Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

CTIM-35. A PHASE II STUDY OF GITR AGONIST INCAGN01876 AND PD-1 INHIBITOR RETIFANLIMAB IN COMBINATION WITH STEREOTACTIC RADIOTHERAPY IN PATIENTS WITH RECURRENT GLIOBLASTOMA

BACKGROUND

We evaluated the combination of retifanlimab, INCAGN01876, and FSRT in patients with recurrent GBM.

METHODS

Phase II, single-center, 2 cohort study (A: single-arm non-surgical cohort; B, two-arm neoadjuvant/surgical cohort). Cohort A patients received pre-FSRT one-time doses of retifanlimab (500mg) and INCAGN01876 (300mg), FSRT (8 Gy x 3 fractions), and post-FSRT 28-day treatment cycles (retifanlimab, day 1; INCAGN01876, days 1, 15). Cohort B patients received pre-surgery doses of retifanlimab + INCAGN01876; subsequently, patients either went directly to resection (Sub-Arm 1) or to FSRT followed by resection (Sub-Arm 2). All patients resumed immunotherapy post-operatively. Primary endpoint: ORR in Cohort A. Data cut-off for this analysis was June 30, 2022.

RESULTS

Thirty-two evaluable patients: Cohort A, n=16; Cohort B, n=16 (Sub-Arm 1, n=8, Sub-Arm 2, n=8). Median follow-up time: Cohort A, 13.6 months; Cohort B, 8.8 months. Forty-four percent women, median age 64 (IQR, 55–65), 56% MGMT unmethylated. Most common grade 3/4 treatment-related AEs included cerebral edema (25%), lymphopenia (16%), and cognitive disturbance (13%). Efficacy in Cohort A: no objective responses observed, best response of stable disease achieved in 9/16 patients (56%), median PFS 3.9 months (95% CI 2.1 – 6.2 months), median OS 9.8 months (95% CI 8.3 months – not reached [NR]). Efficacy in Cohort B: median PFS NR, median OS 15.1 months (95% CI 8.5 months – NR). Median PFS and OS are longer in Cohort B Sub-Arm 2 compared to Cohort B Sub-Arm 1 (PFS, NR vs. 2.2 months, p = 0.009; OS, NR vs. 8.5 months, p=0.026). Results of tissue and blood-based immune correlative analyses will be presented.

CONCLUSIONS

The combination of retifanlimab, INCAGN01876, and FSRT is generally well-tolerated in patients with recurrent GBM when administered with or without surgical resection. Survival outcomes in the neoadjuvant cohort are encouraging, largely driven by patients that received neoadjuvant FSRT.

NIMG-67. MULTI-PARAMETRIC MRI-BASED MACHINE LEARNING ANALYSIS FOR PREDICTION OF NEOPLASTIC INFILTRATION AND RECURRENCE IN PATIENTS WITH GLIOBLASTOMA: UPDATES FROM THE MULTI-INSTITUTIONAL RESPOND CONSORTIUM

PURPOSE

Glioblastoma is extremely infiltrative with malignant cells extending beyond the enhancing rim where recurrence inevitably occurs, despite aggressive multimodal therapy. We hypothesize that important characteristics of peritumoral tissue heterogeneity captured and analyzed by multi-parametric MRI and artificial intelligence (AI) methods are generalizable in the updated multi-institutional ReSPOND (Radiomics Signatures for PrecisiON Diagnostics) consortium and predictive of neoplastic infiltration and future recurrence.

METHODS

We used the most recent update of the ReSPOND consortium to evaluate and further refine generalizability of our methods with different scanners and acquisition settings. 179 de novo glioblastoma patients with available T1, T1Gd, T2, T2-FLAIR, and ADC sequences at pre-resection baseline and after complete resection with subsequent pathology-confirmed recurrence were included. To establish generalizability of the predictive models, training and testing of the refined AI model was performed through Leave-One-Institution-Out-Cross-Validation schema. The multi-institutional cohort consisted of the Hospital of the University of Pennsylvania (UPenn, 124), Case Western Reserve University/University Hospitals (CWRU/UH, 27), New York University (NYU, 13), Ohio State University (OSU, 13), and University Hospital Río Hortega (RH, 2). Features extracted from pre-resection MRI were used to build the model predicting the spatial pattern of subsequent tumor recurrence. These predictions were evaluated against regions of pathology-confirmed post-resection recurrence.

RESULTS

Our model predicted the locations that later harbored tumor recurrence with overall odds ratio (99% CI)/AUC (99% CI), 12.0(11.8-12.2)/0.80(0.76-0.85), and per institute, CWRU/UH, 11.0(10.7-11.3)/0.80 (0.64-0.97); NYU, 7.0(6.7-7.3)/0.78(0.56-1.00); OSU, 18.3(17.5-19.1)/0.83(0.54-1.00); RH, 40.0(35.3-45.5)/0.93(0.00-1.00); UPenn, 8.00(7.7-8.3)/0.80(0.75-0.84).

CONCLUSION

This study provides extensive multi-institutional validated evidence that machine learning tools can identify peritumoral neoplastic infiltration and predict location of future recurrence, by decrypting the MRI signal heterogeneity in peritumoral tissue. Our analyses leveraged the unique dataset of the ReSPOND consortium, which aims to develop and validate AI-based biomarkers for individualized prediction and prognostication and establish generalizability in a multi-institutional setting.

