Preservation of neurocognitive function and local control of 1 to 3 brain metastases treated with surgery and carmustine wafers

"Non-Eloquent" brain regions predict neuropsychological outcome in tumor patients undergoing awake craniotomy

Supratotal resection of primary brain tumors is being advocated especially when involving "non-eloquent" tissue. However, there is extensive neuropsychological data implicating functions critical to higher cognition in areas considered "non-eloquent" by most surgeons. The goal of the study was to determine pre-surgical brain regions that would be predictive of cognitive outcome at 4-6 months post-surgery. Cortical reconstruction and volumetric segmentation were performed with the FreeSurfer-v6.0 image analysis suite. Linear regression models were used to regress cortical volumes from both hemispheres, against the total cognitive z-score to determine the relationship between brain structure and broad cognitive functioning while controlling for age, sex, and total segmented brain volume. We identified 62 consecutive patients who underwent planned awake resections of primary (n = 55, 88%) and metastatic at the University of New Mexico Hospital between 2015 and 2019. Of those, 42 (23 males, 25 left hemispheric lesions) had complete pre and post-op neuropsychological data available and were included in this study. Overall, total neuropsychological functioning was somewhat worse (p = 0.09) at post-operative neuropsychological outcome (Mean = -.20) than at baseline (Mean = .00). Patients with radiation following resection (n = 32) performed marginally worse (p = .036). We found that several discrete brain volumes obtained pre-surgery predicted neuropsychological outcome post-resection. For the total sample, these volumes included: left fusiform, right lateral orbital frontal, right post central, and right paracentral regions. Regardless of lesion lateralization, volumes within the right frontal lobe, and specifically right orbitofrontal cortex, predicted neuropsychological difference scores. The current study highlights the gaps in our current understanding of brain eloquence. We hypothesize that the volume of tissue within the right lateral orbital frontal lobe represents important cognitive reserve capacity in patients undergoing tumor surgery. Our data also cautions the neurosurgeon when considering supratotal resections of tumors that do not extend into areas considered "non-eloquent" by current standards.

Treatment for Brain Metastases: ASCO-SNO-ASTRO Guideline

PURPOSE

To provide guidance to clinicians regarding therapy for patients with brain metastases from solid tumors.

METHODS

ASCO convened an Expert Panel and conducted a systematic review of the literature.

RESULTS

Thirty-two randomized trials published in 2008 or later met eligibility criteria and form the primary evidentiary base.

RECOMMENDATIONS

Surgery is a reasonable option for patients with brain metastases. Patients with large tumors with mass effect are more likely to benefit than those with multiple brain metastases and/or uncontrolled systemic disease. Patients with symptomatic brain metastases should receive local therapy regardless of the systemic therapy used. For patients with asymptomatic brain metastases, local therapy should not be deferred unless deferral is specifically recommended in this guideline. The decision to defer local therapy should be based on a multidisciplinary discussion of the potential benefits and harms that the patient may experience. Several regimens were recommended for non-small-cell lung cancer, breast cancer, and melanoma. For patients with asymptomatic brain metastases and no systemic therapy options, stereotactic radiosurgery (SRS) alone should be offered to patients with one to four unresected brain metastases, excluding small-cell lung carcinoma. SRS alone to the surgical cavity should be offered to patients with one to two resected brain metastases. SRS, whole brain radiation therapy, or their combination are reasonable options for other patients. Memantine and hippocampal avoidance should be offered to patients who receive whole brain radiation therapy and have no hippocampal lesions and 4 months or more expected survival. Patients with asymptomatic brain metastases with either Karnofsky Performance Status ≤ 50 or Karnofsky Performance Status < 70 with no systemic therapy options do not derive benefit from radiation therapy.Additional information is available at www.asco.org/neurooncology-guidelines.

Prospective memory and brain metastases: a relevant target for rehabilitation in post-operative patients?

PURPOSE

The study investigated the prospective memory (PM) functioning among patients with brain metastases (BM), eligible for neurosurgy/radiosurgery, and its relationships with depression and quality of life (QoL).

