Stereotactic radiosurgery for the definitive, noninvasive treatment of brain metastases

Long-term survival in patients with non-small cell lung cancer and synchronous brain metastasis treated with whole-brain radiotherapy and thoracic chemoradiation

BACKGROUND

Brain metastases occur in 30-50% of Non-small cell lung cancer (NSCLC) patients and confer a worse prognosis and quality of life. These patients are usually treated with Whole-brain radiotherapy (WBRT) followed by systemic therapy. Few studies have evaluated the role of chemoradiotherapy to the primary tumor after WBRT as definitive treatment in the management of these patients.

METHODS

We reviewed the outcome of 30 patients with primary NSCLC and brain metastasis at diagnosis without evidence of other metastatic sites. Patients were treated with WBRT and after induction chemotherapy with paclitaxel and cisplatin for two cycles. In the absence of progression, concurrent chemoradiotherapy for the primary tumor with weekly paclitaxel and carboplatin was indicated, with a total effective dose of 60 Gy. If disease progression was ruled out, four chemotherapy cycles followed.

RESULTS

Median Progression-free survival (PFS) and Overall survival (OS) were 8.43 ± 1.5 and 31.8 ± 15.8 months, respectively. PFS was 39.5% at 1 year and 24.7% at 2 years. The 1- and 2-year OS rates were 71.1 and 60.2%, respectively. Three-year OS was significantly superior for patients with N0-N1 stage disease vs. N2-N3 (60 vs. 24%, respectively; Response rate [RR], 0.03; p= 0.038).

CONCLUSIONS

Patients with NSCLC and brain metastasis might benefit from treatment with WBRT and concurrent thoracic chemoradiotherapy. The subgroup of N0-N1 patients appears to achieve the greatest benefit. The result of this study warrants a prospective trial to confirm the benefit of this treatment.

Gamma knife radiosurgery for brainstem metastasis

OBJECTIVE

Brainstem metastases are rarely operable and generally unresponsive to conventional radiation therapy or chemotherapy. Recently, Gamma Knife Radiosurgery (GKRS) was used as feasible treatment option for brainstem metastasis. The present study evaluated our experience of brainstem metastasis which was treated with GKRS.

METHODS

Between November 1992 and June 2010, 32 patients (23 men and 9 women, mean age 56.1 years, range 39-73) were treated with GKRS for brainstem metastases. There were metastatic lesions in pons in 23, the midbrain in 6, and the medulla oblongata in 3 patients, respectively. The primary tumor site was lung in 21, breast in 3, kidney in 2 and other locations in 6 patients. The mean tumor volume was 1,517 mm(3) (range, 9-6,000), and the mean marginal dose was 15.9 Gy (range, 6-23). Magnetic Resonance Imaging (MRI) was obtained every 2-3 months following GKRS. Follow-up MRI was possible in 24 patients at a mean follow-up duration of 12.0 months (range, 1-45). Kaplan-Meier survival analysis was used to evaluate the prognostic factors.

RESULTS

Follow-up MRI showed tumor disappearance in 6, tumor shrinkage in 14, no change in tumor size in 1, and tumor growth in 3 patients, which translated into a local tumor control rate of 87.5% (21 of 24 tumors). The mean progression free survival was 12.2 months (range, 2-45) after GKRS. Nine patients were alive at the completion of the study, and the overall mean survival time after GKRS was 7.7 months (range, 1-22). One patient with metastatic melanoma experienced intratumoral hemorrhage during the follow-up period. Survival was found to be associated with score of more than 70 on Karnofsky performance status and low recursive partitioning analysis class (class 1 or 2), in terms of favorable prognostic factors.

CONCLUSION

GKRS was found to be safe and effective for management of brainstem metastasis. The integral clinical status of patient seems to be important in determining the overall survival time.

The role of surgery, radiosurgery and whole brain radiation therapy in the management of patients with metastatic brain tumors

Brain tumors constitute the most common intracranial tumor. Management of brain metastases has become increasingly complex as patients with brain metastases are living longer and more treatment options develop. The goal of this paper is to review the role of stereotactic radiosurgery (SRS), whole brain radiation therapy (WBRT), and surgery, in isolation and in combination, in the contemporary treatment of brain metastases. Surgery and SRS both offer management options that may help to optimize therapy in selected patients. WBRT is another option but can lead to late toxicity and suboptimal local control in longer term survivors. Improved prognostic indices will be critical for selecting the best therapies. Further prospective trials are necessary to continue to elucidate factors that will help triage patients to the proper brain-directed therapy for their cancer.

Single brain metastases from melanoma: remarks on a series of 84 patients

The authors report on 84 patients with single melanoma brain metastasis surgically treated from 1997 to 2007. There were 46 males and 38 females; mean age was 41 years (range 24-58 years). All patients were surgically treated, and 52 of them received postoperative adjuvant therapy consisting of whole-brain radiation therapy (36), radiosurgery (9), or a combination of these two techniques (7). Brain recurrences were observed in 44 cases, of which 9 were local. Of the latter, seven were re-operated while the remaining two were treated by radiosurgery. At 1-year follow-up, the survival rate was 52% (32 patients) whereas only 12 patients (14%) were still alive after 2 years. None of the patients in which removal was subtotal survived for more than 6 months after surgical treatment. Three years after the onset of the brain metastasis, five patients (6%) were still alive. Survival was significantly influenced by treatment with regard to overall survival reported in other series. A review of literature, together with our own series, suggests that radical surgical treatment of the lesion possibly employing the internal no-touch technique has significantly increased survival in our patients (p < 0.05) and that the association of postoperative radiotherapy and re-operation in the event of recurrent metastatic lesions is advisable even though statistical significance was not reached (p > 0.05).

Cyberknife hypofractionated stereotactic radiosurgery (HSRS) of resection cavity after excision of large cerebral metastasis: efficacy and safety of an 800 cGy × 3 daily fractions regimen

Development of hypofractionated stereotactic radiosurgery (HSRS) has expanded the size of lesion that can be safely treated by focused radiation in a limited number of treatment sessions. However, clinical data regarding the efficacy and morbidity of HSRS in the treatment of cerebral metastasis is lacking. Here, we review our experience with CyberKnife(®) HSRS for this indication. From 2005 to 2010, we identified 37 patients with large (>3 cm in diameter) cerebral metastases resection cavity that was treated with HSRS. This constituted approximately 8% of all treated resection cavities. We reviewed dose regimens, local control, distal control, and treatment associated morbidities. Primary sites for the metastatic lesions included: lung (n = 10), melanoma (n = 12), breast (n = 9), kidney (n = 4), and colon (n = 2). All patients underwent resection of the cerebral metastasis and received 800 cGy × 3 daily fractions to the resection cavity. Of the 37 patients treated, one-year follow-up data was available for 35 patients. The median survival was 5.5 months. Actuarial local control rate at 6 months was 80%. Local failures did not correlate with prior WBRT, or tumor histology. Distant recurrence occurred in 7 of the 35 patients. Morbidities associated with HSRS totaled 9%, including radiation necrosis (n = 1, 2.9%), prolonged steroid use (n = 1, 2.9%), and new-onset seizures (n = 1, 2.9%). This study demonstrates the safety and efficacy of an 800 cGy × 3 daily fractions CyberKnife(®) HSRS regimen for irradiation of large resection cavity. The efficacy compares favorably to historical data derived from patients undergoing WBRT, SRS, or brachytherapy.