NIMG-82. RADIOGENOMIC SIGNATURES OF KEY DRIVER GENES IN GBM REVEAL MOLECULAR HETEROGENEITY OF THE TUMOR MICROENVIRONMENT LINKED TO SPATIAL DISTRIBUTION: IMPACT ON THE TRAJECTORY OF GLIOMA EVOLUTION

Somatic genomic alterations acquired during GBM growth enhance adaptation of tumor cells to their microenvironment and give rise to molecular heterogeneity. Radiogenomics could facilitate exploration of the underlying pathobiology of tumor growth in specific microenvironments and thereby, promote precision medicine for the patients. We derived radiogenomic signatures of key driver genes and evaluated molecular compositions of tumor groups with predisposition to specific brain regions. Pre-operative multiparametric conventional MRI scans of 357 IDH-wildtype GBM patients with available targeted NGS data were jointly segmented and registered into a common template. We constructed spatial distribution atlases for tumors harboring mutations in driver genes and identified four distinct groups of tumor locations with predilection to the left frontal cingulate region (Group1), right temporal (Group2), right parietal (Group3), and occipital pole (Group4). Evaluation of the differences in molecular features of the tumor groups included: (1) exploring similarities of genomic profiles across all four groups by evaluating cosine similarity metric (CSM) between mutational signatures; (2) quantification of molecular heterogeneity based on Mutant Allele Tumor Heterogeneity (MATH) scores; and (3) inference of the evolutionary trajectories. Groups 1 and 4 were the most different, and Groups 2 and 3 were the most similar tumors, molecularly. The mutational signatures between Groups 1 and 4 revealed a CSM of 0.35. Group1 showed significantly lower MATH score (less heterogeneity) compared to Group4 (p&lt; 0.05). Evaluation of evolutionary patterns suggested NF1 mutation as an early event in Group1, without subsequent gain of function or mutation in EGFR. In contrast, in Group4, EGFR mutations were early events triggering PTEN mutations later in the evolutionary trajectory. Radiogenomic signatures revealed distinct molecular underpinnings for the tumors with predilection towards specific brain regions that may suggest existence of different tumor microenvironments in different brain regions that cause intra- and inter-patient heterogeneity in the molecular tumor composition.

NIMG-37. JOINT LEARNING OF IMAGING AND GENOMIC DATA REVEALS DISTINCT GLIOBLASTOMA SUBTYPES

PURPOSE

The significant heterogeneity of glioblastoma is typically displayed on both phenotypical and molecular levels. Non-invasive in vivo approaches to characterize this heterogeneity would potentially facilitate personalized therapies. Here we leverage advanced unsupervised machine learning to integrate radiomic imaging features and genomics to identify distinct subtypes of glioblastoma.

METHODS

A retrospective cohort of 571 IDH-wildtype glioblastoma patients were collected with pre-operative multi-parametric MRI (T1, T1CE, T2, T2-FLAIR, DSC, DTI) scans (available in 462/571 patients) and targeted next-generation sequencing (NGS) data (available in 355/571 patients). Radiomic features (n= 971) were extracted from these MRI scans and a subset of 12 features were selected by L21-norm minimization. A total of 14 key driver genes in the 5 main pathways that are most frequently altered in glioblastoma were chosen. Subtypes were identified by a joint learning approach called Anchor-based Partial Multi-modal Clustering (APMC) on both radiomic and genomic modalities.

RESULTS

Three distinct glioblastoma subtypes were discovered by APMC based on 14-dimension NGS data together with 12 selected radiomic features representing characteristics from histograms, shape, and volumetric measures for different tumor sub-regions. The identified subtypes were 1) high-risk; 2) medium-risk; and 3) low-risk, in terms of their overall survival outcome in Kaplan-Meier analysis (p= 5.52e-6, log-rank test; HR= 1.51, 95%CI:1.20-1.74, Cox proportional hazard model). The three subtypes also displayed different molecular characteristics: subtype 1 exhibited increased frequency of mutation in [EGFR, PIK3CA, PTEN, NF1], subtype 3 showed frequently mutated [PDGFRA, ATRX], while subtype 2 did not show significant differences for mutations in any of these genes.

CONCLUSION

Our results revealed the synergistic value of integrated radiomic signatures and molecular characteristics for glioblastoma subtyping. Joint learning on both modalities could help better understand the molecular basis of phenotypical signatures of glioblastoma and further provide insights into the biologic underpinnings of tumor formation and progression.

CTIM-18. PHASE 2 STUDY OF PD-1 BLOCKADE WITH PEMBROLIZUMAB PLUS RE-IRRADIATION FOR RECURRENT GLIOBLASTOMA (RGBM) (NCT03661723)

Re-irradiation is therapeutically considered for select rGBM patients and may induce immunogenic cell death to stimulate anti-tumor immune responses. Our phase 2 study of re-irradiation with pembrolizumab among rGBM patients evaluated the efficacy and safety of this regimen.

