analysis found radiation therapy oncology group recursive partitioning analysis (RTOG RPA) Class (1 vs. 2/3) correlated with improved survival (Relative risk = 2.60, 95% CI 1.13-5.97, p = 0.03). Class 1 patients (KPS > or = 70, age < 65 years, and controlled primary with no extracranial metastases) survived a median of 19 months whereas Class 3 patients (KPS < 70) survived 8 months. Class 2 patients (all other patients) survived a median of 13 months. Thirty-five patients (67%) had intracranial progression at a median of 8.0 months. Intracranial progression was local (n = 6), distant (n = 23), or local and distant (n = 6); 26 patients with intracranial progression underwent additional brain tumor treatments. Multivariate analysis found patients with radiosensitive tumors (lung, breast, other) had fewer intracranial recurrences compared to patients with radio-resistant tumors (melanoma, renal, sarcoma) (Relative risk = 2.43, 95% CI 1.13-5.10, p = 0.02). The length of survival in our series is quite comparable to historical reports on the management of brain metastasis patients, and supports aggressive intervention for RTOG RPA Class 1 patients and Class 2 patients with controlled primary disease who have a limited number of brain metastases.

The treatment of brain metastases from malignant melanoma

Metastasis to the CNS develops in nearly half of patients with advanced melanoma; in 15% to 20% of these patients, the CNS is the first site of relapse. While systemic therapy for metastatic melanoma produces objective responses in 15% to 50% of patients, the available drugs do not penetrate well into the CNS, and these patients rarely benefit from systemic therapy. Although brain metastasis may be treated with surgery and/or stereotactic radiosurgery (SRS) when disease is limited to approximately one to three lesions, treatment for patients with large or multiple metastases is limited to whole brain irradiation (WBRT). While formal response and survival analyses of the impact of WBRT in melanoma have not been reported, the estimated median survival time for unselected patients with CNS metastases is only 2 to 4 months, with 1-year survival rates of less than 13%. In a selected population of patients with limited CNS involvement, surgical resection alone or in combination with WBRT appears to prolong median survival. More recently, SRS has been shown to be an effective local treatment for selected patients with brain metastases. In several retrospective reports of patients with melanoma CNS metastases, treatment with surgical resection alone or in combination with WBRT has been demonstrated to prolong median survival. More recently, SRS has been shown to be an effective local treatment for selected patients with brain metastases. In several retrospective reports, patients with CNS metastases from melanoma treated with a combination of WBRT plus SRS or SRS alone had median survivals and rates of control in the CNS superior to published reports for traditional WBRT. Most of these patients died from progressive extracranial disease with locally controlled CNS disease. Investigation of the contribution of newer systemic agents to the control of melanoma metastatic to the CNS has been based on the identification of drugs that have antitumor activity and the ability to cross the blood-brain barrier. Fotemustine is a nitrosourea that produced similar activity in CNS metastasis as in systemic disease, with a response rate of about 25%. Temozolomide (TMZ) is an oral alkylating agent that acts via the same mechanism as dacarbazine (DTIC), the most active single agent in melanoma. TMZ, which is highly active in brain tumors, has also been associated with activity in systemic and CNS metastases in melanoma patients, also in the 25% range. Efforts are underway to assess the additive benefit of TMZ and other drugs to WBRT or focused radiotherapy in this disease.

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.

Brain metastases in melanoma: a European perspective

CNS involvement is a common feature of metastatic melanoma. Despite this, there is little evidence upon which clinicians can base decisions about treatment. The short prognosis and significant symptoms usually associated with melanoma brain metastases have excluded these patients from clinical trials. In Europe the standard treatment involves whole brain radiotherapy, although selected centers offer other modalities, including surgery, radiosurgery, and chemotherapy.

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.

Radiosurgery for brain metastases: who may not benefit?

PURPOSE

To select a group of patients with brain metastases for whom stereotactic radiosurgery (SRS) may not be beneficial.

PATIENTS, MATERIALS, AND METHODS

Actuarial survival of 87 patients with brain metastases treated with SRS between July 1993 and May 1999 was retrospectively analyzed under stratification by the Score Index for Stereotactic Radiosurgery for Brain Metastases (SIR). To identify the group of patients most likely to survive less than 6 months after SRS, Cox model survival curves were calculated for all SIR values, and Kaplan-Meier survival curves were calculated for two SIR subsets (0-5 and 6-10) and were compared by log-rank test.

