Linac stereotactic radiosurgery: An effective and safe treatment for elderly patients with brain metastases

Clinical Results and Hematologic Predictors of Linear Accelerator-Based Stereotactic Radiosurgery or Fractionated Stereotactic Radiotherapy for Brain Metastasis in Patients Aged 75 Years or Older: A Retrospective Study

OBJECTIVE

This study aimed to evaluate prognostic factors including pre-radiosurgical blood count in elderly patients (EPs) with brain metastasis (BM) who were treated using linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (fSRT) with a micro-multileaf collimator.

METHODS

Between January 2011 and November 2021, 101 consecutive EPs with BM were treated by LINAC-based SRS or fSRT using LINAC with a micro-multileaf collimator. EPs were defined as patients aged ≥75 years.

RESULTS

The tumors originated from the lungs (n = 90; 89.1%), colon (n = 2; 2.0%), and others (n = 9; 8.8%) in these EPs. The median pretreatment Karnofsky Performance Status was 80 (range, 40-100). The median follow-up time was 10 months (range, 0-76), as was the median survival. The 6-month, 1-year, and 2-year survival in the EP group was 58.3%, 43.2%, and 28.5%, respectively. Freedom from local failure at 6 months and 1 and 2 years was 97%, 95%, and 91.5%, respectively. Freedom from distant failure at 6 months and 1 and 2 years in EPs was 70.6%, 59.4%, and 54.2%, respectively. A high neutrophil/lymphocyte ratio >5.33 was an unfavorable predictor of prognosis for EPs with BMs treated with SRS and fSRT (P < 0.001). In the EPs, the prognostic factors associated with prolonged survival in the Cox proportional hazards model were being female and a good pretreatment Karnofsky Performance Status.

CONCLUSIONS

The findings of our study highlight the efficacy of LINAC-based SRS and fSRT with a micro-multileaf collimator in the treatment of EPs with BMs. Neutrophil/lymphocyte ratio can be an important factor in treatment decisions for EPs with BMs.

Robotic stereotactic radiosurgery for intracranial meningiomas in elderly patients: assessment of treatment efficacy and safety

Purpose

Stereotactic radiosurgery (SRS) has been increasingly used to treat intracranial pathologies in elderly patients. The treatment efficiency of SRS has been demonstrated in meningiomas, with excellent local control. We aimed to analyze the safety of robotic SRS in elderly patients with meningiomas.

Methods

We searched for patients with suspected WHO °I meningioma ≥ 60 years old, who underwent CyberKnife (CK) SRS from January 2011 to December 2021. Tumor localization was categorized using the "CLASS" algorithmic scale. Tumor response was evaluated using the Response Assessment in Neuro-Oncology (RANO) criteria for meningiomas. Adverse effects were graded using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 and a cox regression was performed to investigate possible predictors.

Results

We identified 82 patients with 102 CK-treated lesions that matched the criteria for the first SRS. The median age was 70 [IQR 64-75] years, and 24.3% of the patients were aged > 75 years. Multiple lesions (up to six) were treated in 14.1% of the SRS-sessions. A previous surgery was performed in 57.3% of lesions, with a median time interval of 41 [IQR 10 - 58] months between the initial surgical procedure and the SRS treatment. In 47.9% of cases, CLASS 3 meningiomas at high-risk locations were irradiated. Single fraction radiosurgery was applied to 62.5% of the lesions, while in the remaining cases multi-session SRS with three to five fractions was used. During the median follow-up period of 15.9 months, lesion size progression was observed in 3 cases. Karnofsky Performance Status (KPS) declined by ≥ 20 points in four patients. Adverse effects occurred in 13 patients, while only four patients had CTCAE ≥2 toxicities. Hereby only one of these toxicities was persistent. The occurrence of complications was independent of age, planned target volume (PTV), high-risk localization, and surgery before SRS.

Conclusion

The data indicates that SRS is a safe, efficient, and convenient treatment modality for elderly patients with meningioma, even at high-risk locations.

CyberKnife-based stereotactic radiosurgery or fractionated stereotactic radiotherapy in older patients with brain metastases from non-small cell lung cancer

PURPOSE

We analyzed clinical results of CyberKnife (CK)-based stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT) in older patients (age ≥65 years) affected by brain metastases (BM) from non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Forty-three older patients with 92 BM were treated with CK-based SRS/FSRT at our institution between 2009 and 2019. The end-point was overall survival (OS). Univariate and multivariate analyses were performed to identify the prognostic factors influencing OS. The in-field local control (IFLC) within the SRS/FSRT field was also assessed.

RESULTS

During a median follow-up period of 18 months, the median OS was 32 months. NSCLC-specific graded prognostic assessment (GPA) (p = 0.027) was an independent significant factor affecting OS in the multivariate analysis. The median IFLC period was 31 months, and the total BM volume (p = 0.025) appeared to be a significant feature of IFLC. No adverse events >grade 2 were reported after SRS/FSRT.

CONCLUSION

CK-based SRS/FSRT is a safe and efficient option for older patients with BM arising from NSCLC, showing good OS without severe side effects. GPA, which was consisted in age, performance status, extra-cerebral metastasis, and number of BM, seemed to be predictive factors for OS.