Central nervous system metastases in patients with HER2-positive metastatic breast cancer: incidence, treatment, and survival in patients from registHER

PURPOSE

registHER is a prospective, observational study of 1,023 newly diagnosed HER2-positive metastatic breast cancer (MBC) patients.

EXPERIMENTAL DESIGN

Baseline characteristics of patients with and without central nervous system (CNS) metastases were compared; incidence, time to development, treatment, and survival after CNS metastases were assessed. Associations between treatment after CNS metastases and survival were evaluated.

RESULTS

Of the 1,012 patients who had confirmed HER2-positive tumors, 377 (37.3%) had CNS metastases. Compared with patients with no CNS metastases, those with CNS metastases were younger and more likely to have hormone receptor-negative disease and higher disease burden. Median time to CNS progression among patients without CNS disease at initial MBC diagnosis (n = 302) was 13.3 months. Treatment with trastuzumab, chemotherapy, or surgery after CNS diagnosis was each associated with a statistically significant improvement in median overall survival (OS) following diagnosis of CNS disease (unadjusted analysis: trastuzumab vs. no trastuzumab, 17.5 vs. 3.8 months; chemotherapy vs. no chemotherapy, 16.4 vs. 3.7 months; and surgery vs. no surgery, 20.3 vs. 11.3 months). Although treatment with radiotherapy seemed to prolong median OS (13.9 vs. 8.4 months), the difference was not significant (P = 0.134). Results of multivariable proportional hazards analyses confirmed the independent significant effects of trastuzumab and chemotherapy (HR = 0.33, P < 0.001; HR = 0.64, P = 0.002, respectively). The effects of surgery and radiotherapy did not reach statistical significance (P = 0.062 and P = 0.898, respectively).

CONCLUSIONS

For patients with HER2-positive MBC evaluated in registHER, the use of trastuzumab, chemotherapy, and surgery following CNS metastases were each associated with longer survival.

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.

Hypopharyngeal squamous cell carcinoma with hematogenous intracranial metastases: case report

BACKGROUND AND IMPORTANCE

Intracranial metastases are rarely clinically diagnosed in patients with hypopharyngeal squamous cell carcinoma (SCC). In almost all cases, metastatic locations were found at the cavernous sinus and have been considered to develop as perineural invasions.

CLINICAL PRESENTATION

We present a case of hypopharyngeal SCC with distant intracranial metastases through hematogenous spreading. Two cerebral parenchymal metastases from the hypopharyngeal SCC were histologically analyzed in a 49-year-old male patient. The right temporal lesion was diagnosed by craniotomy and treated with radiotherapy. The right occipital lesion was treated with stereotactic radiosurgery (SRS).

CONCLUSION

To the best of our knowledge, there are no reports of hypopharyngeal SCC with cerebral metastases that developed via the hematogenous route. Radiotherapy along with surgery provides better outcomes, and SRS may improve the effect of treatments. Any subclinical neurological deficits should not be neglected, because awareness of this syndrome can lead to earlier diagnosis and alteration in treatment.

Factors related to the local treatment failure of γ knife surgery for metastatic brain tumors

PURPOSE

Radiosurgery (RS) is regarded as a standard therapy for metastatic brain tumors, but local failure requiring repeated therapy for the same lesion remains an unsolved problem. The authors analyzed outcomes of gamma knife surgery (GKS) for metastatic lesions to identify factors of local treatment failure.

MATERIALS AND METHODS

The hospital records of 103 patients with a metastatic brain tumor and monitored for more than 6 months were analyzed. Lesion response to RS was analyzed in 77 patients with available gamma plan data. Local treatment failure was defined as lesion regrowth or repeat GKS within 6 months. In cases with multiple lesions, largest masses were evaluated. Primary sites, metastatic location, Karnofsky scale, tumor size, number of metastatic lesions, and various radiosurgical prescription parameters, namely, Paddick's conformity index (CI), Radiation Therapy Oncology Group (RTOG)-CI, and gradient index, were analyzed.

RESULTS

Of the 103 study subjects, 58 were male and 45 were female. Primary sites were lung (n = 58), breast (n = 12), colon (n = 6), kidney (n = 7), rectum (n = 6), and others (n = 14). Median survival duration from the diagnosis of brain metastasis was 25 months. Local treatment failure occurred in 14 of 77 the patients (77 lesions) with available gamma plan data. A lung cancer primary site was found to have a lower GKS failure rate than a breast or a renal site (p < 0.05). Lesions with a high Paddicks' CI or a low RTOG-CI had a higher rate of treatment failure (p < 0.05). Multivariate analysis revealed that primary tumor site and Paddick's CI were related to treatment failure (p < 0.05).

CONCLUSION

Brain metastases from renal and breast cancers had higher rates of local GKS treatment failure than those from lung cancer. Furthermore, high Paddick's CI revealed higher rate of local recurrence, and was not contributory to prevent local treatment failure. However, the enlargement of the diameter of the tumor after RS in the early follow-up period does not necessarily represent the poor outcome or need of retreatment.

Brain metastasis from uterine cervical cancer

Uterine cervical cancer usually spreads by local extension and through the rich lymphatic network to the retroperitoneal lymph nodes. However, brain metastasis from primary cervical cancer is extremely rare. They are usually seen late in the clinical course and have poor prognosis. We present a 48-year-old woman with squamous cell carcinoma of the cervix who developed multiple brain metastases after 30-month treatment of the primary disease. The patient received whole brain radiation therapy and steroids, and she is alive without any neurologic symptoms and signs at the 6-month follow-up after treatment of the recurrence.

Management of single brain metastasis: a practice guideline

QUESTIONS

Should patients with confirmed single brain metastasis undergo surgical resection? Should patients with single brain metastasis undergoing surgical resection receive adjuvant whole-brain radiation therapy (wbrt)? What is the role of stereotactic radiosurgery (srs) in the management of patients with single brain metastasis?