RESULTS

Overall median survival after SRS was 6.88 months. The stratification of patients into two SIR subsets (0-5 and 6-10) sustained statistical significance regarding survival with p = 0.0001. The median survival time for the group of patients with SIR between 0 and 5 was 4.52 months (95% confidence interval of 2.82 to 5.84 months). Survival probability at 6 months for this group of patients with poor prognosis was 35.6%.

CONCLUSION

Patients with brain metastases and SIR of 5 or lower have an expected median survival of less than 6 months after treatment with radiosurgery. Thus, radiosurgery may not be beneficial for this group of patients.

Stereotactic radiosurgery for brain tumors

In the 50 years since Leksell developed the concepts and initial hardware for modern brain radiosurgery, the treatment has progressed to the point where it is used commonly for arteriovenous malformations, benign masses, and metastases. Radiosurgery offers patients an effective treatment of life-threatening lesions with a reasonably low risk for discomfort and injury. In the 1990s, the procedure was used widely as primary and adjuvant treatment. The difficulty of defining the boundaries of primary brain cancers makes determining treatment targets problematic. Better imaging and computing offer a bright future for the technology.

Advances in stereotactic radiosurgery for brain neoplasms

It has been nearly half a century since Leksell introduced brain radiosurgery. In the past decade, the procedure has become widely used as both a primary and adjuvant treatment. Radiosurgery is now commonly employed for arteriovenous malformations, brain metastases, and several benign lesions. Its use in primary brain malignancy remains of uncertain benefit. Improvements in imaging, hardware, and software promise an even greater role for the technique.

Multiple cysts in the cerebral white matter: a rare complication of whole brain radiation therapy

We describe a patient with multiple cysts in the cerebral white matter, several years after whole brain radiation therapy (WBRT) for a solitary cerebellar metastasis of a lung carcinoma. MR images of the brain show diffuse white matter changes, 1 year after radiation, and cyst formation in the white matter, starting 3.5 years later. We conclude that cysts in the cerebral white matter can be a late stage of white matter damage after whole brain radiation therapy in long-term survivors with brain metastases.

Gamma knife radiosurgery for brain metastases: prognostic factors for survival and local control

Object. The authors conducted an analysis of prognostic factors for patient survival and local control of brain metastases after gamma knife radiosurgery.

Methods. In the survival analysis, 53 consecutive patients with 121 lesions treated in the last 2 years were examined. Common primary sites were lung (26 patients), kidney (seven), breast (three), and colon (three). Patient age ranged from 28 to 75 years (median 58 years) and the female/male ratio was 1:0.9. The median tumor volume was 2.1 cm3 (range 0.02–45.5cm3) and the average prescription dose was 15.4 Gy to the 50% isodose. The median follow up was 12 months (range 1–23 months) and the median survival was 46 weeks.

Six-month and 1-year survival rates were 63% and 39%, respectively. Karnofsky Performance Scale score, tumor volume, and presence of extracranial disease were statistically significant prognostic factors (p < 0.05) for survival in multivariate analysis. Number of lesions, patient age, and adjuvant whole-brain radiation therapy were not statistically significant. Ninety-one of 121 lesions with follow-up images were included in the local control analysis. The 1-year actuarial local control rate was 48%. In multivariate analysis smaller volume was associated with better control (p = 0.0043), and, control period of renal cell carcinoma was shorter than that of the other tumor types (p = 0.0070).

Conclusions. Karnofsky Performance Scale score, tumor volume, controlled primary cancer, and absence of extracranial metastases were associated with longer survival in the present study. For local control, tumor volume was a statistically significant factor.

Stereotactic radiosurgery in patients with multiple brain metastases

Object

Patients with multiple brain metastases are often treated primarily with fractionated whole-brain radiation therapy (WBRT). In previous reports the authors have shown that patients with four or fewer brain metastases can benefit from stereotactic radiosurgery in addition to fractionated WBRT. In this paper the authors review their experience using linear accelerator stereotactic radiosurgery to treat patients with multiple brain metastases.