Target volume size effect on comparison of dynamic arc treatment plans computed using flattened and unflattened 6MV beams

INTRODUCTION/BACKGROUND

In conventional linear accelerators, to obtain flat profiles leading to uniform dose distribution in homogeneous medium, the flattening filter is usually applied on the beam path. In recent years, to obtain higher dose rates, there have been the options of flattening filter free (FFF) beams and it has been noticed that these have many advantages. The aim of this study was to clearly underline the advantages and the drawbacks of flattened filter free (FFF) beams in comparison with the flattening filter (FF) beams for different clinical contexts (planning target volumes locations).

METHODS

Two groups (planned with auto-planning VMAT, full and partial arcs) of eight patients each were analyzed: Group I (small planning target volume PTV, with average volume 48.9 ±44.4 cm³), Group II (large PTV, with average volume 532.4 ±368.8 cm³). Both beam modalities 6MV and 6MVFFF were compared in terms of Dmax, D95%, D1cc, D2cc, homogeneity index (HI), number of monitor units (MU), treatment delivery time.

RESULTS

Using the 6MVFFF, the treatment delivery time was significantly reduced (p<0.05). For larger PTVs, the number of MU increased by more than twice, and the p-value shown a significant difference (p= 0.008). The value of Dmax increased by 4%. On the contrary, for small volumes, the results were quite similar from 6MVFFF to 6MV except some differences in terms of MU.

CONCLUSION

It is recommended to use 6MVFFF beam with small PTV volumes. Dose distributions are almost the same as with 6MV and there is a significant reduction of the treatment delivery time up to 57%. Due to the dose profile shape in FFF mode, the dose is lowered beyond the central axis for the FFF beams, and the additional MU allows the dose to be delivered away from the beam axis.

Management of brain metastases in elderly patients with lung cancer

The incidence of brain metastases (BM) is continuing to grow in the elderly population with lung cancer, but these patients are seriously under-represented in clinical trials. Thus, their treatment is not based on the evidence from randomized prospective studies. Age is a well recognized poor prognostic factor for survival in patients with BM from lung cancer, which is reflected in prognostic scales, but its impact on the patients' prognosis reflected by its value in gradually updated grading indices seems to decrease. The reason for poorer outcomes in the elderly is unknown—it may result from the influence of the age per se, simplified staging work-up and suboptimal treatment in this patient subgroup or the excess toxicity of the aggressive anticancer treatment secondary to the impaired physiological regulation mechanisms and comorbidities. The main goal of treatment of BM is to ameliorate neurological symptoms and delay neurological progression, with the focus on the improvement and maintenance of the patients’ quality of life. The possible treatment options for BM from lung cancer are whole-brain radiotherapy, stereotactic radiosurgery, surgery, chemotherapy, targeted therapies and best supportive care. The aim of this review is to summarize the problems related to the management of BM in elderly patients with lung cancer, to analyze the value of the above mentioned treatment options, and to provide an insight into the influence of age-related clinical factors on the patients’ outcomes.

The Role of Radiation Therapy in the Older Patient

PURPOSE OF REVIEW

Older patients represent a unique subgroup of the cancer patient population for which the role of radiation therapy (RT) requires special consideration. This review will discuss many of these considerations as well as various radiation treatment techniques in the context of a variety of disease sites.

RECENT FINDINGS

Several recent studies give insight into the management of older cancer patients considering their age, performance status, comorbid conditions, quality of life, genetics, cost, and individual goals. RT plays an evolving and pivotal role in providing optimal care for this population. Recent advances in RT technique allow for more precise treatment delivery and reduced toxicity. Studies evaluating the use of radiation therapy in breast, brain, lung, prostate, rectal, pancreatic, esophageal, and oligometastatic cancer are summarized and discussed in the context of treating the older patient population. Individual age, performance and functional status, comorbid conditions, and patients' objectives and goals should all be considered when presenting treatment options for older patients and age alone should not disqualify patients from curative intent treatments. When possible, hypofractionated courses should be utilized as outcomes are often equivalent and toxicities are reduced. In many cases, RT may be preferable to other treatment options due to decreased toxicity profile and acceptable disease control.

Efficacy and safety of CyberKnife radiosurgery in elderly patients with brain metastases: a retrospective clinical evaluation

Background

Stereotactic radiosurgery (SRS) has been increasingly applied for up to 10 brain metastases instead of whole brain radiation therapy (WBRT) to achieve local tumor control while reducing neurotoxicity. Furthermore, brain-metastasis incidence is rising due to the increasing survival of patients with cancer. Our aim was to analyze the efficacy and safety of CyberKnife (CK) radiosurgery for elderly patients.

Methods

We retrospectively identified all patients with brain metastases ≥ 65 years old treated with CK-SRS at our institution since 2011 and analyzed data of primary diseases, multimodality treatments, and local therapy effect based on imaging follow-up and treatment safety. Kaplan–Meier analysis for local progression-free interval and overall survival were performed.