PERSPECTIVES

Approximately 15%-30% of patients with cancer will develop cerebral metastases over the course of their disease. Patients identified as having single brain metastasis generally undergo more aggressive treatment than do those with multiple metastases; however, in the province of Ontario, management of patients with single brain metastasis varies. Given that conflicting evidence has been reported, the Neuro-oncology Disease Site Group (dsg) of the Cancer Care Ontario Program in Evidence-based Care felt that a systematic review of the evidence and a practice guideline were warranted.

OUTCOMES

Outcomes of interest were survival, local control of disease, quality of life, and adverse effects.

METHODOLOGY

The medline, cancerlit, embase, and Cochrane Library databases and abstracts published in the proceedings of the annual meetings of the American Society of Clinical Oncology (1997-2005) and American Society for Therapeutic Radiology and Oncology (1998-2004) were systematically searched for relevant evidence. The review included fully published reports or abstracts of randomized controlled trials (rcts), nonrandomized prospective studies, and retrospective studies. The present systematic review and practice guideline has been reviewed and approved by the Neuro-oncology dsg, which comprises medical and radiation oncologists, surgeons, neurologists, a nurse, and a patient representative. External review by Ontario practitioners was obtained through an electronic survey. Final approval of the guideline report was obtained from the Report Approval Panel and the Neuro-oncology dsg.

RESULTS

QUALITY OF EVIDENCE

The literature search found three rcts that compared surgical resection plus wbrt with wbrt alone. In addition, a Cochrane review, including a meta-analysis of published data from those three rcts, was obtained. One rct compared surgical resection plus wbrt with surgical resection alone. One rct compared wbrt plus srs with wbrt alone. Evidence comparing srs with surgical resection or examining srs with or without wbrt was limited to prospective case series and retrospective studies.

BENEFITS

Two of three rcts reported a significant survival benefit for patients who underwent surgical resection as compared with those who received wbrt alone. Pooled results of the three rcts indicated no significant difference in survival or likelihood of dying from neurologic causes; however, significant heterogeneity was detected between the trials. The rct that compared surgical resection plus wbrt with surgical resection alone reported no significant difference in overall survival or length of functional independence; however, tumour recurrence at the site of the metastasis and anywhere in the brain was less frequent in patients who received wbrt as compared with patients in the observation group. In addition, patients who received wbrt were less likely to die from neurologic causes. Results of the rct that compared wbrt plus srs with wbrt alone indicated a significant improvement in median survival in patients who received srs. No quality evidence compares the efficacy of srs with surgical resection or examines the question of whether patients who receive srs should also receive wbrt.

HARMS

Pooled results of the three rcts that examined surgical resection indicated no significant difference in adverse effects between groups. Postoperative complications included respiratory problems, intracerebral hemorrhage, and infection. One rct reported no significant difference in adverse effects between patients who received wbrt plus srs and those who received wbrt alone.

PRACTICE GUIDELINE

TARGET POPULATION

The recommendations that follow apply to adults with confirmed cancer and a single brain metastasis. This practice guideline does not apply to patients with metastatic lymphoma, small-cell lung cancer, germ-cell tumour, leukemia, or sarcoma.

RECOMMENDATIONS

Surgical excision should be considered for patients with good performance status, minimal or no evidence of extracranial disease, and a surgically accessible single brain metastasis amenable to complete excision. Because treatment in cases of single brain metastasis is considered palliative, invasive local treatments must be individualized. Patients with lesions requiring emergency decompression because of intracranial hypertension were excluded from the rcts, but should be considered candidates for surgery. To reduce the risk of tumour recurrence for patients who have undergone resection of a single brain metastasis, postoperative wbrt should be considered. The optimal dose and fractionation schedule for wbrt is 3000 cGy in 10 fractions or 2000 cGy in 5 fractions. As an alternative to surgical resection, wbrt followed by srs boost should be considered for patients with single brain metastasis. The evidence is insufficient to recommend srs alone as a single-modality therapy.

QUALIFYING STATEMENTS

No high-quality data are available regarding the choice of surgery versus radiosurgery for single brain metastasis. In general, the size and location of the metastasis determine the optimal approach. The standard wbrt regimen for management of patients with single brain metastasis in the United States is 3000 cGy in 10 fractions, and this treatment is usually the standard arm in randomized studies of radiation in patients with brain metastases. Based solely on evidence, the understanding that no reason exists to choose 3000 cGy in 10 fractions over 2000 cGy in 5 fractions is correct; however, fraction size is believed to be important, and therefore 300 cGy daily (3000/10) is believed to be associated with fewer long-term neurocognitive effects than 400 cGy daily (2000/5) in the occasional long-term survivor. For that reason, many radiation oncologists in Ontario prefer 3000 cGy in 10 fractions. No data exist to either support or refute that preference; therefore, finding a resolution to this issue is not currently possible. The Neuro-oncology dsg will update the recommendations as new evidence becomes available.

Single-isocenter frameless intensity-modulated stereotactic radiosurgery for simultaneous treatment of multiple brain metastases: clinical experience

PURPOSE

To describe our clinical experience using a unique single-isocenter technique for frameless intensity-modulated stereotactic radiosurgery (IM-SRS) to treat multiple brain metastases.

METHODS AND MATERIALS

Twenty-six patients with a median of 5 metastases (range, 2-13) underwent optically guided frameless IM-SRS using a single, centrally located isocenter. Median prescription dose was 18 Gy (range, 14-25). Follow-up magnetic resonance imaging (MRI) and clinical examination occurred every 2-4 months.

RESULTS

Median follow-up for all patients was 3.3 months (range, 0.2-21.3), with 20 of 26 patients (77%) followed up until their death. For the remaining 6 patients alive at the time of analysis, median follow-up was 14.6 months (range, 9.3-18.0). Total treatment time ranged from 9.0 to 38.9 minutes (median, 21.0). Actuarial 6- and 12-month overall survivals were 50% (95% confidence interval [C.I.], 31-70%) and 38% (95% C.I., 19-56%), respectively. Actuarial 6- and 12-month local control (LC) rates were 97% (95% C.I., 93-100%) and 83% (95% C.I., 71-96%), respectively. Tumors <or=1.5 cm had a better 6-month LC than those >1.5 cm (98% vs. 90%, p = 0.008). New intracranial metastatic disease occurring outside of the treatment volume was observed in 7 patients. Grade >or=3 toxicity occurred in 2 patients (8%).

CONCLUSION

Frameless IM-SRS using a single-isocenter approach for treating multiple intracranial metastases can produce clinical outcomes that compare favorably with those of conventional SRS in a much shorter treatment time (<40 minutes). Given its faster treatment time, this technique is appealing to both patients and personnel in busy clinics.

