An Exploratory Analysis of the Conditional Neurocognitive Function Failure Risk in Patients Receiving Whole Brain Radiotherapy for Brain Metastases on NRG Oncology CC001: Conditional Neurocognitive Toxicity Risk.

PURPOSE: We sought to estimate the conditional risk of development of neurocognitive function failure (NCFF) after whole brain radiotherapy (WBRT) for patients with brain metastases (BM) on NRG Oncology CC001. In addition, we aimed to determine if factors prognostic of NCFF at time of treatment remained relevant over time. MATERIALS/METHODS: We performed a post hoc analysis of 518 patients enrolled on NRG CC001 in which patients with BM were randomly assigned to WBRT + memantine or hippocampal-avoidant (HA-WBRT) + memantine. Life table method was used to calculate conditional monthly hazard rates and cumulative incidence was used to estimate rates of NCFF. Risk factors associated with NCFF were analyzed using cause-specific multivariable Cox proportional hazards modeling. RESULTS: The cumulative risk of development of NCFF by 6 months was 64.0% for the entire cohort. The greatest conditional monthly hazard rate of development of neurocognitive toxicity was 2-3 months post radiation (0.97, 95% CI 0.85-1.10); this rate significantly declined and then plateaued to 0.036 (95% CI: 0-0.11) by 8 months post treatment. For 2-month survivorship without cognitive failure, HA-WBRT (HR 0.74, P=0.033) and age ≤ 61 (HR 0.62, P=0.003) continued to be protective against cognitive toxicity. In addition, conditional cumulative incidence of development of NCFF was significantly reduced with HA techniques for patients living ≥ 2 months free of cognitive dysfunction (P=0.047). CONCLUSIONS: Our data highlight that the greatest risk for development of neurocognitive toxicity is within the first 3 months after treatment, and therefore strategies to mitigate toxicities should focus on this initial period. Moreover, the conditional risk of neurocognitive impairment significantly declines the longer patients live with preserved cognition. Importantly, these data can be used to inform patients on how their risks of development of NCFF can change over time.

Evaluating the sensitivity of EQ-5D-5L in patients with brain metastases: a secondary analysis of NRG CC001.

BACKGROUND: EuroQoL EQ-5D-5L is a commonly used measure of health-related quality of life in clinical trials given the use of its index score as a measure of health utilities. It is unclear whether EQ-5D-5L is sensitive to changes in neurocognitive function and progression that occur following brain radiation. This study sought to evaluate the sensitivity of EQ-5D-5L in reflecting these changes. METHODS: A secondary analysis of NRG Oncology CC001 was performed. Mean EQ-5D-5L index and visual analog scale (VAS) score changes from baseline between groups of patients stratified by neurocognitive function and intracranial progression status were assessed. MD Anderson Symptom Inventory for brain tumor (MDASI-BT) symptom and interference items were also analyzed between groups. RESULTS: EQ-5D-5L mean index and VAS score changes between patients who had cognitive failure and those who had preserved cognition showed no statistically significant differences at any timepoint. In contrast, VAS changes at 4 months (1.61 vs -5.13, P = .05) and 6 months (8.17 vs -0.14, P = .04) were significantly improved in the patients who survived without intracranial progression. MDASI-BT cognitive factor scores were improved in the cohort of patients with preserved neurocognitive function at 2 months (1.68 vs 2.08, P = .05) and 4 months (1.35 vs 1.83, P = .04). MDASI-BT symptom interference was significantly associated with intracranial progression at 4 months, but not with neurocognitive status. CONCLUSION: EQ-5D-5L index and VAS scores were not sensitive to neurocognitive changes that patients experienced, but VAS scores were sensitive to progression. This study challenges the routine use of EQ-5D as a quality of life metric in brain metastases clinical trials that are focused on preventing neurocognitive dysfunction. TRIAL REGISTRATION: NCT# 02360215.

Evaluating the Heterogeneity of Hippocampal Avoidant Whole Brain Radiotherapy Treatment Effect: A Secondary Analysis of NRG CC001.