Results

We identified 97 patients (233 lesions) fulfilling the criteria at the first CK-SRS. The mean age was 73.2 ± 5.8 (range: 65.0–87.0) years. Overall, 13.4% of the patients were > 80 years old. The three most frequent primary cancers were lung (40.2%), kidney (22.7%), and malignant melanoma (15.5%). In 38.5% (47/122 treatments) multiple brain metastases were treated with the CK-SRS, with up to eight lesions in one session. The median planning target volume (PTV) was 1.05 (range: 0.01–19.80) cm³. A single fraction was applied in 92.3% of the lesions with a median prescription dose of 19 (range: 12–21) Gy. The estimated overall survivals at 3-, 6-, and 12 months after SRS were 79, 55, and 23%, respectively. The estimated local tumor progression-free intervals at 6-, 12-, 24-, 36-, and 72 months after SRS were 99.2, 89.0, 67.2, 64.6, and 64.6%, respectively. Older age and female sex were predictive factors of local progression. The Karnofsky performance score remained stable in 97.9% of the patients; only one patient developed a neurological deficit after SRS of a cerebellar lesion (ataxia, CTCAE Grade 2).

Conclusions

SRS is a safe and efficient option for the treatment of elderly patients with brain metastases with good local control rates without the side effects of WBRT. Older age and female sex seem to be predictive factors of local progression. Prospective studies are warranted to clarify the role of SRS treatment for elderly patients.

Management of The Elderly Cancer Patients Complexity: The Radiation Oncology Potential

Radiation oncology has the potential to be an excellent option for the frail elderly cancer patients because of its limited systemic toxicities. It can be effective for curative, prophylactic, disease control or palliative purposes. Currently about 60% of all cancer patients undergoing active treatment at some point receive radiation treatment. However, though widely used, there are limited clinical trials strictly designed for the elderly. This paper will review the key points in the assessment and treatment of elderly cancer patient including quality of life, active life expectancy, cognitive performance, frailty, sarcopenia and how the new technologies can help to reach the key goal of maintaining autonomy and independence for the elderly cancer patient.

Single-Fractionated Stereotactic Radiosurgery for Intracranial Meningioma in Elderly Patients: 25-Year Experience at a Single Institution

BACKGROUND

Stereotactic radiosurgery (SRS) has been accepted as a therapeutic option for intracranial meningiomas; however, the detailed data on outcomes in elderly patients remain unclear.

OBJECTIVE

To delineate the efficacy of SRS for meningiomas in elderly patients.

METHODS

The outcomes of 67 patients aged ≥65 yr who underwent SRS for benign intracranial meningioma (World Health Organization grade I) between 1990 and 2014 at our institution were retrospectively analyzed. The median age was 71 yr (range, 65-83 yr), and the mean and median follow-up were 62 and 52 mo (range, 7-195 mo), respectively. Tumor margins were irradiated with a median dose of 16 Gy, and the median tumor volume was 4.9 cm3 (range, 0.7-22.9 cm3).

RESULTS

Actuarial local tumor control rates at 3, 5, and 10 yr after SRS were 92%, 86%, and 72%, respectively. Previous surgery and parasagittal/falcine location were statistically significant predictive factors for failed tumor control. Mild or moderate adverse events were noted in 9 patients. No severe adverse event was observed. A higher margin dose was significantly associated with adverse events by univariate analysis.

CONCLUSION

SRS is one of the standard therapies for meningiomas in elderly patients, providing both favorable tumor control and a low risk of adverse events under minimum invasiveness.

Prognostic grading system specifically for elderly patients with brain metastases after stereotactic radiosurgery: a 2-institution study

OBJECTIVEWith the aging of the population, increasing numbers of elderly patients with brain metastasis (BM) are undergoing stereotactic radiosurgery (SRS). Among recently reported prognostic grading indexes, only the basic score for brain metastases (BSBM) is applicable to patients 65 years or older. However, the major weakness of this system is that no BM-related factors are graded. This prompted the authors to develop a new grading system, the elderly-specific (ES)-BSBM.METHODSFor this IRB-approved, retrospective cohort study, the authors used their prospectively accumulated database comprising 3267 consecutive patients undergoing Gamma Knife SRS for BMs during the 1998-2016 period at the Mito GammaHouse. Among these 3267 patients, 1789 patients ≥ 65 years of age were studied (Yamamoto series [Y-series]). Another series of 1785 patients ≥ 65 years of age in whom Serizawa and colleagues performed Gamma Knife SRS during the same period (Serizawa series [S-series]) was used for validity testing of the ES-BSBM.RESULTSTwo factors were identified as strongly impacting longer survival after SRS by means of multivariable analysis using the Cox proportional hazard model with a stepwise selection procedure. These factors are the number of tumors (solitary vs multiple: HR 1.450, 95% CI 1.299-1.621; p < 0.0001) and cumulative tumor volume (≤ 15 cm3 vs > 15 cm3: HR 1.311, 95% CI 1.078-1.593; p = 0.0067). The new index is the addition of scores 0 and 1 for these 2 factors to the BSBM. The ES-BSBM system is based on categorization into 3 classes by adding these 2 scores to those of the original BSBM. Each ES-BSBM category has 2 possible scores. For the category ES-BSBM 4-5, the score is either 4 or 5; for ES-BSBM 2-3, the score is either 2 or 3; and for ES-BSBM 0-1, the score is either 0 or 1. In the Y-series, the median survival times (MSTs, months) after SRS were 17.5 (95% CI 15.4-19.3) in ES-BSBM 4-5, 6.9 (95% CI 6.4-7.4) in ES-BSBM 2-3, and 2.8 (95% CI 2.5-3.6) in ES-BSBM 0-1 (p < 0.0001). Also, in the S-series, MSTs were, respectively, 20.4 (95% CI 17.2-23.4), 7.9 (95% CI 7.4-8.5), and 3.2 (95% CI 2.8-3.6) (p < 0.0001). The ES-BSBM system was shown to be applicable to patients with all primary tumor types as well as to those 80 years or older.CONCLUSIONSThe authors found that the addition of the number of tumors and cumulative tumor volume as scoring factors to the BSBM system significantly improved the prognostic value of this index. The present study is strengthened by testing the ES-BSBM in a different patient group.