The role of stereotactic radiosurgery in the management of patients with newly diagnosed brain metastases: a systematic review and evidence-based clinical practice guideline

QUESTION

Should patients with newly-diagnosed metastatic brain tumors undergo stereotactic radiosurgery (SRS) compared with other treatment modalities? Target population These recommendations apply to adults with newly diagnosed solid brain metastases amenable to SRS; lesions amenable to SRS are typically defined as measuring less than 3 cm in maximum diameter and producing minimal (less than 1 cm of midline shift) mass effect. Recommendations SRS plus WBRT vs. WBRT alone Level 1 Single-dose SRS along with WBRT leads to significantly longer patient survival compared with WBRT alone for patients with single metastatic brain tumors who have a KPS > or = 70.Level 1 Single-dose SRS along with WBRT is superior in terms of local tumor control and maintaining functional status when compared to WBRT alone for patients with 1-4 metastatic brain tumors who have a KPS > or =70.Level 2 Single-dose SRS along with WBRT may lead to significantly longer patient survival than WBRT alone for patients with 2-3 metastatic brain tumors.Level 3 There is class III evidence demonstrating that single-dose SRS along with WBRT is superior to WBRT alone for improving patient survival for patients with single or multiple brain metastases and a KPS<70 [corrected].Level 4 There is class III evidence demonstrating that single-dose SRS along with WBRT is superior to WBRT alone for improving patient survival for patients with single or multiple brain metastases and a KPS < 70. SRS plus WBRT vs. SRS alone Level 2 Single-dose SRS alone may provide an equivalent survival advantage for patients with brain metastases compared with WBRT + single-dose SRS. There is conflicting class I and II evidence regarding the risk of both local and distant recurrence when SRS is used in isolation, and class I evidence demonstrates a lower risk of distant recurrence with WBRT; thus, regular careful surveillance is warranted for patients treated with SRS alone in order to provide early identification of local and distant recurrences so that salvage therapy can be initiated at the soonest possible time. Surgical Resection plus WBRT vs. SRS +/- WBRT Level 2 Surgical resection plus WBRT, vs. SRS plus WBRT, both represent effective treatment strategies, resulting in relatively equal survival rates. SRS has not been assessed from an evidence-based standpoint for larger lesions (>3 cm) or for those causing significant mass effect (>1 cm midline shift). Level 3: Underpowered class I evidence along with the preponderance of conflicting class II evidence suggests that SRS alone may provide equivalent functional and survival outcomes compared with resection + WBRT for patients with single brain metastases, so long as ready detection of distant site failure and salvage SRS are possible. SRS alone vs. WBRT alone Level 3 While both single-dose SRS and WBRT are effective for treating patients with brain metastases, single-dose SRS alone appears to be superior to WBRT alone for patients with up to three metastatic brain tumors in terms of patient survival advantage.

Gamma Knife surgery for brain metastases from gastrointestinal cancer

OBJECT

Brain metastases from gastrointestinal cancers are rare. However, the incidence is increasing because patients with gastrointestinal carcinoma tend to live longer due to earlier diagnosis and more effective treatment of systemic disease. The purpose of this study was to evaluate the efficacy of Gamma Knife surgery (GKS) for the treatment of brain metastases from gastrointestinal cancers.

METHODS

The authors performed a retrospective review of 40 patients (18 women and 22 men) who had undergone GKS to treat a total of 118 metastases from gastrointestinal cancers between January 1996 and December 2006. The mean patient age was 58.7 years, and the mean Karnofsky Performance Scale (KPS) score was 70. There were 7 patients with esophageal cancer, 25 with colon cancer, 5 with rectal cancer, 2 with pancreatic cancer, and 1 with gastric cancer. Nineteen patients were treated with whole-brain radiotherapy and/or local brain radiotherapy before GKS. Twenty-four patients had extracranial metastases, and 3 had an additional primary cancer. The mean metastatic brain tumor volume was 4.3 cm3, and the mean maximum tumor dose varied from 17.1 to 76.7 Gy (mean 41.8 Gy).

RESULTS

Follow-up imaging studies were available in 25 patients with a total of 90 treated metastases. The results demonstrate a tumor control rate of 91%. The median survival time was 6.7 months, and the 6-month and 1-year survival rates were 55 and 25%, respectively. A univariate analysis revealed that the KPS score (<or=70 vs >or=80) was significant (p=0.018) for improved survival.

CONCLUSIONS

Results in this series suggest that GKS can be an effective tool for the treatment of brain metastases from gastrointestinal cancer.

Relationship between volume, dose and local control in stereotactic radiosurgery of brain metastasis

The aim of this study is to analyse the efficacy of linear accelerator stereotactic radiosurgery (SRS) on prognostic factors, local control rate and survival in patients with brain metastasis. Patients with either a single metastasis or up to 4 multiple brain metastases with a maximum tumour diameter of 40 mm for each tumour and a Karnofsky Performance Status (KPS) > or = 70 were eligible for SRS. SRS was applied to 150 lesions in 86 consecutive patients with a median age of 60 years (median 1 and mean 1.7 lesions per patient, mean KPS 86). Median overall survival was 6.2 months after SRS and 9.7 months from diagnosis of brain metastasis. Multivariate analysis revealed that a KPS of 90 or more (p = 0.009) and female sex (p = 0.003) were associated with a longer survival. Radiation dose < or = 15 Gy (p = 0.017) and KPS < 90 (p = 0.013) were independent predictors of a shorter time to local failure. Five patients showed evidence of radionecrosis with a median survival of 14.8 months. Addition of WBRT neither led to improvement of survival nor to improvement of local control. Improved local control following SRS for brain metastases was associated with KPS > or =90, a radiation dose > 15 Gy and a PTV < 13 cc. The potential of hypofractionated stereotactic radiotherapy (SRT) for brain metastases of larger volume warrants further study.

Stereotactic radiosurgery for metastatic brain tumors: a comprehensive review of complications

Object

Stereotactic radiosurgery (SRS) is commonly used to treat brain metastases. Complications associated with this treatment are underreported. The authors reviewed a large series of patients who underwent SRS for brain metastases to identify complications and factors predicting their occurrence.

Methods

Prospectively collected clinical data from 273 patients undergoing SRS for 1 or 2 brain metastases at The University of Texas M. D. Anderson Cancer Center between June 1993 and December 2004 were reviewed. Patients who had received prior treatment for their tumor, including whole-brain radiation, SRS, or surgery, were excluded from the study. Data on adverse neurological and nonneurological outcomes following treatment were collected.

