Phase II randomized study comparing proton craniospinal irradiation with photon involved-field radiotherapy for patients with solid tumor leptomeningeal metastasis

2000

Background: Leptomeningeal metastasis (LM) is associated with limited survival and treatments. Photon involved-field radiotherapy (IFRT) is the standard of care radiotherapy (RT) but benefits are limited. We hypothesized that proton craniospinal irradiation (pCSI) encompassing the central nervous system (CNS) compartment would result in superior CNS disease control compared to IFRT. Methods: We conducted a randomized phase 2 study comparing pCSI vs. IFRT in patients with non-small cell lung cancer (NSCLC) or breast cancer LM. Eligibility criteria included radiographic and/or cytologic LM and Karnofsky performance status (KPS) ≥ 60. Patients were stratified by histology (breast vs. NSCLC) and systemic disease (active vs. stable) and were randomized in a 2:1 ratio of pCSI:IFRT. Patients with all other solid tumor histologies were enrolled to an exploratory pCSI arm. RT was 3Gy x 10 fractions for all patients. The primary endpoint is CNS progression-free survival (CNS PFS), defined as time from randomization to CNS progression (POD); secondary endpoints include overall survival (OS) and treatment-related adverse events (TAEs). A target of 81 patients to compare pCSI and IFRT was designed with a one-sided alpha of 0.025 and a power of 0.8 based on stratified log-rank test. Analysis is based on intent-to-treat. Results: From 4/2020-10/2021, 42 and 21 patients were randomized to pCSI and IFRT, respectively. Baseline factors were not different: median age was 56 vs. 61 years (p = 0.5); both cohorts included 57% NSCLC and 52% with active systemic disease. At median follow up of 7.1 months, 25 patients had CNS POD (pCSI = 9 [21%], IFRT = 16 [76%]) and 28 died (pCSI = 15 [36%], IFRT = 13 [62%]). At planned interim analysis, significant benefit in CNS PFS was observed with pCSI (median = 7.5 months, 95% CI: 6.6-NA) vs. IFRT (median = 2.0, 95% CI: 1.0-5.1, p < 0.001). As a result, the Data and Safety Monitoring Committee recommended early discontinuation of the trial. In addition, OS benefit with pCSI (median = 8.2 months, 95% CI: 7.4-NA) vs. IFRT (median = 4.9 months, 95% CI: 3.1-NA, p = 0.04) was observed. In a multivariable analysis including age, KPS and stratification factors, CNS PFS and OS benefit for pCSI remained significant. Grade 3 non-heme TAEs occurred in 3 patients with pCSI and 5 with IFRT. For the exploratory pCSI cohort, 35 patients enrolled, the median age was 61, 20 (57%) had active systemic disease and ovarian (7 [20%]) was the most common histology. At median follow up of 9.6 months, 7 (20%) had CNS POD and 20 (57%) died. Median CNS PFS was 5.4 months (95% CI: 4.8-9.1), OS was 6.6 months (95% CI: 5.4-12.1) and 4 patients had Grade 3 TAEs. Conclusions: In this trial, the first randomized study of RT for LM, we demonstrated improved CNS PFS of pCSI compared to IFRT, meeting the primary endpoint. pCSI also had a significant OS benefit. Grade 3 toxicities were comparable. Clinical trial information: NCT04343573.

Genomic analysis and clinical correlations of non-small cell lung cancer (NSCLC) brain metastasis (BM)

