Prolonged survival in a subgroup of patients with brain metastases treated by gamma knife surgery

[Overall survival and intracranial relapse in patients with brain metastases after gamma knife radiosurgery alone]

The study purpose was to evaluate the impact of gamma knife radiosurgery (GKRS) alone on the overall survival and rate of intracranial recurrences in brain metastasis patients.

MATERIAL AND METHODS

Treatment outcomes in 502 patients (211 males and 291 females with 2782 brain metastases (BMs)) were retrospectively reviewed. Most patients (n=142; 28.2%) were diagnosed with breast cancer. Multiple BMs were detected in 259 patients (51.6%). The median of the total tumor volume and ВM number was 5.9 cm3 (0.09-44.5 cm3) and 4 (1-36), respectively. The mean marginal radiation dose was 21 Gy (15-24 Gy). The mean follow-up period was 10.6 months (0.2-47.2 months).

RESULTS

The overall survival rate for 12 and 24 months was 37.6 and 19.1%, respectively. The median overall survival after GKRS was 8.6 months (95% confidence interval (CI) 7.0-10.0). Local control of metastatic lesions was achieved in 78.8% of patients. The median local recurrence-free survival was 6.8 months after radiosurgery. The development of new (distant) metastases was observed in 49.5% of patients. The median distant metastasis-free time was 8.8 months. The Karnofsky performance score (KPS) of ≥80 (HR 0.3935, 95% CI 0.2429-0.6376; p=0.0002), BM number of <3 (HR 0.6138, 95% CI 0.3993-0.9943; p=0.0269), and BMs of breast and lung cancers (HR 0.5442, 95% CI 0.3642-0.8071; p=0.0027) are predictors of better survival. In the case of intracranial metastasis recurrence, repeated radiosurgery provides the median overall survival of 19.6 months versus 9.6 months in patients without radiosurgery (HR 0.4026, 95% CI 0.2381-0.6809).

CONCLUSION

Radiosurgical treatment of patients with multiple BMs provides the median overall survival of 8.6 months. A good functional status, non-extensive metastasis of the brain, and radiosensitive morphology of the primary tumor are the predictors of better survival. Repeated radiosurgical treatment for intracranial recurrences provides longer overall survival compared to that in patients without repeated radiosurgical treatment.

Radiographic response of brain metastasis after linear accelerator radiosurgery

BACKGROUND

Radiographic response of brain metastasis to stereotactic radiosurgery (SRS) over time has not been well characterized. Being able to predict SRS-induced changes in tumor size over time may allow improved counseling of patients and potentially earlier recognition of poor response to SRS.

OBJECTIVE

To quantify the rate of change in size of metastatic brain tumors after treatment with a linear accelerator (LINAC) SRS.

METHODS

We performed a retrospective analysis of patients with single metastatic brain tumors treated with LINAC SRS at the University of Florida between 1992 and 2009 who had at least one MRI after treatment. A total of 218 patients with 406 follow-up MRI scans were included in the study. Tumor area was calculated by measuring the largest tumor area on axial imaging and using the equation for area of an ellipse. Primary outcome was percent change in tumor size. The contribution of several factors including gender, primary tumor histology, synchronous or asynchronous presentation, prior treatment, primary tumor control, and SRS dose were examined using multivariate analysis.

RESULTS

Mean patient age was 58.3 years (range 4-86), and 48.6% of patients were female. Sixty-three percent of patients had primary tumor control and 70.6% had asynchronous presentation of their brain metastases. SRS peripheral dose range was 1,000-2,250 cGy with a median of 1,750 cGy. The mean percent size change was -22.6% with a mean rate of change of -7.0% per month. The median percent change was -49.7% with a median rate of change of -8.8% per month. The median follow-up was 4.8 months (range 0.3-52.5). Female gender and melanoma histology were found to be significant predictors of an increase in tumor size. Lack of previous surgical resection was a significant predictor of a decrease in tumor size after SRS. Other factors tested with multivariate analysis, including age, synchronicity of presentation, dose, dose volume, Karnofsky performance score, and primary tumor control, were not significant in predicting tumor size change after SRS.

CONCLUSION

In this study, brain metastases decreased in size by a median of 50% for a median follow-up of 4.8 months after SRS. The overall rate of decrease was 9% per month after treatment with SRS. Melanoma histology was a predictor of poor tumor control.

Surgical treatment of cerebellar metastases

BACKGROUND

Cerebral metastases are a common neurosurgical finding. Surgery confers several advantages to other therapies, including immediate symptomatic improvement, diagnosis, and relief from corticosteroid dependence. Here we evaluate patients with cerebellar metastases who underwent surgery and compare their findings to those in the literature, and address the benefit of avoiding ventriculo-peritoneal shunting in patients undergoing surgery.

METHODS

We performed a retrospective analysis involving 50 patients with cerebellar metastases who underwent surgical resection. Ventriculo-peritoneal shunts were placed in patients necessitating permanent CSF drainage. We evaluated presentation, diagnosis, complications, and outcome.