Stereotactic radiosurgery in elderly patients with brain metastases: comparison with non-elderly patients using database of a multi-institutional prospective observational study (JLGK0901-Elderly)

PURPOSE

Stereotactic radiosurgery (SRS) has been increasingly used for elderly patients with brain metastases (BMs). However, no studies based on a large sample size have been reported. To compare SRS treatment results between elderly and non-elderly patients, we performed a subset study of elderly patients using our prospectively-accumulated multi-institution study database (JLGK0901 Study, Lancet Oncol 15:387-395, 2014).

METHODS

During the 2009-2011 period, 1194 eligible patients undergoing gamma knife SRS alone for newly diagnosed BMs were enrolled in this study from 23 gamma knife facilities in Japan. Observation was discontinued at the end of 2013. The 1194 patients were divided into the two age groups, 693 elderly ( ≥ 65 years) and 501 non-elderly ( < 65 years) patients. Our study protocol neither set an upper age limit nor required dose de-escalation.

RESULTS

Median post-SRS survival time was significantly shorter in the elderly than in the non-elderly patient group (10.3 vs 14.3 months, HR 1.380, 95% CI 1.218-1.563, p < 0.0001). However, regarding all secondary endpoints including neurological death, neurological deterioration, SRS-related complications, leukoencephalopathy, local recurrence, newly-developed tumors, meningeal dissemination, salvage SRS, whole brain radiotherapy and surgery and decreased mini-mental state examination scores, the elderly patient group was not inferior to the non-elderly patient group. In the 693 elderly patients, there was no post-SRS median survival time difference between those with 5-10 versus 2-4 tumors (10.8 vs 8.9 months, HR 0.936, 95% CI 0.744-1.167, p = 0.5601).

CONCLUSIONS

We conclude that elderly BM patients are not unfavorable candidates for SRS alone treatment.

Linac-based radiosurgery or fractionated stereotactic radiotherapy with flattening filter-free volumetric modulated arc therapy in elderly patients : A mono-institutional experience on 110 brain metastases

AIM

The aim of this study was to analyze the feasibility and clinical results of linear accelerator (linac-)based stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (SFRT) with flattening filter-free (FFF) volumetric modulated arc therapy (VMAT) in elderly patients affected by brain metastases (BMs).

PATIENTS AND METHODS

Patients selected for the present analysis were ≥65 years old with a life expectancy of >3 months, a controlled or synchronous primary tumor, and <10 BMs with a diameter <3 cm. All patients were treated with FFF linac-based SRS/SFRT. The prescribed total dose (15-30 Gy/1-5 fractions) was based on BM size and proximity to organs at risk (OAR). Toxicity was assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.0. MedCalc v18.2 (MedCalc Software, Ostend, Belgium) was used for statistical analysis.

RESULTS

From April 2014 to December 2017, 40 elderly patients with 110 BMs were treated by FFF linac-based SRS/SFRT. With a median follow-up of 28 months (range 6-50 months), median and 1‑year overall survival were 9 months and 39%, respectively; median intracranial progression-free survival was 6 months. At the time of the analysis, local control was reported in 109/110 BMs (99.1%): 12 BMs had a complete response; 51 a partial response; 46 showed stable disease. One BM (0.9%) progressed after 2 months. BM volume (<1 cc) and higher SRS/SFRT dose correlated to treatment response (p = 0.01 and p = 0.0017, respectively). No adverse events higher than grade 2 were observed.

CONCLUSION

The present findings highlight the feasibility, safety, and effectiveness of FFF linac-based SRS/SFRT in elderly patients with BMs.

The Changing Paradigm of Radiotherapy in the Elderly Population

There is increasing awareness of the special needs for care of the elderly cancer patient. Newer precise conformal radiotherapy techniques allow the safe delivery of higher doses of radiotherapy to the target tumor while reducing the dose to surrounding critical organs. This has led to a shortening of radiotherapy protocols for both curative and palliative indications. We review these novel techniques and protocols and the published clinical studies that include elderly patients treated with these techniques. Despite the fact that the elderly are a growing significant proportion of cancer patients, and the need for radiotherapy in the elderly is expected to rise with increasing life expectancy, they are underrepresented in most clinical studies of radiotherapy, and there are few studies specifically investigating radiotherapy in the elderly. The treatment of early-stage primary lung cancer with stereotactic body radiotherapy is a prime example how new highly conformal techniques and shortened treatment protocols are changing the approach to radiotherapy in the elderly. With improved imaging and radiotherapy treatment precision, it is expected that such techniques will become increasingly used in other cancer sites. It is important for radiation oncologists to be aware of the special needs of the elderly cancer patient and in particular to assess these patients based on functional status and not only chronological age. In addition, geriatric oncologists should be aware of modern radiotherapy techniques that can be particularly appropriate for the elderly patient.