BACKGROUND: Hippocampal avoidant whole brain radiotherapy (HA-WBRT) is the standard of care for patients needing WBRT for brain metastases (BM). This study, using existing data from NRG Oncology CC001 including baseline tumor characteristics and patient-reported MD Anderson Symptom Inventory-Brain Tumor (MDASI-BT) scores, sought to identify subgroups of patients that demonstrate differential neuroprotective treatment response to HA-WBRT. METHODS: An exploratory analysis of NRG CC001, a phase III trial in which 518 patients were randomly assigned to WBRT plus memantine or HA-WBRT plus memantine, was performed. Rates of neurocognitive function failure (NCFF) were estimated between subgroups and stratified by arm. Covariate and subgroup interaction with differential treatment response were calculated. RESULTS: The benefit of HA-WBRT on decreasing NCFF was seen in patients living ≥ 4 months (HR 0.75, 95% CI: 0.58-0.97, P=0.03), whereas patients living < 4 months derived no significant neurocognitive benefit. Significant association between baseline MDASI-BT cognitive factor and treatment response (interaction P=0.03) was identified. Patients with lower MDASI-BT scores (less patient-reported cognitive impairment) derived significantly greater benefit (HR=0.64, 95% CI: 0.48-0.85, P=0.002) compared to those with highest MDASI-BT scores (HR=1.24, 95% CI: 0.76-2.04, P=0.39). Tumor histology also had significant interaction (P=0.01) with treatment response. Primary lung histology patients derived cognitive failure risk reduction (HR=0.58, 95% CI: 0.43-0.77, P=0.0007) from HA-WBRT, in contrast to non-lung primary histology patients (HR=1.15, 95% CI: 0.78-1.50, P=0.48). CONCLUSIONS: Differential neuroprotective response to HA-WBRT was identified in this analysis. Patients surviving ≥ 4 months derived benefit from HA-WBRT. There is evidence of heterogeneity of treatment effect for patients with less severe patient-reported cognitive impairment at baseline and those with primary lung histology.

Pharmacogenetics of sodium-glucose co-transporter-2 inhibitors: Validation of a sex-agnostic pharmacodynamic biomarker.

AIM: To validate pharmacodynamic responses to sodium-glucose co-transporter-2 (SGLT2) inhibitors and test for association with genetic variants in SLC5A4, SLC5A9, and SLC2A9. METHODS: Canagliflozin (300 mg), a SGLT2 inhibitor, was administered to 30 healthy volunteers. Several endpoints were measured to assess clinically relevant responses, including drug-induced increases in urinary excretion of glucose, sodium and uric acid. RESULTS: This pilot study confirmed that canagliflozin (300 mg) triggered acute changes in mean levels of several biomarkers: fasting plasma glucose (-4.1 mg/dL; P = 6 × 10-5 ), serum creatinine (+0.05 mg/dL; P = 8 × 10-4 ) and serum uric acid (-0.90 mg/dL; P = 5 × 10-10 ). The effects of sex on glucosuria depended upon how data were normalized. Whereas males' responses were ~60% greater when data were normalized to body surface area, males and females exhibited similar responses when glucosuria was expressed as grams of urinary glucose per gram-creatinine. The magnitude of glucosuria was not significantly correlated with fasting plasma glucose, estimated glomerular filtration rate or age in those healthy individuals without diabetes with an estimated glomerular filtration rate of more than 60 mL/min/1.73m2 . CONCLUSIONS: Normalizing data relative to creatinine excretion will facilitate including data from males and females in a single analysis. Furthermore, because our ongoing pharmacogenomic study (NCT02891954) is conducted in healthy individuals, this will facilitate detection of genetic associations with limited confounding by other factors such as HbA1c and renal function.

Pharmacogenetics of SGLT2 Inhibitors: Validation of a sex-agnostic pharmacodynamic biomarker.

Aim: SGLT2 inhibitors provide multiple benefits to patients with type 2 diabetes - including improved glycemic control and decreased risks of cardiorenal disease. Because drug responses vary among individuals, we initiated investigations to identify genetic variants associated with the magnitude of drug responses. Methods: Canagliflozin (300 mg) was administered to 30 healthy volunteers. Several endpoints were measured to assess clinically relevant responses - including drug-induced increases in urinary excretion of glucose, sodium, and uric acid. Results: This pilot study confirmed that canagliflozin (300 mg) triggered acute changes in mean levels of several biomarkers: fasting plasma glucose (-4.1 mg/dL; p=6x10), serum creatinine (+0.05 mg/dL; p=8×10 -4 ), and serum uric acid (-0.90 mg/dL; p=5×10 -10 ). The effects of sex on glucosuria depended upon how data were normalized. Whereas males' responses were ∼60% greater when data were normalized to body surface area, males and females exhibited similar responses when glucosuria was expressed as grams of urinary glucose per gram-creatinine. The magnitude of glucosuria was not significantly correlated with fasting plasma glucose, estimated GFR, or age in these healthy non-diabetic individuals with estimated GFR>60 mL/min/1.73m 2 . Conclusions: Normalizing data relative to creatinine excretion will facilitate including data from males and females in a single analysis. Furthermore, because our ongoing pharmacogenomic study ( NCT02891954 ) is conducted in healthy individuals, this will facilitate detection of genetic associations with limited confounding by other factors such as age and renal function. Registration: NCT02462421 ( clinicaltrials.gov ). Funding: Research grants from the National Institute of Diabetes and Digestive and Kidney Diseases: R21DK105401, R01DK108942, T32DK098107, and P30DK072488.