Results

Three hundred sixteen lesions were treated. Complications were associated with 127 (40%) of 316 treated lesions. New neurological complications were associated with 101 (32%) of 316 lesions. The onset of seizure was the most common complication, occurring in 41 (13%) of 316 SRS cases. On multivariate analysis, progressing primary cancer (hazard ratio [HR] = 2.4, 95% CI 1.6–3.6, p < 0.001), tumor location in eloquent cortex (HR = 2.3, 95% CI 1.6–3.4, p < 0.001), and lower (< 15 Gy) SRS dose (HR = 2.1, 95% CI 1.1–4.2, p = 0.04) were significantly associated with new complications. On multivariate analysis, a tumor location in the eloquent cortex (HR = 2.5, 95% CI 1.6–3.8, p < 0.001) and progressing primary cancer (HR = 1.6, 95% CI 1.1–2.5, p = 0.03) were significantly associated with new neurological complications.

Conclusions

The authors showed that new neurological and nonneurological complications were associated with 40% of SRS treatments for brain metastases. Patients with lesions in functional brain regions have a significantly increased risk of treatment-related complications.

Optically-guided frameless linac-based radiosurgery for brain metastases: clinical experience

The purpose of this study was to describe our clinical experience using optically-guided linear accelerator (linac)-based frameless stereotactic radiosurgery (SRS) for the treatment of brain metastases. Sixty-five patients (204 lesions) were treated between 2005 and 2008 with frameless SRS using an optically-guided bite-block system. Patients had a median of 2 lesions (range, 1-13). Prescription dose ranged from 14 to 22 Gy (median, 18 Gy) and was given in a single fraction. Clinical and radiographic evaluation occurred every 2-4 months following treatment. At a median follow-up of 6.2 months, actuarial survival at 12 months was 40% [95% confidence interval (CI), 28-52). Of 135 lesions that were evaluable for local control (LC), 119 lesions (88%) did not show evidence of progression. Actuarial 12 month LC was 76% (95% CI, 66-86). Tumors <or=2 cm in size had a better 12 month LC rate (81% vs. 36%, P = 0.017) than those >2 cm. Adverse events occurred in three patients (5%). Optically-guided linac-based frameless SRS can produce clinical outcomes that compare favorably to frame-based techniques. As this technique is convenient to use and allows for the uncomplicated delivery of hypofractionated radiotherapy, frameless SRS will likely have an increasingly important role in the management of brain metastases.

Intracranial application of IMRT based radiosurgery to treat multiple or large irregular lesions and verification of infra-red frameless localization system

We have employed a frameless localization system for intracranial radiosurgery, utilizing a custom biteblock with fiducial markers and an infra-red camera for set-up and monitoring patient position. For multiple brain metastases or large irregular lesions, we use a single-isocenter intensity-modulated approach. We report our quality assurance measurements and our experience using Intensity Modulated Radiosurgery (IMRS) to treat such intracranial lesions. A phantom with integrated targets and fiducial markers was utilized to test the positional accuracy of the system. The frameless localization system was used for patient setup and target localization as well as for motion monitoring during treatment. Inverse optimization planning gave satisfactory dose coverage and critical organ sparing. Patient setup was guided by the infrared camera through fine adjustment in three translational and three rotational degrees for isocenter localization and verified by orthogonal kilovoltage (kV) images, taken before treatment to ensure the accuracy of treatment. The relative localization of the camera based system was verified to be highly accurate along three translational directions of couch motion and couch rotation. After verification, we began treating patients with this technique. About 8–12 properly selected fixed beams with a single isocenter were sufficient to achieve good dose coverage and organ sparing. Portal dosimetry with an Electronic Portal Imaging Device (EPID) and kV images provided excellent quality assurance for the IMRS plan and patient setup. The treatment time was less than 60 min to deliver doses of 16–20 Gy in a single fraction. The camera-based system was verified for positional accuracy and was deemed sufficiently accurate for stereotactic treatments. Single isocenter IMRS treatment of multiple brain metastases or large irregular lesions can be done within an acceptable treatment time and gives the benefits of dose-conformity and organ-sparing, easy plan QA, and patient setup verification.

Technological advances in radiation oncology for central nervous system tumors

Advances in computer software technology have led to enormous progress that has enabled increasing levels of complexity to be incorporated into radiotherapy treatment planning systems. Because of these changes, the delivery of radiotherapy evolved from therapy designed primarily on plain 2-dimensional X-ray images and hand calculations to therapy based on 3-dimensional images incorporating increasingly complex computer algorithms in the planning process. In addition, challenges in treatment planning and radiation delivery, such as problems with setup error and organ movement, have begun to be systematically addressed, ushering in an era of so-called 4-dimensional radiotherapy. This review article discusses how these advances have changed the way in which many common neoplasms of the central nervous system are being treated at present.

Stereotactic radiotherapy for patients who initially presented with brain metastases from non-small cell carcinoma

The purpose of this study was retrospectively to evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) for patients who presented with intracranial metastases as the initial symptom of lung carcinoma. Fifteen patients with three or fewer brain metastases from lung carcinoma underwent FSRT receiving 42 Gy in 7 fractions or 40 Gy in 4 fractions from April 1999 to October 2002. Patients who developed new lesions were retreated with FSRT or whole brain radiotherapy (WBRT). Tumor control was obtained in 14 patients during a median period of 21.0 months (ranging from 11 to 34 months) with salvage radiotherapy whenever required. None died from brain metastasis. The median survival time was 7.0+/-3.0 months and 21.0+/-1.0 months for patients with or without extracranial metastases, respectively (p<0.01). Those who received treatment for the primary and mediastinal lymph nodes (22.0+/-1.4 months) survived longer than those who did not (8.0+/-2.5 months) (p<0.001). Overall high local control and high survival rates for the patients suggest that FSRT appears effective and safe in the treatment of patients who present with intracranial metastases as the initial symptom of lung carcinoma. After treatment of intracranial metastases, further therapy for the primary appears to improve survival rates.

Clinical results of stereotactic body frame based fractionated radiation therapy for primary or metastatic thoracic tumors

The aim of this study was to evaluate the treatment outcomes of stereotactic body radiation therapy for treating primary or metastatic thoracic tumors using a stereotactic body frame. Between January 1998 and February 2004, 101 lesions from 91 patients with thoracic tumors were prospectively reviewed. A dose of 10-12 Gy per fraction was given three to four times over consecutive days to a total dose of 30-48 Gy (median 40 Gy). The overall response rate was 82%, with 20 (22%) complete responses and 55 (60%) partial responses. The one- and two-year local progression free survival rates were 90% and 81%, respectively. The patients who received 48 Gy showed a better local tumor control than those who received less than 48 Gy (Fisher exact test; p = 0.004). No pulmonary complications greater than a RTOG toxicity criteria grade 2 were observed. The experience of stereotactic body frame based radiation therapy appears to be a safe and promising treatment modality for the local management of primary or metastatic lung tumors. The optimal total dose, fractionation schedule and treatment volume need to be determined after a further follow-up of these results.