Dosimetric superiority of flattening filter free beams for single-fraction stereotactic radiosurgery in single brain metastasis

For single-fraction stereotactic radiosurgery (SRS) using linac in brain metastases, more accurate treatment delivery with higher tumor absorbed doses and lower absorbed doses to normal tissues remains an enormous challenge. The purpose of this study was to investigate the dosimetric superiority in flattening filter free beams (FFF) for volumetric modulated arc therapy (VMAT) in single brain metastasis. 68 patients with single brain metastasis were included in this study. Every patient was subjected to VMAT treatment plans using 6 MV standard flattened (FF) beams (VMAT_FF) and 6 MV FFF beams (VMAT_FFF) with single fraction doses of 20 Gy. Dosimetric evaluation was performed by analysis of target coverage, dose gradients, beam-on time (BOT), gantry speed and number of monitor units (MU). There were no differences between VMAT_FF and VMAT_FFF plans in conformity and MU. VMAT_FFF plans showed obvious superiority in homogeneity, dose gradients and efficiency. For the mean BOT, VMAT_FFF plans provided a significant decrease by 42.8% compared with VMAT_FF. By the use of FFF beams, brain irradiation was minimized with about 2% reductions in low-dose regions (about 5-10 Gy). FFF beams not only resulted in more efficiency by reducing treatment time, but also provided further brain sparing compared to traditional techniques for SRS in single brain metastasis.

Radiation therapy for older patients with brain tumors

The incidence of brain tumors in the elderly population has increased over the last few decades. Current treatment includes surgery, radiotherapy and chemotherapy, but the optimal management of older patients with brain tumors remains a matter of debate, since aggressive radiation treatments in this population may be associated with high risks of neurological toxicity and deterioration of quality of life. For such patients, a careful clinical status assessment is mandatory both for clinical decision making and for designing randomized trials to adequately evaluate the optimal combination of radiotherapy and chemotherapy.

Several randomized studies have demonstrated the efficacy and safety of chemotherapy for patients with glioblastoma or lymphoma; however, the use of radiotherapy given in association with chemotherapy or as salvage therapy remains an effective treatment option associated with survival benefit. Stereotactic techniques are increasingly used for the treatment of patients with brain metastases and benign tumors, including pituitary adenomas, meningiomas and acoustic neuromas. Although no randomized trials have proven the superiority of SRS over other radiation techniques in older patients with brain metastases or benign brain tumors, data extracted from recent randomized studies and large retrospective series suggest that SRS is an effective approach in such patients associated with survival advantages and toxicity profile similar to those observed in young adults. Future trials need to investigate the optimal radiation techniques and dose/fractionation schedules in older patients with brain tumors with regard to clinical outcomes, neurocognitive function, and quality of life.

Is upfront stereotactic radiosurgery a rational treatment option for very elderly patients with brain metastases? A retrospective analysis of 106 consecutive patients age 80 years and older

Background

Advanced age has been shown to be a factor predicting poor survival in patients with brain metastases (BM). There have been only a few studies focusing on stereotactic radiosurgery (SRS) for elderly BM patients. The present study aimed to investigate the efficacy and limitations of SRS for very elderly BM patients.

Methods

This was a retrospective observational study analyzing 106 consecutive patients (69 males/37 females) age 80 years and older who received upfront Gamma Knife SRS for BM between January 2009 and October 2015. The median age was 84 years, and the median Karnofsky performance status (KPS) was 70. Fifty-two patients had a solitary BM, and others multiple BM. The median cumulative tumor volume was 3.9 mL and the median dose prescribed was 20 Gy. Overall survival (OS), neurological death rates and distant and local intracranial tumor control rates were analyzed.

Results

No patients were lost to follow-up. Six-month and 12-month OS rates were 54% and 32%, respectively. The median OS time was 7.1 months. Competing risks analysis showed that 6-month and 12-month neurological death rates were 8% and 11%, respectively. In total, 245 / 311 tumors (79%) in 82 patients (77%) with sufficient radiological follow-up data were evaluated. Six-month and 12-month distant BM recurrence rates (per patient) after SRS were 17% and 25%, respectively. Six-month and 12-month rates of local tumor control (per lesion) were 94% and 89%, respectively. Repeat SRS, salvage WBRT and surgical resection were subsequently required in 25, 4 and 1 patient, respectively. Proportional hazard regression analysis showed that KPS ≥ 70 (HR: 0.444, P < .001), controlled primary disease/no extracranial metastases (HR: 0.361, P < .001) and female sex (HR: 0.569, P = 0.028) were independent factors predicting better OS. Similarly, tumor volume (>2 mL) was the only factor predicting a higher rate of local control failure (HR: 12.8, P = 0.003).

Conclusions

The present study suggested an upfront SRS strategy to offer a feasible and effective treatment option for very elderly patients with limited BM. In the majority of patients, neurological death could be delayed or even prevented.