METHODS

This case-healthy-control, cross-sectional study, comprised 160 participants, including 49 patients with BM from various cancers treated with neurosurgery or radiosurgery. They were compared with 111 matched controls on a set of neuropsychological tests, including the MoCA global cognitive test and an experimental PM task 'PROMESSE'. Participants also completed a depression scale (BDI-II), a generic (SF-12) and a specific (QLQ-C30) QoL instrument for cancer patients. Multivariate analyses were conducted on various PM outcomes, in particular on event-based (EBPM) and time-based (TBPM) PM performances.

RESULTS

After adjusting for age and socio-cultural level, patients with BM performed worse than the control on the PM task (p < .0001) [OR 1.05; 95%CI (1.01-1.08)], whatever the location of BM (frontal versus temporal lobe). Patients with infratentorial BM exhibited better TBPM performances than patients with supratentorial BM (p = .02). The global PM performance was positively correlated with the MoCA (r = .45) and the SF-12 global score (r = .34), and negatively with the BDI-II score (r = - .20), the number of BM (r = - .34) and the volumetric of the BM (r = - 29). The TBPM performance was linked to the global QoL (r = .40) in patients.

CONCLUSION

The study showed a significant PM deficit in patients with BM eligible for a neurosurgy/radiosurgery, which is linked to damaged QoL and which likely maintains some depressive affects. Prospective memory rehabilitation program should especially focus on TBPM for post-operative patients with BM.

Neurocognitive Function in Adult Cancer Patients

Impaired neurocognitive function is an increasingly recognized morbidity in patients who have cancer. Cancer treatments, psychosocial stressors, and the malignancy itself can alter brain function. The mechanisms by which this occurs are under active investigation. Although there is a growing appreciation of its prevalence and causes, there remain limited therapeutic options for the treatment of neurocognitive dysfunction in this population. A persistent scientific and clinical effort to understand its mechanisms and impact is critical to the care of oncology patients.

Impact of Cognitive Impairment in Patients with Gliomas

OBJECTIVES

To address the estimated rates of incidence, potential underlying etiologies, and cognitive domains affected from diagnosis and treatment. To describe potential cognitive function interventions.

DATA SOURCES

PubMed.

CONCLUSION

Adults with gliomas report that the most distressing, persistent, and greatest negative impact on their lives relates to the cognitive impairment they experience. However, there are several potential interventions that may prevent cognitive decline during treatment or maintain cognitive function long term.

IMPLICATIONS FOR NURSING PRACTICE

Awareness of cognitive sequela that adults with gliomas face can lead to early identification, full neurocognitive profiling, and implementation of evidence-based interventions for those experiencing cognitive impairments following cancer treatment.

The Survival Advantage of "Supratotal" Resection of Glioblastoma Using Selective Cortical Mapping and the Subpial Technique

BACKGROUND

A substantial body of evidence suggests that cytoreductive surgery is a prerequisite to prolonging survival in patients with glioblastoma (GBM).

OBJECTIVE

To evaluate the safety and impact of "supratotal" resections beyond the zone of enhancement seen on magnetic resonance imaging scans, using a subpial technique.

METHODS

We retrospectively evaluated 86 consecutive patients with primary GBM, managed by the senior author, using a subpial resection technique with or without carmustine (BCNU) wafer implantation. Multivariate Cox proportional hazards regression was used to analyze clinical, radiological, and outcome variables. Overall impacts of extent of resection (EOR) and BCNU wafer placement were compared using Kaplan-Meier survival analysis.

RESULTS

Mean patient age was 56 years. The median OS for the group was 18.1 months. Median OS for patients undergoing gross total, near-total, and subtotal resection were 54, 16.5, and 13.2 months, respectively. Patients undergoing near-total resection ( P = .05) or gross total resection ( P < .01) experienced statistically significant longer survival time than patients undergoing subtotal resection as well as patients undergoing ≥95% EOR ( P < .01) when compared to <95% EOR. The addition of BCNU wafers had no survival advantage.