Risk of intracranial hemorrhage and cerebrovascular accidents in non-small cell lung cancer brain metastasis patients

BACKGROUND

Brain metastases confer significant morbidity and a poorer survival in non-small cell lung cancer (NSCLC). Vascular endothelial growth factor-targeted antiangiogenic therapies (AAT) have demonstrated benefit for patients with metastatic NSCLC and are expected to directly inhibit the pathophysiology and morbidity of brain metastases, yet patients with brain metastases have been excluded from most clinical trials of AAT for fear of intracranial hemorrhage (ICH). The underlying risk of ICH from NSCLC brain metastases is low, but needs to be quantitated to plan clinical trials of AAT for NSCLC brain metastases.

METHODS

Data from MD Anderson Cancer Center Tumor Registry and electronic medical records from January 1998 to March 2006 was interrogated. Two thousand one hundred forty-three patients with metastatic NSCLC registering from January 1998 to September 2005 were followed till March 2006. Seven hundred seventy-six patients with and 1,367 patients without brain metastases were followed till death, date of ICH, or last date of study, whichever occurred first.

RESULTS

The incidence of ICH seemed to be higher in those with brain metastasis compared with those without brain metastases, in whom they occurred as result of cerebrovascular accidents. However, the rates of symptomatic ICH were not significantly different. All ICH patients with brain metastasis had received radiation therapy for them and had been free of anticoagulation. Most of the brain metastasis-associated ICH's were asymptomatic, detected during increased radiologic surveillance. The rates of symptomatic ICH, or other cerebrovascular accidents in general were similar and not significantly different between the two groups.

CONCLUSIONS

In metastatic NSCLC patients, the incidence of spontaneous ICH appeared to be higher in those with brain metastases compared with those without, but was very low in both groups without a statistically significant difference. These data suggest a minimal risk of clinically significant ICH for NSCLC brain metastasis patients and proposes having more well designed prospective trail to see the role of AAT in this patient population.

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.

Radiosurgery for recurrent brain metastases after whole-brain radiotherapy : factors affecting radiation-induced neurological dysfunction

OBJECTIVE

We retrospectively analyzed survival, local control rate, and incidence of radiation toxicities after radiosurgery for recurrent metastatic brain lesions whose initial metastases were treated with whole-brain radiotherapy. Various radiotherapeutical indices were examined to suggest predictors of radiation-related neurological dysfunction.

METHODS

In 46 patients, total 100 of recurrent metastases (mean 2.2, ranged 1-10) were treated by CyberKnife radiosurgery at average dose of 23.1 Gy in 1 to 3 fractions. The median prior radiation dose was 32.7 Gy, the median time since radiation was 5.0 months, and the mean tumor volume was 12.4 cm(3). Side effects were expressed in terms of radiation therapy oncology group (RTOG) neurotoxicity criteria.

RESULTS

Mass reduction was observed in 30 patients (65%) on MRI. After the salvage treatment, one-year progression-free survival rate was 57% and median survival was 10 months. Age (<60 years) and tumor volume affected survival rate (p=0.03, each). Acute (</=1 month) toxicity was observed in 22% of patients, subacute and chronic (>6 months) toxicity occurred in 21%, respectively. Less acute toxicity was observed with small tumors (<10 cm(3), p=0.03), and less chronic toxicity occurred at lower cumulative doses (<100 Gy, p=0.004). "Radiation toxicity factor" (cumulative dose times tumor volume of <1,000 Gyxcm(3)) was a significant predictor of both acute and chronic CNS toxicities.

CONCLUSION

Salvage CyberKnife radiosurgery is effective for recurrent brain metastases in previously irradiated patients, but careful evaluation is advised in patients with large tumors and high cumulative radiation doses to avoid toxicity.

Gamma knife radiosurgery as a therapeutic strategy for intracranial sarcomatous metastases

PURPOSE

To determine the indication and outcomes for Gamma Knife stereotactic radiosurgery (GKSRS) in the care of patients with intracranial sarcomatous metastases.

METHODS AND MATERIALS

Data from 21 patients who underwent radiosurgery for 60 sarcomatous intracranial metastases (54 parenchymal and 6 dural-based) were studied. Nine patients had radiosurgery for solitary tumors and 12 for multiple tumors. The primary pathology was metastatic leiomyosarcoma (4 patients), osteosarcoma (3 patients), soft-tissue sarcoma (5 patients), chondrosarcoma (2 patients), alveolar soft part sarcoma (2 patients), and rhabdomyosarcoma, Ewing's sarcoma, liposarcoma, neurofibrosarcoma, and synovial sarcoma (1 patient each). Twenty patients received multimodality management for their primary tumor, and 1 patient had no evidence of systemic disease. The mean tumor volume was 6.2 cm(3) (range, 0.07-40.9 cm(3)), and a median margin dose of 16 Gy was administered. Three patients had progressive intracranial disease despite fractionated whole-brain radiotherapy before SRS.

RESULTS

A local tumor control rate of 88% was achieved (including patients receiving boost, up-front, and salvage SRS). New remote brain metastases developed in 7 patients (33%). The median survival after diagnosis of intracranial metastasis was 16 months, and the 1-year survival rate was 61%.

CONCLUSIONS

Gamma Knife radiosurgery was a well-tolerated and initially effective therapy in the management of patients with sarcomatous intracranial metastases. However, many patients, including those who also received fractionated whole-brain radiotherapy, developed progressive new brain disease.

Brain metastases: current management and new developments

PURPOSE OF REVIEW

To review the state-of-the-art and new developments in the management of patients with brain metastases.

RECENT FINDINGS

Treatment decisions are based on prognostic factors to maximize neurologic function and survival, while avoiding unnecessary therapies. Whole-brain radiotherapy (WBRT) is the treatment of choice for patients with unfavorable prognostic factors. Stereotactic radiosurgery (SRS) or surgery is indicated for patients with favorable prognostic factors and limited brain disease. In single brain metastasis, the addition of either stereotactic radiosurgery or surgery to WBRT improves survival. The omission of WBRT after surgery or radiosurgery results in a worse local and distant control, though it does not affect survival. The incidence of neurocognitive deficits in long-term survivors after WBRT remains to be defined. New approaches to avoid cognitive deficits following WBRT are being investigated. The role of chemotherapy is limited. Molecularly targeted therapies are increasingly employed. Prophylaxis with WBRT is the standard in small-cell lung cancer.