Stereotactic radiosurgery for brain metastases: a case-matched study comparing treatment results for patients 80 years of age or older versus patients 65-79 years of age

OBJECT

Recently, an increasing number of patients with brain metastases, even patients over 80 years of age, have been treated with stereotactic radiosurgery (SRS). However, there is little information on SRS treatment results for patients with brain metastases 80 years of age and older. The authors undertook this study to reappraise whether SRS treatment results for patients 80 years of age or older differ from those of patients who are 65-79 years old.

METHODS

This was an institutional review board-approved, retrospective cohort study. Among 2552 consecutive brain metastasis patients who underwent SRS during the 1998-2011 period, we studied 165 who were 80 years of age or older (Group A) and 1181 who were age 65-79 years old (Group B). Because of the remarkable disproportion in patient numbers between the 2 groups and considerable differences in pre-SRS clinical factors, the authors conducted a case-matched study using the propensity score matching method. Ultimately, 330 patients (165 from each group, A and B) were selected. For time-to-event outcomes, the Kaplan-Meier method was used to estimate overall survival and competing risk analysis was used to estimate other study end points, as appropriate.

RESULTS

Although the case-matched study showed that post-SRS median survival time (MST, months) was shorter in Group A patients (5.3 months, 95% CI 3.9-7.0 months) than in Group B patients (6.9 months, 95% CI 5.0-8.1 months), this difference was not statistically significant (HR 1.147, 95% CI 0.921-1.429, p = 0.22). Incidences of neurological death and deterioration were slightly lower in Group A than in Group B patients (6.3% vs 11.8% and 8.5% vs 13.9%), but these differences did not reach statistical significance (p = 0.11 and p = 0.16). Furthermore, competing risk analyses showed that the 2 groups did not differ significantly in cumulative incidence of local recurrence (HR 0.830, 95% CI 0.268-2.573, p = 0.75), rates of repeat SRS (HR 0.738, 95% CI 0.438-1.242, p = 0.25), or incidence of SRS-related complications (HR 0.616, 95% CI 0.152-2.495, p = 0.49). Among the Group A patients, post-SRS MSTs were 11.6 months (95% CI 7.8-19.6 months), 7.9 months (95% CI 5.2-10.9 months), and 2.8 months (95% CI; 2.4-4.6 months) in patients whose disease status was modified-recursive partitioning analysis (RPA) Class(es) I+IIa, IIb, and IIc+III, respectively (p < 0.001).

CONCLUSIONS

Our results suggest that patients 80 years of age or older are not unfavorable candidates for SRS as compared with those 65-79 years old. Particularly, even among patients 80 years and older, those with modified-RPA Class I+IIa or IIb disease are considered to be favorable candidates for more aggressive treatment of brain metastases.

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

AIM

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

BACKGROUND

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Review of current best practice and priorities for research in radiation oncology for elderly patients with cancer: the International Society of Geriatric Oncology (SIOG) task force

Radiotherapy (RT) is a key component of the management of older cancer patients. Level I evidence in older patients is limited. The International Society of Geriatric Oncology (SIOG) established a task force to make recommendations for curative RT in older patients and to identify future research priorities. Evidence-based guidelines are provided for breast, lung, endometrial, prostate, rectal, pancreatic, oesophageal, head and neck, central nervous system malignancies and lymphomas. Patient selection should include comorbidity and geriatric evaluation. Advances in radiation planning and delivery improve target coverage, reduce toxicity and widen eligibility for treatment. Shorter courses of hypofractionated whole breast RT are safe and effective. Conformal RT and involved-field techniques without elective nodal irradiation have improved outcomes in non-small-cell lung cancer (NSCLC) without increasing toxicity. Where comorbidities preclude surgery, stereotactic body radiotherapy (SBRT) is an option for early-stage NSCLC and pancreatic cancer. Modern involved-field RT for lymphoma based on pre-treatment positron emission tomography data has reduced toxicity. Significant comorbidity is a relative contraindication to aggressive treatment in low-risk prostate cancer (PC). For intermediate-risk disease, 4-6 months of hormones are combined with external beam radiotherapy (EBRT). For high-risk PC, combined modality therapy (CMT) is advised. For high-intermediate risk, endometrial cancer vaginal brachytherapy is recommended. Short-course EBRT is an alternative to CMT in older patients with rectal cancer without significant comorbidities. Endorectal RT may be an option for early disease. For primary brain tumours, shorter courses of postoperative RT following maximal debulking provide equivalent survival to longer schedules. MGMT methylation status may help select older patients for temozolomide alone. Stereotactic RT provides an alternative to whole-brain RT in patients with limited brain metastases. Intensity-modulated radiation therapy provides an excellent technique to reduce dose to the carotids in head and neck cancer and improves locoregional control in oesophageal cancer. Best practice and research priorities are summarised.

Metastatic spine disease in the elderly: diagnostic and management considerations

Metastatic spine disease is becoming a more frequent problem in cancer patients as advancements in treatment for primary tumors prolong patient survival. Elderly patients over 60 years of age make up the majority of these cases, with the incidence of metastatic disease several folds higher in the elderly than in any other age group. These patients are also the most challenging group to treat, given higher rates of comorbidities and decreased tolerance to medical, surgical and radiation therapies. Advancements in therapeutic strategies, including minimally invasive surgeries and stereotactic radiosurgery, have provided increasingly attractive treatment options for elderly patients owing to their decreased procedure-associated morbidity. This article will discuss efficacy and limitations of conventional, as well as more recent, treatment modalities with an emphasis on their role in the management of elderly patients.