METHODS

Adult rGBM patients with KPS ≥ 70, a maximum supratentorial tumor diameter of 6 cm who were on ≤ 2mg dexamethasone/day and were ≥ 6 months from initial conventional radiation therapy were eligible. Cohort A (bevacizumab [BEV]-naïve) had ≤ 2 prior progressions while cohort B (BEV-refractory) allowed unlimited progressions but only one on prior BEV. Re-irradiation included 35 Gy over 10 fractions to residual enhancing (cohort A) as well as enhancing + non-enhancing (cohort B) disease. Pembrolizumab was administered at 200 mg every three weeks beginning within one week of re-irradiation start. BEV was administered at 15 mg/kg every three weeks for cohort B only.

RESULTS

Sixty patients enrolled (n = 30 per cohort) with a median age of 61 years (range 20-76), 47% were female and 53% enrolled after 2 or more progressions. Grade 3 events deemed at least possibly related to study therapy in &gt; one patient for cohort A included headache (n = 2) and for cohort B included elevated ALT (n = 2) and hypertension (n = 5). No grade 4 events occurred in more than single patients per cohort and no grade 5 events occurred. Median PFS and PFS-6 were 4.9 months (95% CI: 3.5, 5.6) and 26.0% (95% CI: 12.3%, 43.0%) for cohort A and 4.14 months (95% CI: 3.45, 5.42) and 16.9% (95% CI: 5.4, 33.7) for cohort B. Median survival for cohorts A and B were 11.5 months (95% CI: 9.6, 14.1) and 7.6 months (95% CI 5.5, 9.3), respectively.

CONCLUSIONS

Re-irradiation with pembrolizumab was overall well tolerated and achieved comparable efficacy to historical salvage therapy established with lomustine.

NIMG-33. PROGNOSTIC STRATIFICATION OF DE NOVO GLIOBLASTOMA PATIENTS ACROSS 22 GEOGRAPHICALLY DISTINCT INSTITUTIONS: UPDATES FROM THE RESPOND CONSORTIUM

PURPOSE

Glioblastoma, IDH-wildtype, is the most common primary malignant adult brain tumor with median overall survival (OS) of ~14 months, with little improvement over the last 20 years. We hypothesize that AI-based integration of quantitative tumor characteristics, independent of acquisition protocol and equipment, can reveal accurate generalizable prognostic stratification. We seek an AI-based OS predictor using routine clinically acquired MRI sequences, quantitatively evaluated across institutions of the ReSPOND (Radiomics Signatures for PrecisiON Diagnostics) consortium.

METHODS

We identified a retrospective cohort of 2,293 diffuse glioma (IDH-wildtype/-NOS/-NEC) patients from 22 geographically distinct institutions across 3 continents, with preoperative structural MRI scans. The entire tumor burden was automatically segmented into 3 sub-compartments, i.e., enhancing, necrotic, peritumoral T2-FLAIR abnormality. We developed our AI predictor by multivariate integration of i)patient age, ii)tumor sub-compartment volume normalized to brain volume, iii)spatial distribution characteristics (tumor location, distance to the ventricles, and laterality), and iv)morphologic descriptors (major axes’ length, axes’ ratio, extent, and number of tumors). The AI predictor returns a continuous value between 0-1, defining short-, intermediate-, and long-survivors based on thresholds on the 25th and 75th percentiles. Leave-One-Site-Out-Cross-Validation was used to assess the generalizability of our stratification. Kaplan-Meier survival curves were computed for OS analysis and evaluated by a Cox proportional hazards model for statistical significance and hazard ratios.

RESULTS

Survival analysis yielded a hazard ratio of 2.07 (95%CI, 2.06-2.08, p-value= 4.8e-102) for patient stratification into short-, intermediate-, and long-survivors. Pearson correlation between the predicted and actual OS yielded an R= 0.49.

CONCLUSION

Multivariate integration of visually quantified tumor characteristics, agnostic to acquisition protocol/equipment, yields an accurate OS surrogate index. Validation of our AI model in the largest centralized glioblastoma imaging dataset, from the ReSPOND consortium, supports its generalizability across diverse patient populations and acquisition settings, potentially contributing to equitable improvements of personalized patient care.

A Probability-Based Investigation on the Setup Robustness of Pencil-beam Proton Radiation Therapy for Skull-Base Meningioma

Introduction

The intracranial skull-base meningioma is in proximity to multiple critical organs and heterogeneous tissues. Steep dose gradients often result from avoiding critical organs in proton treatment plans. Dose uncertainties arising from setup errors under image-guided radiation therapy are worthy of evaluation.

Patients and Methods

Fourteen patients with skull-base meningioma were retrospectively identified and planned with proton pencil beam scanning (PBS) single-field uniform dose (SFUD) and multifield optimization (MFO) techniques. The setup uncertainties were assigned a probability model on the basis of prior published data. The impact on the dose distribution from nominal 1-mm and large, less probable setup errors, as well as the cumulative effect, was analyzed. The robustness of SFUD and MFO planning techniques in these scenarios was discussed.