2008

Background: Approximately 30% of patients with NSCLC present with BM, and up to 50% of patients ultimately develop BM. While modern NSCLC-directed agents yield excellent systemic response, most patients require focal treatment. Prior reports of BM genomics have been limited by low numbers, missing clinical data, and lack of matched specimens. Here, we report the largest cohort to date of molecularly profiled NSCLC BM samples with clinical correlates. Methods: Clinical data and outcomes for 244 patients with NSCLC and resected BM were identified, and BM samples were assessed with one of four versions (341, 410, 468, 505) of MSK-IMPACT, a custom FDA-approved next generation sequencing-based tumor sequencing assay. 51 (20.9%) patients had matched primary site tissue, and 44 (18%) patients had matched tissue from another metastatic site or CSF. Genomic alterations were filtered for driver variants using OncoKB. Results: Median age was 66 years (range 31-91), and median follow-up was 2.3 years (IQR 1.3-4.3). Adenocarcinoma was the most common histology (183, 78%). Half presented with a single BM, and 121 (51%) patients were treatment naive. Most (197, 83%) received adjuvant stereotactic radiosurgery (SRS) to the resection site and 28% received SRS to additional BM. After resection, 130 (55.1%) had CNS progression, often regional (54, 42%). SRS to new BMs (32%) was the most common salvage treatment. Median overall survival from BM diagnosis was 2.5 years (95%CI 2.1-3.2). Median CNS-progression-free survival was 1.2 years (95%CI 0.9-1.4). The most frequently altered genes in BM samples were TP53 (72%), CDKN2A (34%), KRAS (31%), KEAP1 (26%), and EGFR (21%). CDKN2A was more frequently altered in BM samples when compared to NSCLC primary samples (34% vs 14%, p = 0.003, q = 0.034). With regard to overrepresented gene sets, cell cycle pathway alterations were enriched in BM (56% vs 31%, p = 0.002, q = 0.022). BM samples had a significantly higher fraction of genome altered relative to the primary samples (p < 0.0001, q < 0.0001). After grouping patients based on type of CNS progression, we found that EGFR alterations were enriched in patients with leptomeningeal failures when compared to both patients without progression (42% vs 18%, p = 0.03, q = 0.93) and to patients with either local or regional progression (42% vs 19%, p = 0.03, q = 0.9). Conclusions: In the largest-ever assembled cohort of genomically-profiled NSCLC BM, we found significant enrichment for CDKN2A and cell cycle pathway alterations in BM compared to extracranial disease, as well as a higher fraction of genome altered, in BMs compared to matched primary tumor controls. We also observed EGFR alteration enrichment in patients who develop LMD, suggesting specific biologic underpinnings driving patterns of CNS failure. Further investigation into the role of systemic therapy and time course will elucidate potential mechanisms for CNS failure in patients with NSCLC.

Implementation Strategies to Increase Clinical Trial Enrollment in a Community-Academic Partnership and Impact on Hispanic Representation: An Interrupted Time Series Analysis

PURPOSE

Community-academic partnerships have the potential to improve access to clinical trials for under-represented minority patients who more often receive cancer treatment in community settings. In 2017, the Memorial Sloan Kettering (MSK) Cancer Center began opening investigator-initiated clinical trials in radiation oncology in targeted community-based partner sites with a high potential to improve diverse population accrual. This study evaluates the effectiveness of a set of implementation strategies for increasing overall community-based enrollment and the resulting proportional enrollment of Hispanic patients on trials on the basis of availability in community-based partner sites.

METHODS

An interrupted time series analysis evaluating implementation strategies was conducted from April 2018 to September 2021. Descriptive analysis ofHispanic enrollment on investigator-initiated randomized therapeutic radiation trials open at community-based sites was compared with those open only at themain academic center.

RESULTS

Overall, 84 patients were enrolled in clinical trials in the MSK Alliance, of which 48 (56%) identified as Hispanic. The quarterly patient enrollment pre- vs postimplementation increased from 1.39 (95% CI, -3.67 to 6.46) to 9.42 (95% CI, 2.05 to 16.78; P5 .017). In the investigator-initiated randomized therapeutic radiation trials open in the MSK Alliance, Hispanic representation was 11.5% and 35.9% in twometastatic trials and 14.2% in a proton versus photon trial. Inmatched trials open only at the main academic center, Hispanic representation was 5.6%, 6.0%, and 4.0%, respectively.

CONCLUSION

A combination of practice-level and physician-level strategies implemented at community-based partner sites was associated with increased clinical trial enrollment, which translated to improved Hispanic representation. This supports the role Q:2 of strategic community-academic partnerships in addressing disparities in clinical trial enrollment.