SUMMARY

Many questions need future trials: the usefulness of new radiosensitizers; the role of local treatments after surgery; and the impact of molecularly targeted therapies on subgroups of patients with specific molecular profiles. Quality of life and cognitive functions are recognized as major endpoints in clinical trials.

Treatment of malignant tumors of the skull base with multi-session radiosurgery

OBJECTIVE

Malignant tumors that involve the skull base pose significant challenges to the clinician because of the proximity of critical neurovascular structures and limited effectiveness of surgical resection without major morbidity. The purpose of this study was to evaluate the efficacy and safety of multi-session radiosurgery in patients with malignancies of the skull base.

METHODS

Clinical and radiographic data for 37 patients treated with image-guided, multi-session radiosurgery between January 2002 and December 2007 were reviewed retrospectively. Lesions were classified according to involvement with the bones of the base of the skull and proximity to the cranial nerves.

RESULTS

Our cohort consisted of 37 patients. Six patients with follow-up periods less than four weeks were eliminated from statistical consideration, thus leaving the data from 31 patients to be analyzed. The median follow-up was 37 weeks. Ten patients (32%) were alive at the end of the follow-up period. At last follow-up, or the time of death from systemic disease, tumor regression or stable local disease was observed in 23 lesions, representing an overall tumor control rate of 74%. For the remainder of lesions, the median time to progression was 24 weeks. The median progression-free survival was 230 weeks. The median overall survival was 39 weeks. In the absence of tumor progression, there were no cranial nerve, brainstem or vascular complications referable specifically to CyberKnife radiosurgery.

CONCLUSION

Our experience suggests that multi-session radiosurgery for the treatment of malignant skull base tumors is comparable to other radiosurgical techniques in progression-free survival, local tumor control, and adverse effects.

Biological optimization of tumor radiosurgery

In tumor radiosurgery, a high dose of radiation is delivered in a single session. The question then naturally arises of selecting an irradiation strategy of high biological efficiency. In this study, the authors propose a mathematical framework to investigate the biological effects of heterogeneity and rate of dose delivery in radiosurgery. The authors simulate a target composed by proliferating and hypoxic tumor cells as well as by normal tissue. Treatment outcome is evaluated by a functional of the dose distribution that counts the LQ-surviving fractions of each cell type. Prescriptions on intensity, homogeneity, and duration of radiation delivery are incorporated as constraints. Biological optimization is performed by means of calculus of variation techniques. For a fixed dose, increasing heterogeneity considerably improved the biological performance. The dose peaks progressively concentrated in the hypoxic and proliferating areas, while damage to normal tissue was reduced. The duration of delivery, optimized in the range of 1-30 min and for various tumor/normal characteristic DNA repair time ratios, coincided with the maximum allowed value. It resulted in a poor therapeutic gain, which was positively correlated with the tumor/normal characteristic DNA repair time ratio. The mathematical framework described in this work allows one to design the dose distribution and dose rate of biologically based plans for tumor radiosurgery. It may be thus integrated into the available simulation softwares to assist in treatment planning.

Prognostic factors and grading systems for overall survival in patients treated with radiosurgery for brain metastases: variation by primary site

OBJECT

The authors conducted a study to determine whether prognostic factors and the applicability of prognostic systems vary by primary tumor site in patients treated with radiosurgery for brain metastases.

METHODS

The authors evaluated data obtained in patients who underwent radiosurgery with or without whole-brain radiotherapy (WBRT) from 1991 to 2005 for newly diagnosed brain metastases. Four groups were analyzed: 1) all primary sites combined, 2) breast, 3) lung, and 4) melanoma primary sites. Kaplan-Meier, log-rank, Cox proportional hazard uni- and multivariate analysis, and recursive partitioning analysis (RPA) were used to assess prognostic factors and 4 prognostic systems: Radiation Therapy Oncology Group (RTOG) RPA, Graded Prognostic Assessment (GPA), basic score for brain metastases (BSBM), and the newly proposed Golden grading system (GGS). The GGS divides patients into 4 prognostic groups by age >or= 65 years, Karnofsky Performance Scale (KPS) score < 70, and known presence of extracranial metastases.

RESULTS

Data acquired in 479 newly diagnosed patients with 1664 lesions were analyzed. The median survival time from diagnosis of brain metastases was 12.1 months; the median follow-up was 25.4 months in 73 patients who were censored. Survival and prognostic factors were equivalent for 369 patients treated with radiosurgery compared with 110 patients treated with radiosurgery and WBRT, so these subsets were combined. Multivariate analysis of all primary sites combined demonstrated age < 65 years, KPS score >or= 70, no known extracranial metastases, and <or= 3 brain metastases were associated with longer survival, and primary tumor control was not. In subgroup multivariate analysis of patients with breast, lung, or melanoma primaries, favorable factors included only primary tumor control in 87 patients with breast primary; age < 65 years, no known extracranial metastases, and <or= 3 brain metastases in 169 patients with lung primary; and KPS >or= 70 years, primary tumor control, and <or= 3 brain metastases in 137 patients with melanoma primary. The median survival for <or= 3 versus > 3 metastases was 15.6 and 16.9 months, respectively, for breast, 16.5 and 11.3 months for lung, and 9.0 and 5.7 months for melanoma. Analysis of the 4 prognostic systems (RTOG RPA, BSBM, GPA, and GGS) showed that each prognostic system's clinical applicability varied depending on primary tumor site. The RPA confirmed that GGS and primary tumor site are significant variables for prognosis.

CONCLUSIONS

Favorable prognostic factors for patients with newly diagnosed brain metastases treated with radiosurgery vary by primary site. The 4 prognostic grading systems analyzed were applicable to different primary sites depending on which prognostic factors each individual system incorporated. Therefore, the authors recommend further development and use of primary-specific prognostic systems.

Gamma knife radiosurgery for metastatic brain tumors from thyroid cancer

OBJECTIVE

We report our experience using gamma knife radiosurgery (GKR) for brain metastasis from thyroid cancer, which is extremely rare.

METHODS

Between 1995 and 2007, 9 patients with 26 metastatic brain tumor(s) from thyroid cancer underwent GKR. The mean patient age was 58 years (range: 10-78). Seven patients had metastases from papillary thyroid cancer, and two from medullary thyroid cancer. Five patients had solitary tumors, and four patients had multiple metastases. Three patients who had multiple metastases also underwent whole brain radiation therapy (WBRT). The mean tumor volume was 2.4 cc (range: 0.03-14.0). A median margin dose of 18.0 Gy (range: 12-20) was delivered to the tumor margin.

RESULTS

Tumor control was obtained in 25 out of 26 tumors (96%). The median progression-free period after GKR was 12 months (range: 4-53). The overall median survival after GKR was 33 months (range: 5-54). There were no procedure-related complications and six patients are still living 5-54 months after GKR.