RESULTS

Our review included 21 males and 29 females, 29 to 82 years of age. Primary tumors included lung (48%), breast (14%), GI (14%), endometrial/ovarian (6%), melanoma (6%), sarcoma (4%), lymphoma (4%), laryngeal (2%), and other (2%). Clinical symptoms at presentation commonly were those secondary to elevated intracranial pressure and were the initial complaint in 34% of patients. Preoperatively, 29 patients were noted to have hydrocephalus. Importantly, 76% of these patients were able to avoid placement of a ventriculo-peritoneal shunt following surgery. Only two complications were noted in our series of 50 patients, including a symptomatic pseudomeningocele and a wound infection. No symptomatic postoperative hematoma developed in any surgical case.

CONCLUSION

A review of the literature has shown a high complication rate in patients undergoing surgical resection of cerebellar metastases. We have shown that surgical resection of cerebellar metastases is a safe procedure and is effective in the treatment of hydrocephalus in the majority of patients harboring cerebellar lesions.

Palliative stereotactic-endoscopic third ventriculostomy for the treatment of obstructive hydrocephalus from cerebral metastasis

BACKGROUND

Endoscopic third ventriculostomy (ETV) is increasingly used in the treatment of obstructive hydrocephalus. The literature supporting its use in the setting of metastatic disease, however, remains limited.

METHODS

Between 2005 and 2010, 16 patients underwent ETV for treatment of obstructive hydrocephalus secondary to cerebral metastasis. Efficacy of symptomatic palliation and associated complications were reviewed. The results were compared to reported data for ventriculoperitoneal shunt placement in adult brain tumor patients. Patient selection criteria for ETV are reviewed.

RESULTS

Eleven of the 16 patients experienced symptomatic improvement after ETV (69%). Patients who presented with headache associated with nausea, vomiting, or lethargy were more likely to respond to treatment relative to patients presenting with headache alone. Of the 16 ETV patients, one suffered a wound infection and another underwent external ventricular drainage for assessment of intracranial pressure, yielding an overall complication rate of 12.5%.

CONCLUSIONS

In select patients with obstructive hydrocephalus related to cerebral metastasis, ETV constitutes a minimally invasive palliative option. The efficacy of ETV in this population is comparable to those reported for obstructive hydrocephalus secondary to primary cerebral neoplasm or other non-neoplastic causes. Patients receiving chemotherapy close to the time of ETV may be at increased risk for infection.

Combined surgical resection and stereotactic radiosurgery for treatment of cerebral metastases

BACKGROUND

Patients with limited intracranial metastatic disease traditionally have been treated with surgery followed by WBRT. However, there is growing concern for the debilitating cognitive effects after WBRT in long-term survivors. We present a series of patients treated with surgery followed by SRS, while reserving WBRT as a salvage therapy for disease progression.

METHODS

Medical records from 15 patients with 1 to 2 cerebral metastases who underwent both resection and SRS were reviewed. Outcome measures included overall survival, survival by RPA class, EOR, local tumor control, progression of intracranial disease, need for WBRT salvage therapy, and COD.

RESULTS

Fifteen patients with cerebral metastases were treated with the combined surgery-SRS paradigm. Eight of the 15 patients (53.3%) were designated RPA class 1, with 6 of 15 (40.0%) in class 2 and 1 of 15 (6.7%) in class 3. Gross total resection was achieved in 12 cases (80.0%). Overall median survival was 20.0 months, with values of 22.0 and 13.0 months for RPA classes 1 and 2, respectively. Local recurrence occurred in 16.7% of those patients with GTR. Six patients (40.0%) went on to receive WBRT at a median of 8.0 months from initial presentation. Twelve patients (80.0%) had died at the completion of the study, and the COD was CNS progression in 33.3%.

CONCLUSIONS

Surgical resection combined with SRS is an effective treatment for selected patients with limited cerebral metastatic disease. Survival using this combined treatment was equivalent to or greater than that reported by other studies using surgery + WBRT or SRS + WBRT.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Therapeutic management of brain metastasis

This review focuses on the management of brain metastases. The four main modes of therapy are discussed: whole brain radiation therapy (WBRT), surgery, radiosurgery, and chemotherapy. Young patients with limited extracranial disease may benefit from surgical resection of a single brain metastasis, and from radiosurgery (or stereotactic radiotherapy) if two to four brain metastases are present. Whether WBRT after surgery or radiosurgery is beneficial is uncertain. Therefore, two approaches can be justified in patients with a good prognosis: WBRT after surgery or radiosurgery, or alternatively, observation with MRI follow-up after surgery or radiosurgery. A hyperfractionated radiation scheme is then to be preferred to limit late toxicity of WBRT. Patients with extensive extracranial tumour activity or impaired quality of life may benefit from radiosurgery (one to four brain metastases), or from shorter WBRT schedules. We propose a decision tree on the various ways to treat brain metastasis.