Results

The target coverage was reduced and the plan dose hot spot increased by all setup uncertainty scenarios regardless of the planning techniques. For 1 mm nominal shifts, the deviations in clinical target volume (CTV) coverage D99% was -11 ± 52 cGy and -45 ± 147 cGy for SFUD and MFO plans. The setup uncertainties affected the organ at risk (OAR) dose both positively and negatively. The statistical average of the setup uncertainties had <100 cGy impact on the plan qualities for all patients. The cumulative deviations in CTV D95% were 1 ± 34 cGy and -7 ± 18 cGy for SFUD and MFO plans.

Conclusion

It is important to understand the impact of setup uncertainties on skull-base meningioma, as the tumor target has complex shape and is in proximity to multiple critical organs. Our work evaluated the setup uncertainty based on its probability distribution and evaluated the dosimetric consequences. In general, the SFUD plans demonstrated more robustness than the MFO plans in target coverages and brainstem dose. The probability-weighted overall effect on the dose distribution is small compared to the dosimetric shift during single fraction.

Histopathology-validated machine learning radiographic biomarker for noninvasive discrimination between true progression and pseudo-progression in glioblastoma

BACKGROUND

Imaging of glioblastoma patients after maximal safe resection and chemoradiation commonly demonstrates new enhancements that raise concerns about tumor progression. However, in 30% to 50% of patients, these enhancements primarily represent the effects of treatment, or pseudo-progression (PsP). We hypothesize that quantitative machine learning analysis of clinically acquired multiparametric magnetic resonance imaging (mpMRI) can identify subvisual imaging characteristics to provide robust, noninvasive imaging signatures that can distinguish true progression (TP) from PsP.

METHODS

We evaluated independent discovery (n = 40) and replication (n = 23) cohorts of glioblastoma patients who underwent second resection due to progressive radiographic changes suspicious for recurrence. Deep learning and conventional feature extraction methods were used to extract quantitative characteristics from the mpMRI scans. Multivariate analysis of these features revealed radiophenotypic signatures distinguishing among TP, PsP, and mixed response that compared with similar categories blindly defined by board-certified neuropathologists. Additionally, interinstitutional validation was performed on 20 new patients.

RESULTS

Patients who demonstrate TP on neuropathology are significantly different (P < .0001) from those with PsP, showing imaging features reflecting higher angiogenesis, higher cellularity, and lower water concentration. The accuracy of the proposed signature in leave-one-out cross-validation was 87% for predicting PsP (area under the curve [AUC], 0.92) and 84% for predicting TP (AUC, 0.83), whereas in the discovery/replication cohort, the accuracy was 87% for predicting PsP (AUC, 0.84) and 78% for TP (AUC, 0.80). The accuracy in the interinstitutional cohort was 75% (AUC, 0.80).

CONCLUSION

Quantitative mpMRI analysis via machine learning reveals distinctive noninvasive signatures of TP versus PsP after treatment of glioblastoma. Integration of the proposed method into clinical studies can be performed using the freely available Cancer Imaging Phenomics Toolkit.

Risk of brainstem necrosis in pediatric patients with central nervous system malignancies after pencil beam scanning proton therapy

Background: Radiation therapy (RT) plays an important role in management of pediatric central nervous system (CNS) malignancies. Centers are increasingly utilizing pencil beam scanning proton therapy (PBS-PT). However, the risk of brainstem necrosis has not yet been reported. In this study, we evaluate the rate of brainstem necrosis in pediatric patients with CNS malignancies treated with PBS-PT.Material and methods: Pediatric patients with non-hematologic CNS malignancies treated with PBS-PT who received dose to the brainstem were included. All procedures were approved by the institutional review board. Brainstem necrosis was defined as symptomatic toxicity. The actuarial rate was analyzed by the Kaplan Meier method.Results: One hundred and sixty-six consecutive patients were reviewed. Median age was 10 years (range 0.5-21 years). Four patients (2.4%) had prior radiation. Median maximum brainstem dose in the treated course was 55.4 Gy[RBE] (range 0.15-61.4 Gy[RBE]). In patients with prior RT, cumulative median maximum brainstem dose was 98.0 Gy [RBE] (range 17.0-111.0 Gy [RBE]). Median follow up was 19.6 months (range, 2.0-63.0). One patient who had previously been treated with twice-daily radiation therapy and intrathecal (IT) methotrexate experienced brainstem necrosis. The actuarial incidence of brainstem necrosis was 0.7% at 24 months (95% CI 0.1-5.1%).Conclusion: The rate of symptomatic brainstem necrosis was extremely low after treatment with PBS-PT in this study. Further work to clarify clinical and dosimetric parameters associated with risk of brainstem necrosis after PBS-PT is needed.

TMOD-34. A RADIOMIC SIGNATURE OF INFILTRATION IN PERITUMORAL EDEMA PREDICTS SUBSEQUENT RECURRENCE IN GLIOBLASTOMA

BACKGROUND

The malignant parenchyma in glioblastoma extends beyond the enhancing borders of tumor on postcontrast T1-weighted magnetic resonance imaging (MRI), which is the primary target of treatment. Such non-enhancing tumor invasion into the peri-tumoral edema (PED) is, however, not usually distinguishable on conventional MRI. The aim of this study was to evaluate pre-operative MRI in the PED to assess whether areas of tumor infiltration and early recurrence can be detected.