Patterns of Failure in Triple Negative Breast Cancer Patients in an Urban, Predominately Black Population.

Triple negative breast cancers (TNBC) behave more aggressively than hormone-receptor positive breast cancers. They are also known preferentially to affect young black women, often leading to poorer outcomes compared with those for white women. We sought to evaluate the comprehensive patterns of failure associated with treatment for TNBC at an urban institution with a predominantly black population and to assess the impact of social determinants of health on treatment failure. A retrospective review of TNBC patients treated from 2005 to 2015 was conducted. Detailed patient, tumor, and treatment characteristics and information on patterns of failure were included. With a median follow-up of 46 months, 32 (16%) documented failures occurred. Locoregional failures comprised 84% of failure patterns whether isolated or in combination with distant failure. Treatment failure was associated with insurance type and smoking status, as well as several tumor characteristics. On multivariate analysis, pathologic nodal staging was the most significant predictor of treatment failure. In contrast to previous studies, we found that black women had higher overall survival than white women, but race was not associated with differences in recurrence patterns or with likelihood of treatment failure. Regardless of race, of the patients who recurred, 53% failed in distant and locoregional sites simultaneously, with an additional 34% failing locally only. These results highlight the need for aggressive local therapies in high-risk patients and suggest a need for improved follow-up focusing on detecting locoregional failures. Multidisciplinary care is essential in the management of these patients at time of failure.

Immune checkpoint inhibition in patients treated with stereotactic radiation for brain metastases.

PURPOSE: Stereotactic radiation therapy (SRT) and immune checkpoint inhibitors (ICI) may act synergistically to improve treatment outcomes but may also increase the risk of symptomatic radiation necrosis (RN). The objective of this study was to compare outcomes for patients undergoing SRT with and without concurrent ICI. METHODS AND MATERIALS: Patients treated for BMs with single or multi-fraction SRT were retrospectively reviewed. Concurrent ICI with SRT (SRT-ICI) was defined as administration within 3 months of SRT. Local control (LC), radiation necrosis (RN) risk and distant brain failure (DBF) were estimated by the Kaplan-Meier method and compared between groups using the log-rank test. Wilcoxon rank sum and Chi-square tests were used to compare covariates. Multivariate cox regression analysis (MVA) was performed. RESULTS: One hundred seventy-nine patients treated with SRT for 385 brain lesions were included; 36 patients with 99 lesions received SRT-ICI. Median follow up was 10.3 months (SRT alone) and 7.7 months (SRT- ICI) (p = 0.08). Lesions treated with SRT-ICI were more commonly squamous histology (17% vs 8%) melanoma (20% vs 2%) or renal cell carcinoma (8% vs 6%), (p < 0.001). Non-small cell lung cancer (NSCLC) compromised 60% of patients receiving ICI (n = 59). Lesions treated with SRT-ICI had significantly improved 1-year local control compared to SRT alone (98 and 89.5%, respectively (p = 0.0078). On subset analysis of NSCLC patients alone, ICI was also associated with improved 1 year local control (100% vs. 90.1%) (p = 0.018). On MVA, only tumor size ≤2 cm was significantly associated with LC (HR 0.38, p = 0.02), whereas the HR for concurrent ICI with SRS was 0.26 (p = 0.08). One year DBF (41% vs. 53%; p = 0.21), OS (58% vs. 56%; p = 0.79) and RN incidence (7% vs. 4%; p = 0.25) were similar for SRT alone versus SRT-ICI, for the population as a whole and those patients with NSCLC. CONCLUSION: These results suggest SRT-ICI may improve local control of brain metastases and is not associated with an increased risk of symptomatic radiation necrosis in a cohort of predominantly NSCLC patients. Larger, prospective studies are necessary to validate these findings and better elucidate the impact of SRT-ICI on other disease outcomes.