Stereotactic radiosurgery for brain metastases: analysis of outcome and risk of brain radionecrosis

Purpose

to investigate the factors affecting survival and toxicity in patients treated with stereotactic radiosurgery (SRS), with special attention to volumes of brain receiving a specific dose (V10 - V16 Gy) as predictors for brain radionecrosis.

Patients and Methods

Two hundred six consecutive patients with 310 cerebral metastases less than 3.5 cm were treated with SRS as primary treatment and followed prospectively at University of Rome La Sapienza Sant'Andrea Hospital. Overall survival, brain control, and local control were estimated using the Kaplan-Meier method calculated from the time of SRS. Univariate and multivariate analysis using a Cox proportional hazards regression model were performed to determine the predictive value of prognostic factors for treatment outcome and SRS-related complications.

Results

Median overall survival and brain control were 14.1 months and 10 months, respectively. The 1-year and 2-year survival rates were 58% and 24%, and respective brain control were 43% and 22%. Sixteen patients recurred locally after SRS, with 1-year and 2-year local control rates of 92% and 84%, respectively. On multivariate analysis, stable extracranial disease and KPS >70 were associated with the most significant survival benefit. Neurological complications were recorded in 27 (13%) patients. Severe neurological complications (RTOG Grade 3 and 4) occurred in 5.8% of patients. Brain radionecrosis occurred in 24% of treated lesions, being symptomatic in 10% and asymptomatic in 14%. On multivariate analysis, V10 through V16 Gy were independent risk factors for radionecrosis, with V10 Gy and V12 Gy being the most predictive (p = 0.0001). For V10 Gy >12.6 cm³ and V12 Gy >10.9 cm³ the risk of radionecrosis was 47%.

Conclusions

SRS alone represents a feasible option as initial treatment for patients with brain metastases, however a significant subset of patients may develop neurological complications. Lesions with V12 Gy >8.5 cm³ carries a risk of radionecrosis >10% and should be considered for hypofractionated stereotactic radiotherapy especially when located in/near eloquent areas.

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.

Prognostic indices for brain metastases--usefulness and challenges

BACKGROUND

This review addresses the strengths and weaknesses of 6 different prognostic indices, published since the Radiation Therapy Oncology Group (RTOG) developed and validated the widely used 3-tiered prognostic index known as recursive partitioning analysis (RPA) classes, i.e. between 1997 and 2008. In addition, other analyses of prognostic factors in groups of patients, which typically are underrepresented in large trials or databases, published in the same time period are reviewed.

METHODS

Based on a systematic literature search, studies with more than 20 patients were included. The methods and results of prognostic factor analyses were extracted and compared. The authors discuss why current data suggest a need for a more refined index than RPA.

RESULTS

So far, none of the indices has been derived from analyses of all potential prognostic factors. The 3 most recently published indices, including the RTOG's graded prognostic assessment (GPA), all expanded from the primary 3-tiered RPA system to a 4-tiered system. The authors' own data confirm the results of the RTOG GPA analysis and support further evaluation of this tool.

CONCLUSION

This review provides a basis for further refinement of the current prognostic indices by identifying open questions regarding, e.g., performance of the ideal index, evaluation of new candidate parameters, and separate analyses for different cancer types. Unusual primary tumors and their potential differences in biology or unique treatment approaches are not well represented in large pooled analyses.

Adverse radiation effects after Gamma Knife Surgery in relation to dose and volume

INTRODUCTION

The relationship between target volume and adverse radiation effects (AREs) at low prescription doses requires elucidation. The development of AREs in three series of patients treated in the Gamma Knife is analysed in relation to prescription dose and target volume.

MATERIALS AND METHODS

There were three groups. In group 1, there were of 275 patients with meningiomas; in group 2, 132 patients with vestibular schwannomas; and in group 3, 107 patients with arteriovenous malformations (AVMs). The minimum follow-up for each group was more than 24 months. All patients were followed up at six monthly intervals. The patients with tumours received a prescription dose of 12 Gy, which was varied to protect normal structures but not in relation to tumour volume per se. The desired AVM prescription dose was 25 Gy, but this was also reduced to protect normal structures and to keep the total dose within certain pre-defined limits. All AREs refer to intra-parenchymal increased perilesional T2 signal on MR irrespective of clinical correlation.

RESULTS

There was no relationship between tumour volume and the development of ARE in the tumour groups. There was a highly significant relationship between target volume and the development of ARE for the AVMs with their much higher dose. Radiation-induced clinical trigeminal and facial nerve deficits with both vestibular schwannomas and meningiomas were always associated with an increased T2 signal in the neighbouring brainstem parenchyma.

CONCLUSIONS

The relationship between target volume and the risk of adverse radiation effects may not apply with lower prescription doses. Individual radiosensitivity may explain why a minority suffer AREs unrelated to target volume. It is possible that radiation-induced brainstem parenchymal damage with concomitant cranial nerve deficits may be commoner after radiosurgery than is usually thought. If tumour control with lower doses is adequate, radiosurgery could be safely considered for larger targets associated with a high risk from microsurgery.