METHODS

A cohort of 90 de novo glioblastoma patients from a single institution (Penn) was selected. All included patients had preoperative multi-parametric MRI (mpMRI;T1,T1Gd,T2,T2-FLAIR,ADC), underwent initial gross-total-resection followed by standard chemoradiation, and had pathologically-confirmed recurrence. An extensive panel of handcrafted features, including shape, volume, intensity distributions, texture, was extracted from mpMRI scans. Predictive modeling for estimation of PED infiltration was performed using sequential feature selection approach designed with a support vector machine classifier and through a Leave-one-out cross-validation approach in the Penn cohort. Generalizability of the model was evaluated by applying it on a cohort of 20 patients from a second institution (Case), and predicted probability distributions in PED were compared in both the cohorts.

RESULTS

Spatial probability maps, representing the likelihood of tumor infiltration and eventual recurrence, were binarized at 50% cutoff, and compared with actual recurrence on post-recurrence scans. The cross-validated accuracy of our model within Penn cohort was 81.35% (odds-ratio=3.62, sensitivity/specificity=78.26/81.35). The model trained on the Penn cohort, when applied on the Case cohort, produced almost similar intensity distribution in the PED, suggesting that the method has potential for robust performance across institutions. The comparison of intensity distributions revealed higher ADC and T2-FLAIR in non-recurrent regions compared to recurrent ones.

CONCLUSION

Multi-parametric pattern analysis of mpMRI across multiple institutions generates similar, accurate estimates of spatial extent and patterns of recurrence in PED, which may guide strategies for treatment intensification in glioblastoma.

Evaluating the Impact of Secure Mobile Messaging on Communication and Cancer Care Team Satisfaction in a Large Radiation Oncology Clinic

PURPOSE

Communication is crucial in any clinical environment for efficient delivery of care and ensuring patient safety. A 2016 National Database of Nursing Quality Indicators questionnaire indicated poor physician-nurse satisfaction with communication in our department. We addressed gaps in our communication procedures by implementing a communication policy with a secure mobile messaging platform, and we surveyed care team members to evaluate the effectiveness of the implementation.

METHODS

We designed a policy around best communication practices and implemented a secure mobile messaging platform, Cureatr, which enables closed-loop, two-way communication that is compliant with the Health Insurance Portability and Accountability Act. Pre- and postimplementation surveys evaluated self-reported impression of efficiency, timeliness, effectiveness, and overall quality of communication, which were scored on a 5-point Likert scale. The number of messages sent was evaluated as a measure of uptake in use, and patient navigation data were queried to measure changes in clinic workflow.

RESULTS

After implementation of Cureatr and a communication policy, survey responses demonstrated a clear improvement in staff satisfaction with the efficiency, timeliness, effectiveness, and overall quality of communication. The number of messages sent reflected a progressive increase in use of Cureatr; however, a consistent improvement in clinical workflow as measured by a decrease in patient in-room time was not appreciated.

CONCLUSION

Implementing a secure messaging application with a communication policy improved cancer care team satisfaction with communication on all levels. Additional work is needed to evaluate the impact of secure messaging on clinical workflows, patient satisfaction, and staff well-being.

An Interactive Virtual Reality Tour for Adolescents Receiving Proton Radiation Therapy: Proof-of-Concept Study

BACKGROUND

Child life therapists provide patient education for children undergoing radiation therapy to assist in coping with and understanding their treatment.

OBJECTIVE

This proof-of-concept study aimed to determine the feasibility of incorporating a 360-degree video tour via a virtual reality system for children scheduled to receive radiation therapy. The secondary objective was to qualitatively describe each subject's virtual reality experience.

METHODS

Children aged ≥13 years scheduled to receive proton radiation therapy were included in the study. Subjects watched the 360-degree video of the radiation therapy facility in an immersive virtual reality environment with a child life therapist experienced in coaching children receiving radiation therapy and completed a survey after the tour.

RESULTS

Eight subjects consented to participate in the study, and six subjects completed the 360-degree video tour and survey. All the enrolled patients completed the tour successfully. Two subjects did not complete the survey. Two subjects requested to pause the tour to ask questions about the facility. Five subjects said the tour was helpful preparation before undergoing proton radiation therapy. Subjects stated that the tour was helpful because "it showed [them] what's to come" and was helpful to see "what it's like to lay in the machine." One subject said, "it made me feel less nervous." Six subjects stated that they would like to see this type of tour available for other areas of the hospital, such as diagnostic imaging rooms. None of the subjects experienced nausea or vomiting.

CONCLUSIONS

The 360-degree video tour allowed patients to explore the treatment facility in a comfortable environment. Participants felt that the tour was beneficial and would appreciate seeing other parts of the hospital in this manner.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Radiomic signature of infiltration in peritumoral edema predicts subsequent recurrence in glioblastoma: implications for personalized radiotherapy planning