CONCLUSIONS

Radiosurgery is an effective and minimally invasive strategy for management of brain metastases form thyroid cancer.

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.

Endoscopic removal of a central neurocytoma from the posterior third ventricle

Central neurocytoma is a rare benign tumor that most commonly arises within the ventricular system of young adults. Its occurrence in the posterior third ventricle is one of the least reported presentations. These tumors are usually treated by a combination of either biopsy or open surgical resection, often followed by radiation (Gamma knife or Novalis) with or without chemotherapy. A 37-year-old woman with a posterior third ventricle neurocytoma presented with acute signs of aqueductal stenosis. The patient underwent endoscopic assisted gross total resection of the tumor with the aid of intraoperative laser followed by standard third ventriculostomy; no further treatment was required. The patient did not develop any subsequent neurological deficit. A 36-month follow-up was still consistent with a normal neurological examination. Serial post-operative MRIs show neither residual nor recurrent tumor. Thus, posterior third ventricle central neurocytomas are relatively benign tumors that can be successfully removed using a minimally invasive approach, thereby avoiding both the morbidity related to conventional open craniotomy and the potential toxicity of any adjuvant treatment.

Salvage stereotactic radiosurgery effectively treats recurrences from whole-brain radiation therapy

BACKGROUND

The purpose of the current study was to examine overall survival (OS) and time to local failure (LF) in patients who received salvage stereotactic radiosurgery (SRS) for recurrent brain metastases (BM) after initial management that included whole-brain radiation therapy (WBRT).

METHODS

The records of 1789 BM patients from August 1989 to November 2004 were reviewed. Of these, 111 underwent WBRT as part of their initial management and SRS as salvage. Patients were stratified by Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis class, primary disease, dimension of the largest metastases and number of BM at initial diagnosis, and time to first brain recurrence after WBRT. Overall survival, survival after SRS, and time to local and distant failure were analyzed.

RESULTS

The median OS from the initial diagnosis of BM was 17.7 months. Median survival after salvage SRS for the entire cohort was 9.9 months. Median survival after salvage SRS was 12.3 months in patients who had their first recurrence >6 months after WBRT versus 6.8 months for those who developed disease recurrence < or = 6 months after (P = .0061). Primary tumor site did not appear to affect survival after SRS. Twenty-eight patients (25%) developed local recurrence after their first SRS with a median time of 5.2 months. A dose <22 grays and lesion size >2 cm were found to be predictive of local failure.

CONCLUSIONS

In this study, patients who recurred after WBRT and were treated with salvage SRS were found to have good local control and survival after SRS. WBRT provided good initial control, as 45% of these patients failed >6 months after WBRT. Those with a longer time to failure after WBRT had significantly longer survival after SRS.

Treatment strategies in CNS metastases

BACKGROUND

CNS metastases constitute the most common brain malignancy in adults and, therefore, represent a challenging issue in cancer treatment.

PURPOSE

To review the role and indication of the various treatment options in the context of important prognostic factors that may guide the selection of patients who could benefit from each treatment modality.

METHODS

Therapeutic approaches in treating CNS metastases include surgery, radiotherapy and systemic chemotherapy, and are reviewed through a critical evaluation of published recent literature; however, in the majority of most common malignancies spreading to the CNS, treatment remains largely palliative and rarely curative, as is the case for other metastastic sites.

CONCLUSIONS

It is anticipated that a multidisciplinary approach with rapid integration of new treatment strategies is required for the treatment of patients developing CNS metastases, ultimately aiming to prolong survival, preserve neurologic function and improve quality of life.

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.

Three-dimensional Gaussian model to define brain metastasis limits on 11C-methionine PET

PURPOSE

Since 11C-methionine (MET) heavily accumulates in brain tumors, PET with MET (MET-PET) is proposed for the image-guided planning of their targeted therapy. Determination of bulk tumor limits is therefore a crucial component of MET-PET image analysis. We aimed at validating a Gaussian model of tumor delineation on MET-PET. We choose MET-PET and MRI data obtained in brain metastases to adjust the model. Indeed, MRI limits of these non-infiltrative hypermetabolic brain lesions are efficiently used for their curative treatment.

METHODS AND MATERIALS

We developed a three-dimensional (3D) Gaussian model that relates the tumor-limit-defining threshold to maximum and mean count values in the defined tumor volume and to mean count values in a reference region. To adjust the model to experimental data, we selected 25 brain metastases following these criteria: (i) no surgery or classical radiotherapy within 6 months, (ii) no previous radiosurgery, (iii) MET-PET and MRI acquired within a 48-h interval, (vi) necrosis representing less than 25% of tumor volume on MRI. We applied a progressive thresholding procedure on MET-PET so as to match tumor limits on contrast-enhanced co-registered MRI.

RESULTS

In 22 tumors, a match could be reached between tumor margins on MET-PET and MRI. The relation between mean, maximum and threshold values closely fits the 3D-Gaussian model function. We found a quadratic relation between the mean-to-threshold ratio and the maximum-to-cerebellum activity ratio.

CONCLUSIONS

A 3D-Gaussian model may describe the limits of MET uptake distribution within brain metastases, providing a simple method for metabolic tumor delineation.

[Current management of brain metastases]

INTRODUCTION

Cerebral metastases occur in 15 to 20% of cancers and their incidence is increasing. The majority occur at an advanced stage of the disease, but metastasis may be the inaugural sign of cancer. The aim of treatments, which are often palliative, is to preserve the neurological status of the patient with the best quality of life.

STATE OF ART

Corticosteroids are widely used for symptomatic palliation, requiring close monitoring and regular dose adaptation. Antiepileptic drugs should be given only for patients who have had a seizure. In case of multiple cerebral metastases occurring at an advanced stage of the disease, whole brain radiation is the most effective therapy for rapid symptom control. However, radiotherapy moderately improves overall survival, which often depends on the progression of disseminated systemic disease. On the contrary, surgery is indicated in case of a solitary metastasis, particularly when the patient is young (less than 65 years), with good general status (Karnofsky greater than 70), and when the systemic disease is under control. Radiosurgery offers an attractive alternative for these patients with good prognostic factors and a small number of cerebral metastases (< or = 4).

PERSPECTIVES

Chemotherapy, considered in the past as not effective, is taking on a more important place in patients with multiple nonthreatening metastases from chemosensitive cancers (breast, testes...). Radiosurgery and whole brain radiotherapy are complementary techniques. Their respective role in the management of multiple metastases (< 4) remains to be further investigated.

CONCLUSIONS

Therapeutic options are increasingly effective to improve the functional prognosis of patients with cerebral metastases. Ideally, a multidisciplinary assessment offers the best choice of therapeutic modalities.