Methods

Fifty-three patients with 149 brain metastases underwent stereotactic radiosurgery. The mean age of patients was 53.1 years (range 20–78 years). There were 23 men and 30 women. The primary tumor location was lung (27 patients), melanoma (10), breast (six), ovary (six), and other (four). All patients harbored at least two metastatic tumors treated with radiosurgery; 27 patients (51%) harbored two lesions, 17 (32%) three lesions, eight (15%) four lesions, and one patient (2%) harbored five lesions. The mean radiation dose administered was 19.6 Gy (range 14–30 Gy), and the mean secondary collimator size was 15.7 mm (range 7.5–40 mm). One hundred thirty-two (89%) of the 149 treated tumors were available for review on magnetic resonance (MR) imaging at 3 months posttreatment. Fifty-two percent were smaller in size, 31% were stable, 9% had increased in size, and 8% had disappeared. New metastatic tumors appeared in 12 (23%) of the 53 patients on MR imaging within 6 months posttreatment. Radiation-induced necrosis occurred at the site of eight (5.4%) of the 149 tumors at 6 months. Seven tumors (4.7%) subsequently required surgical resection for either tumor progression (four cases) or worsening edema from radiation-induced necrosis (three cases). Median actuarial survival was 9.6 months.

Conclusions

Stereotactic radiosurgery can be used to treat patients with up to four brain metastases with a 91% rate of either decrease or stabilization in tumor size and a low rate of radiation-induced necrosis. In the authors' study only a small number of patients subsequently required surgical resection of a treated lesion.

Current treatment of patients with multiple brain metastases

The management of patients with multiple brain metastases remains a difficult challenge for neurosurgeons. This patient population has a poor prognosis when compared with those harboring a solitary brain metastasis, and historically treatment has generally consisted of administering whole-brain radiotherapy once the diagnosis of multiple brain metastases is made. Resection can be useful in a subset of patients with multiple metastases in whom one or two of the lesions are symptomatic, as this may provide rapid reduction of mass effect and edema. Furthermore, the authors of recent studies have shown that stereotactic radiosurgery can be used in certain patients with multiple brain metastases as part of the treatment regimen. In this review the authors outline the treatment options and indications as well as a management strategy for the treatment of patients with multiple brain metastases.

The role of radiosurgery for multiple brain metastases

Object

The authors evaluated the role of stereotactic radiosurgery (SRS) in patients with multiple brain metastases by analyzing prognostic factors that predict survival.

Methods

Between March 1991 and January 1999, 83 patients with multiple brain metastases underwent SRS in which they used a 6 mV linear accelerator. The median radiation dose of 15 Gy (range 6–50 Gy) was delivered to the 40 to 90% (median 87%) isodose line encompassing the target. Actuarial overall survival was calculated from the date of SRS by using the Kaplan–Meier method. Univariate comparisons of survival between different groups were performed using a log-rank test. All 83 patients were included in the calculation of overall survival. Actuarial overall survival was 22% at 1 year and 13% at 2 years, and a median survival of 5.4 months (range, 0.3–28.8 months) was demonstrated. Variables that predicted survival were Karnofsky Performance Scale (KPS) score, extracranial disease status, and the number of intracranial metastases. Median survival in patients with a KPS score greater than as compared with less than 70 was 9.1 and 2.7 months, respectively (p = 0.002). Median survival when comparing absence and presence of extracranial disease was 9.9 and 4.1 months, respectively (p = 0.02). Median survival in patients harboring two, three, or four or more lesions was 6.6 months, 5.4 months, and 2.7 months, respectively (p = 0.02). In patients with a KPS score greater than or equal to 70 and with three or fewer lesions, median survival was 7 months or longer. In patients with four or more lesions median survival was 7.4 months for those with no extracranial disease and 2.4 months for those with extracranial disease. Other variables tested (sex, histological tumor type, previous resection, location of metastases, treatment modality, and tumor status) did not influence outcome.

Conclusions

The absence of extracranial disease, a KPS score greater than or equal to 70, and fewer number of metastases were shown to be significant predictors of longer survival. Stereotactic radiosurgery appears to be a reasonable therapeutic option in patients with up to three lesions when their KPS score is greater than or equal to 70, regardless of extracranial disease status. In those with four or more metastases, however, SRS should be limited to those with no extracranial disease.