Semisupervised Training of a Brain MRI Tumor Detection Model Using Mined Annotations

Background Artificial intelligence (AI) applications for cancer imaging conceptually begin with automated tumor detection, which can provide the foundation for downstream AI tasks. However, supervised training requires many image annotations, and performing dedicated post hoc image labeling is burdensome and costly. Purpose To investigate whether clinically generated image annotations can be data mined from the picture archiving and communication system (PACS), automatically curated, and used for semisupervised training of a brain MRI tumor detection model. Materials and Methods In this retrospective study, the cancer center PACS was mined for brain MRI scans acquired between January 2012 and December 2017 and included all annotated axial T1 postcontrast images. Line annotations were converted to boxes, excluding boxes shorter than 1 cm or longer than 7 cm. The resulting boxes were used for supervised training of object detection models using RetinaNet and Mask region-based convolutional neural network (R-CNN) architectures. The best-performing model trained from the mined data set was used to detect unannotated tumors on training images themselves (self-labeling), automatically correcting many of the missing labels. After self-labeling, new models were trained using this expanded data set. Models were scored for precision, recall, and F1 using a held-out test data set comprising 754 manually labeled images from 100 patients (403 intra-axial and 56 extra-axial enhancing tumors). Model F1 scores were compared using bootstrap resampling. Results The PACS query extracted 31 150 line annotations, yielding 11 880 boxes that met inclusion criteria. This mined data set was used to train models, yielding F1 scores of 0.886 for RetinaNet and 0.908 for Mask R-CNN. Self-labeling added 18 562 training boxes, improving model F1 scores to 0.935 (P < .001) and 0.954 (P < .001), respectively. Conclusion The application of semisupervised learning to mined image annotations significantly improved tumor detection performance, achieving an excellent F1 score of 0.954. This development pipeline can be extended for other imaging modalities, repurposing unused data silos to potentially enable automated tumor detection across radiologic modalities. © RSNA, 2022 Online supplemental material is available for this article.

The Role of Ablative Radiotherapy in Older Adults With Limited Metastatic Disease

For patients with oligometastatic cancer, radiotherapy presents a promising avenue for achieving meaningful symptom relief and durable disease control. Data from recently published and ongoing randomized studies are helping to define the appropriate contexts for effective intervention with stereotactic ablative body radiotherapy (SABR) in the oligometastatic setting. Importantly, older adults represent a significant portion of patients with oligometastatic disease, yet often comprise a minority of patients in clinical trials. Moreover, older adults of the same chronologic age may have variable degrees of fitness and frailty. In this review, we highlight the specific challenges and considerations for the use of radiotherapy for older adults with oligometastatic disease-noting the importance of geriatric assessments in clinical decision-making about the appropriateness of SABR and other metastasis-directed therapies in this population. We then review data from existing trials, including a subset analysis of adverse events and survival estimates among older adults enrolled in the landmark SABR-COMET trial. Finally, we discuss future directions for research, including the need for focused clinical trials in older adult cohorts. Ultimately, a multidisciplinary approach is critical when carefully balancing the potential risks and benefits of this emerging treatment paradigm in the older adult population.

Recent Advances and Applications of Radiation Therapy for Brain Metastases

PURPOSE OF REVIEW

Radiation therapy (RT) is a mainstay of treatment for brain metastases from solid tumors. Treatment of these patients is complex and should focus on minimizing symptoms, preserving functional status, and prolonging survival.

RECENT FINDINGS

Whole-brain radiotherapy (WBRT) can lead to toxicity, and while it does reduce recurrence in the CNS, this has not been shown to provide a survival benefit. Recent advances focus on reducing the toxicity of WBRT or using more targeted radiation therapy. New paradigms including the use of proton RT for leptomeningeal metastases (LM) and stereotactic radiosurgery (SRS) before craniotomy hold promise in improving treatment efficacy and reducing toxicity. Omission or replacement of WBRT is often safe and the use of SRS is expanding to include patients with more lesions and preoperative RT. Proton RT holds promise for LM. Progress is being made in improving patient-centered outcomes and reducing toxicity for patients with brain metastases.