Can standard magnetic resonance imaging reliably distinguish recurrent tumor from radiation necrosis after radiosurgery for brain metastases? A radiographic-pathological study

OBJECTIVE

Stereotactic radiosurgery is a commonly used treatment method in the management of metastatic brain tumors. When lesions enlarge after radiosurgery, it may represent tumor regrowth, radiation necrosis, or both. The purpose of this study was to determine whether standard magnetic resonance imaging (MRI) sequences could reliably distinguish between these pathological possibilities.

METHODS

A total of 619 patients, reported in a previous study, were treated with radiosurgery for metastatic brain tumors. Of those patients, 59 underwent subsequent craniotomy for symptomatic lesion enlargement. Of those 59 patients, 32 had complete preoperative MRI studies as well as surgical pathology reports. The following MRI features were analyzed in this subset of patients: arteriovenous shunting, gyriform lesion or edema distribution, perilesional edema, cyst formation, and pattern of enhancement. A novel radiographic feature, called the lesion quotient, which is the ratio of the nodule as seen on T2 imaging to the total enhancing area on T1 imaging, was also analyzed.

RESULTS

Sensitivity, specificity, and predictive values were computed for each radiographic characteristic. Lesions containing only radiation necrosis never displayed gyriform lesion/edema distribution, marginal enhancement, or solid enhancement. All lesions exhibited perilesional edema. A lesion quotient of 0.6 or greater was seen in all cases of recurrent tumor, a lesion quotient greater than 0.3 was seen in 19 of 20 cases of combination pathology, and a lesion quotient of 0.3 or less was seen in 4 of 5 cases of radiation necrosis. The lesion quotient correlated with the percentage of tumor identified on pathological specimens.

CONCLUSION

The lesion quotient appears to reliably identify pure radiation necrosis on standard sequence MRI. Other examined radiographic features, including arteriovenous shunting, gyriform lesion/edema distribution, enhancement pattern, and cyst formation, achieved 80% or greater predictive value but had either low sensitivity or low specificity.

Stereotactic radiosurgical treatment of brain metastases in older patients

BACKGROUND

This study was designed to evaluate the therapeutic effect of stereotactic radiosurgery (SRS) in patients aged > or =75 years who presented with brain metastasis.

METHODS

The authors analyzed the data from 44 consecutive patients treated with SRS for > or =1 brain metastasis. The median age at the time of treatment for brain metastases was 79.3 years (range, 75 years-86 years), and the median Karnofsky performance status was 80 (range, 50-100). At the time of SRS, 31 patients were treated for a single metastasis, and the remaining 13 patients were treated for > or =2 lesions (n = 74 lesions). The median tumor volume was 1.2 cm(3) (range, 0.007 cm(3)-22.5 cm(3)). The median maximal and marginal doses were 36 grays (Gy) (range, 18.8 Gy-48.2 Gy) and 20 Gy (range, 10 Gy-24 Gy), respectively.

RESULTS

Median survival was 7.3 +/- 1.65 months (range, 1.6 months-38.9 months) from the time of diagnosis of brain metastasis. Median survival of the patients with a single brain metastasis (10.1 +/- 1.92 months) was longer than that of the patients with > or =2 metastases (6.6 +/- 1.28 months) (P <.02). A single lesion was found to be an independent favorable prognostic factor (P +/- = +/- .017; odds ratio, 2.385 [95% confidence interval, 1.167-4.874]) in univariate and multivariate analysis. Patients with nonsmall cell lung cancer fared worse than patients with other tumor types (survival of 6.5 +/- 0.70 months vs 10.1 +/- 2.33 months [P<.05]).

CONCLUSIONS

SRS for patients aged > or =75 years with brain metastases is an effective and safe treatment modality that appears to improve survival, with outcomes that compare favorably with those reported for younger patients in an appropriately selected population.

Treatment of central nervous system metastases: parenchymal, epidural, and leptomeningeal

PURPOSE OF REVIEW

With prolonged survival from systemic therapies in the adjuvant and salvage setting, and because these agents cannot cross the intact blood-brain barrier, central nervous system metastases are becoming a therapeutic challenge in oncology.

RECENT FINDINGS

Recent therapeutic achievements include an extended use of surgery and radiosurgery. Although each of these treatment modalities has its own indications, in patients eligible for both treatments the upfront comparison of these two techniques has not been performed yet. Systemic chemotherapies and biotherapies may be effective in the management of central nervous system metastases as they may act on both neurologic and extra-central nervous system lesions. In the treatment of epidural metastases, a surgical procedure providing immediate direct circumferential decompression of the spinal cord followed by local irradiation has been demonstrated in a prospective randomized trial. The management of leptomeningeal metastases remains controversial and of limited efficacy especially in chemoresistant tumours and still relies on the combination of chemotherapy (intrathecal and intravenous) and focal radiotherapy.

SUMMARY

Aggressive treatments in patients with early diagnosis and in whom central nervous system metastases are the life-threatening location may provide a substantial increase in survival and favourably affect quality of life.