Standard surgical resection of glioblastoma, mainly guided by the enhancement on postcontrast T1-weighted magnetic resonance imaging (MRI), disregards infiltrating tumor within the peritumoral edema region (ED). Subsequent radiotherapy typically delivers uniform radiation to peritumoral FLAIR-hyperintense regions, without attempting to target areas likely to be infiltrated more heavily. Noninvasive in vivo delineation of the areas of tumor infiltration and prediction of early recurrence in peritumoral ED could assist in targeted intensification of local therapies, thereby potentially delaying recurrence and prolonging survival. This paper presents a method for estimating peritumoral edema infiltration using radiomic signatures determined via machine learning methods, and tests it on 90 patients with de novo glioblastoma. The generalizability of the proposed predictive model was evaluated via cross-validation in a discovery cohort ([Formula: see text]) and was subsequently evaluated in a replication cohort ([Formula: see text]). Spatial maps representing the likelihood of tumor infiltration and future early recurrence were compared with regions of recurrence on postresection follow-up studies with pathology confirmation. The cross-validated accuracy of our predictive infiltration model on the discovery and replication cohorts was 87.51% (odds ratio = 10.22, sensitivity = 80.65, and specificity = 87.63) and 89.54% (odds ratio = 13.66, sensitivity = 97.06, and specificity = 76.73), respectively. The radiomic signature of the recurrent tumor region revealed higher vascularity and cellularity when compared with the nonrecurrent region. The proposed model shows evidence that multiparametric pattern analysis from clinical MRI sequences can assist in in vivo estimation of the spatial extent and pattern of tumor recurrence in peritumoral edema, which may guide supratotal resection and/or intensification of postoperative radiation therapy.

Proton therapy for pediatric head and neck malignancies

PURPOSE

Pediatric head and neck malignancies are managed with intensive multimodality therapy. Proton beam therapy (PBT) may reduce toxicity by limiting exposure of normal tissue to radiation. In this study, we report acute toxicities and early outcomes following PBT for pediatric head and neck malignancies.

MATERIALS AND METHODS

Between 2010 and 2016, pediatric patients with nonhematologic malignancies of the head and neck were treated with PBT. Clinical and dosimetric data were abstracted from the medical record and treatment planning system with institutional review board approval.

RESULTS

Sixty-nine consecutive pediatric patients were treated with proton-based radiotherapy for head and neck malignancies. Thirty-five were treated for rhabdomyosarcoma to a median dose of 50.4 Gy relative biological effectiveness [RBE]. Ten patients were treated for Ewing sarcoma to a median dose of 55.8 Gy[RBE]. Twenty-four patients were treated for other histologies to a median dose of 63.0 Gy[RBE]. Grade 3 oral mucositis, anorexia, and dysphagia were reported to be 4, 22, and 7%, respectively. Actuarial 1-year freedom from local recurrence was 92% (95% CI 80-97). Actuarial 1-year overall survival was 93% (95% CI 79-98) in the entire cohort. Oral cavity mucositis was significantly correlated with oral cavity dose (D80 and D50 [P < 0.05], where D80 and D50 are dose to 50% of the volume and dose to 80% of the volume, respectively).

CONCLUSIONS

In this study, we report low rates of acute toxicity in a cohort of pediatric patients with head and neck malignancies. PBT appears safe for this patient population, with local control rates similar to historical reports. Longer follow-up will be required to evaluate late toxicity and long-term disease control.

Intracranial control after Cyberknife radiosurgery to the resection bed for large brain metastases

Background

Stereotactic radiosurgery (SRS) is an alternative to post-operative whole brain radiation therapy (WBRT) following resection of brain metastases. At our institution, CyberKnife (CK) is considered for local treatment of large cavities ≥2 cm. In this study, we aimed to evaluate patterns of failure and characterize patients best suited to treatment with this approach.

Methods

We retrospectively reviewed 30 patients treated with CK to 33 resection cavities ≥2 cm between 2011 and 2014. Patterns of intracranial failure were analyzed in 26 patients with post-treatment imaging. Survival was estimated by the Kaplan-Meier method and prognostic factors examined with log-rank test and Cox proportional hazards model.

Results

The most frequent histologies were lung (43 %) and breast (20 %). Median treatment volume was 25.1 cm³ (range 4.7–90.9 cm³) and median maximal postoperative cavity diameter was 3.8 cm (range 2.8–6.7). The most common treatment was 30 Gy in 5 fractions prescribed to the 75 % isodose line. Median follow up for the entire cohort was 9.5 months (range 1.0–34.3). Local failure developed in 7 treated cavities (24 %). Neither cavity volume nor CK treatment volume was associated with local failure. Distant brain failure occurred in 20 cases (62 %) at a median of 4.2 months. There were increased rates of distant failure in patients who initially presented with synchronous metastases (p = 0.02). Leptomeningeal carcinomatosis (LMC) developed in 9 cases, (34 %). Salvage WBRT was performed in 5 cases (17 %) at a median of 5.2 months from CK. Median overall survival was 10.1 months from treatment.

Conclusions

This study suggests that adjuvant CK is a reasonable strategy to achieve local control in large resection cavities. Patients with synchronous metastases at the time of CK may be at higher risk for distant brain failure. The majority of cases were spared or delayed WBRT with the use of local CK therapy.

Development and clinical implementation of a universal bolus to maintain spot size during delivery of base of skull pencil beam scanning proton therapy

PURPOSE

To report on a universal bolus (UB) designed to replace the range shifter (RS); the UB allows the treatment of shallow tumors while keeping the pencil beam scanning (PBS) spot size small.