Clinical outcomes of dose-escalated hypofractionated external beam radiotherapy (5 Gy x 5 fractions) for spine metastasis

Purpose

Methods and Materials

Results

Conclusions

Automated and Clinically Optimal Treatment Planning for Cancer Radiotherapy

Each year, approximately 18 million new cancer cases are diagnosed worldwide, and about half must be treated with radiotherapy. A successful treatment requires treatment planning with the customization of penetrating radiation beams to sterilize cancerous cells without harming nearby normal organs and tissues. This process currently involves extensive manual tuning of parameters by an expert planner, making it a time-consuming and labor-intensive process, with quality and immediacy of critical care dependent on the planner's expertise. To improve the speed, quality, and availability of this highly specialized care, Memorial Sloan Kettering Cancer Center developed and applied advanced optimization tools to this problem (e.g., using hierarchical constrained optimization, convex approximations, and Lagrangian methods). This resulted in both a greatly improved radiotherapy treatment planning process and the generation of reliable and consistent high-quality plans that reflect clinical priorities. These improved techniques have been the foundation of high-quality treatments and have positively impacted over 4,000 patients to date, including numerous patients in severe pain and in urgent need of treatment who might have otherwise required longer hospital stays or undergone unnecessary surgery to control the progression of their disease. We expect that the wide distribution of the system we developed will ultimately impact patient care more broadly, including in resource-constrained countries.

Pan-cancer analysis of prognostic metastatic phenotypes

Although cancer is highly heterogeneous, all metastatic cancer is considered American Joint Committee on Cancer (AJCC) Stage IV disease. The purpose of this project was to redefine staging of metastatic cancer. Internal validation of nationally representative patient data from the National Cancer Database (n = 461 357; 2010-2013), and external validation using the Surveillance, Epidemiology and End Results database (n = 106 595; 2014-2015) were assessed using the concordance index for evaluation of survival prediction. A Cox proportional hazards model was used for overall survival by considering identified phenotypes (latent classes) and other confounding variables. Latent class analysis was performed for phenotype identification, where Bayesian information criterion (BIC) and sample-size-adjusted BIC were used to select the optimal number of distinct clusters. Kappa coefficients assessed external cluster validation. Latent class analysis identified five metastatic phenotypes with differences in overall survival (P < .0001): (Stage IVA) nearly exclusive bone-only metastases (n = 59 049, 12.8%; median survival 12.7 months; common in lung, breast and prostate cancers); (IVB) predominant lung metastases (n = 62 491, 13.5%; 11.4 months; common in breast, stomach, kidney, ovary, uterus, thyroid, cervix and soft tissue cancers); (IVC) predominant liver/lung metastases (n = 130 014, 28.2%; 7.0 months; common in colorectum, pancreatic, lung, esophagus and stomach cancers); (IVD) bone/liver/lung metastases predominant over brain (n = 61 004, 13.2%; 5.9 months; common in lung and breast cancers); and (IVE) brain/lung metastases predominant over bone/liver (n = 148 799, 32.3%; 5.7 months; lung cancer and melanoma). Long-term survivors were identified, particularly in Stages IVA-B. A pan-cancer nomogram model to predict survival (STARS: site, tumor, age, race, sex) was created, validated and provides 13% better prognostication than AJCC: 1-month concordance index of 0.67 (95% confidence interval [CI]: 0.66-0.67) vs 0.61 (95% CI: 0.60-0.61). STARS is simple, uses easily accessible variables, better prognosticates survival outcomes and provides a platform to develop novel metastasis-directed clinical trials.

Personalized Treatment Selection Leads to Low Rates of Local Salvage Therapy for Bone Metastases

PURPOSE

Local therapy for patients with nonspine bone metastases is evolving, with data supporting the use of single-fraction treatments, and more recently, showing possible benefit from stereotactic body radiation therapy (SBRT). However, the rate of local salvage therapy (LST) after each technique has not been characterized in real-world clinic settings where patients are selected at physician discretion. We examined rates of LST in patients with nonspine bone metastases.