A multi-center analysis of single-fraction versus hypofractionated stereotactic radiosurgery for the treatment of brain metastasis.

BACKGROUND: Hypofractionated-SRS (HF-SRS) may allow for improved local control and a reduced risk of radiation necrosis compared to single-fraction-SRS (SF-SRS). However, data comparing these two treatment approaches are limited. The purpose of this study was to compare clinical outcomes between SF-SRS versus HF-SRS across our multi-center academic network. METHODS: Patients treated with SF-SRS or HF-SRS for brain metastasis from 2013 to 2018 across 5 radiation oncology centers were retrospectively reviewed. SF-SRS dosing was standardized, whereas HF-SRS dosing regimens were variable. The co-primary endpoints of local control and radiation necrosis were estimated using the Kaplan Meier method. Multivariate analysis using Cox proportional hazards modeling was performed to evaluate the impact of select independent variables on the outcomes of interest. Propensity score adjustments were used to reduce the effects confounding variables. To assess dose response for HF-SRS, Biologic Effective Dose (BED) assuming an α/ß of 10 (BED10) was used as a surrogate for total dose. RESULTS: One-hundred and fifty six patients with 335 brain metastasis treated with SF-SRS (n = 222 lesions) or HF-SRS (n = 113 lesions) were included. Prior whole brain radiation was given in 33% (n = 74) and 34% (n = 38) of lesions treated with SF-SRS and HF-SRS, respectively (p = 0.30). After a median follow up time of 12 months in each cohort, the adjusted 1-year rate of local control and incidence of radiation necrosis was 91% (95% CI 86-96%) and 85% (95% CI 75-95%) (p = 0.26) and 10% (95% CI 5-15%) and 7% (95% CI 0.1-14%) (p = 0.73) for SF-SRS and HF-SRS, respectively. For lesions > 2 cm, the adjusted 1 year local control was 97% (95% CI 84-100%) for SF-SRS and 64% (95% CI 43-85%) for HF-SRS (p = 0.06). On multivariate analysis, SRS fractionation was not associated with local control and only size ≤2 cm was associated with a decreased risk of developing radiation necrosis (HR 0.21; 95% CI 0.07-0.58, p < 0.01). For HF-SRS, 1 year local control was 100% for lesions treated with a BED10 ≥ 50 compared to 77% (95% CI 65-88%) for lesions that received a BED10 < 50 (p = 0.09). CONCLUSIONS: In this comparison study of dose fractionation for the treatment of brain metastases, there was no difference in local control or radiation necrosis between HF-SRS and SF-SRS. For HF-SRS, a BED10 ≥ 50 may improve local control.

Plasma EGF and cognitive decline in Parkinson's disease and Alzheimer's disease.

OBJECTIVE: Cognitive decline occurs in multiple neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). Shared underlying mechanisms may exist and manifest as shared biomarker signatures. Previously, we nominated plasma epidermal growth factor (EGF) as a biomarker predicting cognitive decline in patients with established PD. Here, we investigate EGF as a predictive biomarker in prodromal PD, as well as AD. METHODS: A cohort of PD patients (n = 236) was recruited to replicate our finding that low baseline EGF levels predict future cognitive decline. Additionally, plasma EGF and cognitive outcome measures were obtained from individuals with normal cognition (NC, n = 58), amnestic mild cognitive impairment (AD-MCI, n = 396), and Alzheimer's disease (AD, n = 112) in the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort to investigate whether low EGF levels correlate with cognitive status and outcome in AD-MCI and AD. Third, plasma EGF and cognitive measures were evaluated in the high-risk asymptomatic Parkinson's Associated Risk Study (PARS) cohort (n = 165) to investigate the association of EGF and cognitive performance in a PD prodromal context. RESULTS: In both PD and AD-MCI, low baseline plasma EGF predicted poorer long-term cognitive outcomes. In asymptomatic individuals at highest risk for developing PD from the PARS cohort, low baseline plasma EGF associated with poorer performance in the visuospatial domain but not in other cognitive domains. INTERPRETATION: Low plasma EGF at baseline predicts cognitive decline in both AD and PD. Evidence for this signal may exist in prodromal stages of both diseases.