METHODS AND MATERIALS

Ten patients with brain cancers treated from 2010 to 2011 were planned using the PBS technique with bolus and the RS. In-air spot sizes of the pencil beam were measured and compared for 4 conditions (open field, with RS, and with UB at 2- and 8-cm air gap) in isocentric geometry. The UB was applied in our clinic to treat brain tumors, and the plans with UB were compared with the plans with RS.

RESULTS

A UB of 5.5 cm water equivalent thickness was found to meet the needs of the majority of patients. By using the UB, the PBS spot sizes are similar with the open beam (P>.1). The heterogeneity index was found to be approximately 10% lower for the UB plans than for the RS plans. The coverage for plans with UB is more conformal than for plans with RS; the largest increase in sparing is usually for peripheral organs at risk.

CONCLUSIONS

The integrity of the physical properties of the PBS beam can be maintained using a UB that allows for highly conformal PBS treatment design, even in a simple geometry of the fixed beam line when noncoplanar beams are used.

Gamma Knife radiosurgery to four or more brain metastases in patients without prior intracranial radiation or surgery

Data on stereotactic radiosurgery (SRS) for four or more metastases are limited. Existing studies are confounded by significant proportions of patients receiving prior whole-brain radiation therapy (WBRT) or concurrent WBRT with SRS. Furthermore, published results disagree about the impact of tumor volume on overall survival. A retrospective review identified 38 patients without prior intracranial radiation or surgery who received Gamma Knife (GK) as sole treatment to ≥4 brain metastases in a single session. Twenty-eight cases with follow-up imaging were analyzed for intracranial progression. Prognostic factors were examined by univariate (log-rank test) and multivariate (Cox proportional hazards model) analyses. Common primary tumors were non-small cell lung (45%), melanoma (37%), and breast (8%). Cases were recursive partitioning analysis class II (94%) or III (6%). Patients harbored a median five tumors (range 4–12) with median total tumor volume of 1.2 cc. A median dose of 21 Gy was prescribed to the 50% isodose line. Patients survived a median 6.7 months from GK. Local treatment failure occurred in one case (4%) and distant failure in 22 (79%). On multivariate analysis, total tumor volume ≥3 cc was significantly associated with distant failure and worsened overall survival (P = 0.042 and 0.040). Fourteen patients (37%) underwent salvage WBRT at a median 10.3 months from GK and seven patients received repeat GK. GK as sole initial treatment for four or more simultaneous metastases spares some patients WBRT and delays it for others. Increased total tumor volume (≥3 cc) is significantly associated with worsened overall survival.

Proton versus photon radiation therapy for patients with high-risk neuroblastoma: the need for a customized approach

BACKGROUND

Proton therapy for treatment for high-risk neuroblastoma may offer sparing of organs at risk (OAR) when compared to intensity-modulated X-ray therapy (IMXT).

PROCEDURE

Double-scattered proton plans and IMXT plans delivering 2,160 cGy to the primary tumor site and other residual disease were developed for 13 consecutive HR-NBL patients. Radiation doses to target volumes and OAR were calculated to determine the optimal modality for each.

RESULTS

All patients received radiation (5/13 ≥ 2 sites). No patient has experienced local recurrence or clinical organ toxicity. Coverage was excellent using both protons and IMXT: median % dose delivered to 95% clinical target volume was 99% and 100%, respectively. For nine patients with lateralized disease, proton therapy offered sparing of the contralateral kidney both with regard to median dose and dose to 20% (median <1 cGy vs. 362 cGy, P = 0.01; median 100 cGy vs. 634 cGy, P = 0.02, respectively). Proton therapy did not reduce ipsilateral kidney dose, and for 2 select patients with lateralized disease IMXT improved overall bilateral renal sparing. Proton therapy improved median bowel (median 33 cGy vs. 590 cGy, P = 0.01), total body (median <1 cGy vs. 30 cGy, P = 0.15), and liver dose (median <1 cGy vs. 529, P < 0.001). When chest RT was required, proton therapy decreased median heart dose and mean lung dose.

CONCLUSIONS

For most patients (11/13), proton therapy offered the optimal combination of target coverage and organ sparing, and is a feasible treatment for HR-NBL. We recommend a customized approach with careful evaluation of renal dosimetry; IMXT may be preferred for select patients.

Compliance with therapeutic guidelines in Radiation Therapy Oncology Group prospective gastrointestinal clinical trials

BACKGROUND

This report analyzes the adherence to radiation therapy protocol guidelines in contemporary Radiation Therapy Oncology Group (RTOG) gastrointestinal trials. We aim to provide insight into current standards and compliance of radiation therapy field design and administration.

METHODS

From 1994 to 2006, the Gastrointestinal Cancer Committee of the RTOG initiated and completed 15 phase I-III clinical trials utilizing radiation therapy in the multimodality treatment of gastrointestinal cancers. In each protocol, details for planning and executing radiation therapy were outlined and each protocol contained scoring criteria for these components of radiation therapy, characterized according to per-protocol, variation acceptable and deviation unacceptable. Review of treatment planning and implementation was performed in all studies following therapy completion.