CONCLUSIONS

The subpial technique extends the resection beyond the contrast enhancement and is associated with an overall survival beyond that seen in similar series where resection of the enhancement portion is performed. The effect of supratotal resection on survival exceeded the effects of age, Karnofsky performance score, and tumor volume. A prospective study would help to quantify the impact of the subpial technique on quality of life and survival as compared to a traditional resection limited to the enhancing tumor.

Neurocognitive aspects of brain metastasis

Brain metastases are common, occurring in approximately 20% of cancer patients. One of the biggest concerns for these patients and their families is neurocognitive decline. Neurocognitive issues in this patient population are complex and many patients have neurocognitive impairment due to systemic therapies even before they develop brain metastases. The development of brain metastases as well as the treatment of these tumors can cause decline in neurocognitive function. Diffuse treatments such as whole-brain radiotherapy are more frequently associated with neurocognitive decline than focal interventions such as radiosurgery, surgical resection, and implantable chemotherapy wafers. For patients with brain metastases treatment decisions require a multidisciplinary approach, balancing many factors including the neurocognitive impact of treatment and the disease process itself. Finally, to continue to advance the field there needs to be continued utilization, both off and on clinical trial, of performance-based clinical outcome assessments (i.e., neurocognitive tests) to objectively assess and measure the neurocognitive outcomes of these patients.

Individualized Map of White Matter Pathways: Connectivity-Based Paradigm for Neurosurgical Planning

BACKGROUND

Advances in white matter tractography enhance neurosurgical planning and glioma resection, but white matter tractography is limited by biological variables such as edema, mass effect, and tract infiltration or selection biases related to regions of interest or fractional anisotropy values.

OBJECTIVE

To provide an automated tract identification paradigm that corrects for artifacts created by tumor edema and infiltration and provides a consistent, accurate method of fiber bundle identification.

METHODS

An automated tract identification paradigm was developed and evaluated for glioma surgery. A fiber bundle atlas was generated from 6 healthy participants. Fibers of a test set (including 3 healthy participants and 10 patients with brain tumors) were clustered adaptively with this atlas. Reliability of the identified tracts in both groups was assessed by comparison with 2 experts with the Cohen κ used to quantify concurrence. We evaluated 6 major fiber bundles: cingulum bundle, fornix, uncinate fasciculus, arcuate fasciculus, inferior fronto-occipital fasciculus, and inferior longitudinal fasciculus, the last 3 tracts mediating language function.

RESULTS

The automated paradigm demonstrated a reliable and practical method to identify white mater tracts, despite mass effect, edema, and tract infiltration. When the tumor demonstrated significant mass effect or shift, the automated approach was useful for providing an initialization to guide the expert with identification of the specific tract of interest.

CONCLUSION

We report a reliable paradigm for the automated identification of white matter pathways in patients with gliomas. This approach should enhance the neurosurgical objective of maximal safe resections.

ABBREVIATIONS

AF, arcuate fasciculusDTI, diffusion tensor imagingIFOF, inferior fronto-occipital fasciculusILF, inferior longitudinal fasciculusROI, region of interestWM, white matter.

Imaging the DNA Alkylator Melphalan by CEST MRI: An Advanced Approach to Theranostics

Brain tumors are among the most lethal types of tumors. Therapeutic response variability and failure in patients have been attributed to several factors, including inadequate drug delivery to tumors due to the blood-brain barrier (BBB). Consequently, drug delivery strategies are being developed for the local and targeted delivery of drugs to brain tumors. These drug delivery strategies could benefit from new approaches to monitor the delivery of drugs to tumors. Here, we evaluated the feasibility of imaging 4-[bis(2-chloroethyl)amino]-l-phenylalanine (melphalan), a clinically used DNA alkylating agent, using chemical exchange saturation transfer magnetic resonance imaging (CEST MRI), for theranostic applications. We evaluated the physicochemical parameters that affect melphalan's CEST contrast and demonstrated the feasibility of imaging the unmodified drug by saturating its exchangeable amine protons. Melphalan generated a CEST signal despite its reactivity in an aqueous milieu. The maximum CEST signal was observed at pH 6.2. This CEST contrast trend was then used to monitor therapeutic responses to melphalan in vitro. Upon cell death, the decrease in cellular pH from ∼7.4 to ∼6.4 caused an amplification of the melphalan CEST signal. This is contrary to what has been reported for other CEST contrast agents used for imaging cell death, where a decrease in the cellular pH following cell death results in a decrease in the CEST signal. Ultimately, this method could be used to noninvasively monitor melphalan delivery to brain tumors and also to validate therapeutic responses to melphalan clinically.