METHODS AND MATERIALS

We reviewed records of RT for nonspine bone metastases at our institution from January 1, 2016, to December 31, 2018. We defined LST as the first occurrence of RT or surgery for oncologic progression to a bone metastasis after initial RT. Cumulative incidence functions for retreatment were generated. We conducted multivariate analysis to identify variables associated with LST.

RESULTS

A total of 1754 patients were analyzed, with median follow-up of 16.2 months (range, 0-36.8 months). Of all episodes of RT, 51.5% were multifraction external beam radiation therapy (EBRT), 7.0% were single-fraction EBRT, and 41.4% were SBRT. Altogether, 88 patients (5.0%) required LST, with an incidence at 6 months of 2.5%. Incidence of LST at 6 months was 2.1% for SBRT, 5.3% for single-fraction conventional regimens, and 2.4% for multifraction conventional regimens (P = .26). Patients of younger age, who had a higher Karnofsky performance status, and/or who had lesions in the pelvis had a higher risk of retreatment.

CONCLUSIONS

In this large institutional cohort, the rate of LST was low, with no difference between RT techniques. The findings indicated that SBRT for patients at high risk for treatment failure may reduce the rate of retreatment overall. When treatment modality was selected based on patient characteristics, rates of LST were lower than when treatment was randomly selected.

Novel Inpatient Radiation Oncology Consult Service Model Reduces Hospital Length of Stay

Palliative care and radiation therapy have played an expanding role in the management of patients with advanced cancers. Recent advances in our understanding of oligometastatic disease have led to increasing demand for familiarity with ablative techniques. Recognizing the demands of hospitalized patients for rapid access to care, we created an inpatient radiation oncology consult service (IROC) with consolidated expertise in palliative radiation and ablative techniques. In this quality improvement cohort study, we analyzed inpatient radiation oncology consults placed before and after IROC implementation and found that IROC led to increased delivery of specialty care and decreased hospital length of stay (median 8 days v 7 days, P = .005). This difference was most pronounced for patients for whom radiation therapy was indicated (14.5 v 11 days, P = .007). Our institutional experience demonstrates the value of recognizing metastatic disease as a distinct discipline and providing rapid access to palliative treatments for patients with advanced malignancies.

Should Postoperative Radiation for Long Bone Metastases Cover Part or All of the Orthopedic Hardware? Results of a Large Retrospective Analysis

Purpose

For patients with long bone metastases who undergo orthopedic stabilization surgery followed by radiotherapy (RT), it is unclear what extent of hardware coverage by the radiation field is needed for optimal tumor control.

Methods and Materials

Long bone metastases treated with surgical intervention followed by radiation between August 2011 to May 2019 from a single institution were reviewed. Local recurrence, defined as any in-bone recurrence, was identified by chart review. Accompanying demographic and treatment characteristics were recorded. Statistical analysis to evaluate factors associated with tumor recurrence included univariate analysis, multivariate analysis, and propensity score matching.

Results

Among 138 patients with 145 long bone metastases undergoing postoperative RT with a median follow-up of 29.5 months, 36 bone metastases experienced a local recurrence. Most patients (92%) were treated with conventional RT and the median delivered dose was 30 Gy (interquarile range, 20-30 Gy). On univariate analysis, whole hardware RT field coverage and higher dose (biologically effective dose 10 ≥39 Gy) were associated with reduced local recurrence (0.44 hazard ratio [HR]; 95% confidence interval [CI], 0.22%-0.86%; P = .017; 0.5 HR; 95% CI, 0.26%-0.96%; P = .038, respectively). Covariates of time from surgery to RT start, histology of primary tumor (categorized as resistant vs sensitive), intramedullary hardware placement, reaming procedure, and margin status did not reach statistical significance. To adjust for confounding effects, we also conducted a propensity score matched analysis which confirmed that whole hardware coverage was statistically associated with a decreased risk of recurrence on the matched dataset (0.24 HR; 95% CI, 0.07%-0.84%; P = .026).