RESULTS

Radiation therapy planning and implementation was reviewed in 2309 of 2312 (99.9%) patients. The mean rate of compliance over all for the 15 protocols was 65% (total of the 2309 analyzed patients). The mean variation acceptable rate was 21% whereas the mean deviation unacceptable rate was 5%. The mean "other" rate (no RT given or incomplete RT due to death, progression or refusal) was 8%. Two of the 15 trials (13%) had deviation unacceptable rates >10%. In four studies incorporating pre-treatment review of radiation therapy planning and treatment, compliance with protocol therapy was enhanced.

CONCLUSIONS

The fidelity of radiation planning and execution detailed in protocol to actual therapy is heterogeneous, with a mean per-protocol rate of 65%. As clinical trials evolve, available technology should permit efficient pre-treatment review processes, thus facilitating compliance to protocol therapy. These analyses should also permit prospective analysis of outcome measures by compliance to therapy.

Cranial irradiation increases risk of stroke in pediatric brain tumor survivors

BACKGROUND AND PURPOSE

The purposes of this study were to determine the incidence of neurovascular events as late complications in pediatric patients with brain tumor and to evaluate radiation as a risk factor.

METHODS

Patients were ascertained using the tumor database of a pediatric tertiary care center. Included patients had a primary brain tumor, age birth to 21 years, initial treatment January 1, 1993, to December 31, 2002, and at least 2 visits with neuro-oncology. Radiation exposure included: whole brain, whole brain plus a focal boost, or focal brain. The primary outcome was stroke or transient ischemic attack.

RESULTS

Of 431 subjects, 14 had 19 events of stroke or transient ischemic attack over a median follow-up of 6.3 years. The incidence rate was 548/100 000 person-years. Overall, 61.5% of subjects received radiation, including 13 of 14 subjects with events. Median time from first radiation to first event was 4.9 years. The stroke/transient ischemic attack hazard ratio for any brain irradiation was 8.0 (95% CI, 1.05-62; P=0.045); for the circle of Willis, radiation was 9.0 (95% CI, 1.2-70; P=0.035); and for focal noncircle of Willis, radiation was 3.4 (95% CI, 0.21-55; P=0.38).

CONCLUSIONS

The incidence of neurovascular events in this population is 100-fold higher than in the general pediatric population and cranial irradiation is an important risk factor. By defining the incidence of this late effect, physicians are better able to counsel parents regarding treatment, monitor patients at risk, and target a population for primary stroke prevention in future studies.

Long-term follow-up of the RTOG 9501/intergroup phase III trial: postoperative concurrent radiation therapy and chemotherapy in high-risk squamous cell carcinoma of the head and neck

PURPOSE

Previous analysis of this Intergroup trial demonstrated that with a median follow-up among surviving patients of 45.9 months, the concurrent postoperative administration of cisplatin and radiation therapy improved local-regional control and disease-free survival of patients who had high-risk resectable head-and-neck carcinomas. With a minimum of 10 years of follow-up potentially now available for all patients, these results are updated here to examine long-term outcomes.

METHODS AND MATERIALS

A total of 410 analyzable patients who had high-risk resected head-and-neck cancers were prospectively randomized to receive either radiation therapy (RT: 60 Gy in 6 weeks) or identical RT plus cisplatin, 100 mg/m(2)i.v. on days 1, 22, and 43 (RT + CT).

RESULTS

At 10 years, the local-regional failure rates were 28.8% vs 22.3% (P=.10), disease-free survival was 19.1% vs 20.1% (P=.25), and overall survival was 27.0% vs 29.1% (P=.31) for patients treated by RT vs RT + CT, respectively. In the unplanned subset analysis limited to patients who had microscopically involved resection margins and/or extracapsular spread of disease, local-regional failure occurred in 33.1% vs 21.0% (P=.02), disease-free survival was 12.3% vs 18.4% (P=.05), and overall survival was 19.6% vs 27.1% (P=.07), respectively.

CONCLUSION

At a median follow-up of 9.4 years for surviving patients, no significant differences in outcome were observed in the analysis of all randomized eligible patients. However, analysis of the subgroup of patients who had either microscopically involved resection margins and/or extracapsular spread of disease showed improved local-regional control and disease-free survival with concurrent administration of chemotherapy. The remaining subgroup of patients who were enrolled only because they had tumor in 2 or more lymph nodes did not benefit from the addition of CT to RT.

Risk factors for obesity and high blood pressure in Chinese American children: maternal acculturation and children's food choices

The objective of this study is to explore risk factors associated with overweight and high blood pressure in Chinese American children. Students and their parents were recruited from Chinese language schools in the San Francisco Bay Area. Data were collected on 67 children and their mothers, and included children’s weight, height, waist and hip circumferences, blood pressure, level of physical activity, dietary intake, usual food choice, knowledge about nutrition and physical activity, and self-efficacy regarding diet and physical activity. Mothers completed questionnaires on demographic data and acculturation. About 46% of children had a body mass index exceeding the 85th percentile. Lower level of maternal acculturation is a risk factor for overweight and higher waist to hip ratio. Children’s unhealthy food choices were predictive of high body mass index and high systolic blood pressure, whereas older age and less physical activity in children were predictors of high diastolic blood pressure. Developing culturally sensitive and developmentally appropriate interventions to reduce overweight and high blood pressure is critical to reduce health disparities among minority children.