The Efficacy of Postoperative Chemotherapy for Patients with Metastatic Brain Tumors from Non-Small Cell Lung Cancer

BACKGROUND

The purpose of this study is to evaluate the effect of postoperative chemotherapy on recurrence and survival in patients after resection of metastatic brain tumors from non-small cell lung cancers.

METHODS

Patients who went through resection of a single metastatic brain tumor from non-small cell lung cancer from July 2001 to December 2012 were reviewed. Those selected were 77 patients who survived more than 3 months after surgery were selected. Among them, 44 patients received various postoperative systemic chemotherapies, 33 patients received postoperative adjuvant whole brain radiotherapy (WBRT). Local/distant recurrence rate, local/distant recurrence free survival, disease free survival (DFS), and overall survival were compared between the two groups.

RESULTS

Among the 77 patients, there were 19 (24.7%) local recurrences. Local recurrence occurred in 7 (21.2%) of 33 patients in the adjuvant radiotherapy (RT) group and in 12 (27.3%) of the 44 patients in the chemotherapy group (p=0.542). Among the 77 patients, there were 34 (44.1%) distant recurrences. Distant recurrence occurred in 7 (21.2%) of the 33 patients in the adjuvant RT group and in 27 (61.4%) of the 44 patients in the chemotherapy group (p<0.0005). Patients' survival in terms of local recurrence free survival, distant recurrence free survival, DFS, and overall survival was not shown to be statistically different between the two groups before and after adjusting for covariates.

CONCLUSION

There was no significant difference observed between postoperative adjuvant chemotherapy and adjuvant WBRT in terms of patients' survival. Postoperative chemotherapy is more feasible and may be an appropriate option for simultaneous control of both primary and metastatic lesions.

Tumor progression in patients receiving adjuvant whole-brain radiotherapy vs localized radiotherapy after surgical resection of brain metastases

BACKGROUND

Surgery followed by adjuvant radiotherapy is a well-established treatment paradigm for brain metastases.

OBJECTIVE

To examine the effect of postsurgical whole-brain radiotherapy (WBRT) or localized radiotherapy (LRT), including stereotactic radiosurgery and intraoperative radiotherapy, on the rate of recurrence both local and distal to the resection site in the treatment of brain metastases.

METHODS

We retrospectively identified patients who underwent surgery for brain metastasis at the Cleveland Clinic between 2004 and 2012. Institutional review board-approved chart review was conducted, and patients who had radiation before surgery, who had nonmetastatic lesions, or who lacked postadjuvant imaging were excluded.

RESULTS

The final analysis included 212 patients. One hundred fifty-six patients received WBRT, 37 received stereotactic radiosurgery only, and 19 received intraoperative radiotherapy. One hundred forty-six patients were deceased, of whom 60 (41%) died with no evidence of recurrence. Competing risks methodology was used to test the association between adjuvant modality and progression. Multivariable analysis revealed no significant difference in the rate of recurrence at the resection site (hazard ratio [HR] 1.46, P = .26) or of unresected, radiotherapy-treated lesions (HR 1.70, P = .41) for LRT vs WBRT. Patients treated with LRT had an increased hazard of the development of new lesions (HR 2.41, P < .001) and leptomeningeal disease (HR 2.45, P = .04). Median survival was 16.5 months and was not significantly different between groups.

CONCLUSION

LRT as adjuvant treatment to surgical resection of brain metastases is associated with an increased rate of development of new distant metastases and leptomeningeal disease compared with WBRT, but not with recurrence at the resection site or of unresected lesions treated with radiation.