Conclusions

In this analysis of mostly patients undergoing conventional radiation, coverage of the whole hardware was associated with reduced local recurrence for patients with long bone metastases, consistent with prior reports. Investigation of approaches to further reduce local recurrence, such as preoperative stereotactic radiation, may be warranted.

Long-term disease control and survival observed after stereotactic ablative body radiotherapy for oligometastatic breast cancer

PURPOSE

We examined the characteristics of breast cancer patients with oligometastases (OM) treated with stereotactic ablative body radiotherapy (SABR) to identify factors associated with local progression, distant metastasis progression, time to subsequent therapy, progression-free survival (PFS), and overall survival (OS).

METHODS

We retrospectively reviewed a single-institution database of patients treated with radiotherapy between 2008 and 2018 and identified 79 patients who received SABR to OM. Twenty-seven patients had genetic testing of metastatic tumors using an institutional targeted sequencing platform. Kaplan-Meier analysis, Cox regression, and competing risk models were used to compare clinical and genetic correlates with outcomes.

RESULTS

Median follow-up was 50 months (IQR: 29-66) with 67% of patients alive at the last follow-up. Of the 65% of patients who progressed, 82% progressed outside of the radiation field, 18% experienced local failure, and 80% had oligoprogression. Median OS was 86 months (IQR: 29-66), and PFS was 33 months (IQR: 10-38). Less than 5 years from diagnosis to SABR and triple-negative breast cancer (TNBC) were associated with worse OS. Advanced T stage, any prior chemotherapy, and TNBC were associated with worse PFS. Alterations in CEBPB, RB1, TBX3, PTEN, and CDK4 were associated with worse survival outcomes.

CONCLUSION

Long-term systemic disease control and survival can be achieved with SABR for oligometastatic breast cancer. Hormone receptor-positive patients with a long disease interval from initial diagnosis and limited systemic progression history may be ideal for SABR to all sites of disease.

Multidisciplinary consensus recommendations for the management of non-spine bone metastases: Results of a modified Delphi process in a community-academic partnership

e24092

Background: Local therapy for bone metastases is becoming increasingly complex, but national guidelines remain limited. We leveraged a community-academic partnership to develop consensus recommendations for multidisciplinary treatment of non-spine bone metastases which are generalizable to diverse practice settings. Methods: We convened a group of 15 physicians (9 radiation oncologists, 2 orthopaedic surgeons, 2 medical oncologists, 1 interventional radiologist, 1 interventional pain specialist) treating bone metastases across 4 institutions from Apr 2020-Feb 2021. We distributed a survey to identify questions warranting consensus development in the treatment of non-spine bone metastases. A literature review was conducted to inform answer statements, and evidence was rated using the Strength of Recommendation Taxonomy. A modified Delphi process was employed to reach consensus defined (a priori) as ³75% of respondents indicating “agree” or “strongly agree”. Results: A total of 16 questions were identified, including indications for multidisciplinary discussion or referral (n=4), appropriate use and duration of RT (n=4), and handling of systemic therapies during RT (n=5). After 2 rounds of modified Delphi process, consensus has been reached on 9 questions (see Table). Strength of Recommendation was rated A (1/9, 11%), B (5/9, 56%), or C (3/9, 33%). Conclusions: Our consensus process provides guidance for management of non-spine bone metastases that expands upon current guidelines. We also highlight areas where prospective trials are needed, including the role of RT prior to stabilization surgery and the selection of patients for ablative treatment. [Table: see text]

Cerebrospinal fluid circulating tumor cells as a predictive biomarker for proton craniospinal irradiation for leptomeningeal metastases

2011

Background: Leptomeningeal metastasis (LM) involves seeding of tumor cells to the cerebrospinal fluid (CSF) and the leptomeninges. Proton craniospinal irradiation (pCSI) has been shown to be potentially effective for patients with solid tumor LM. We evaluated whether CSF circulating tumor cells (CSF-CTC) and neuroimaging correlate with outcomes in patients with LM treated with pCSI. Methods: We reviewed a single-institution retrospective database of patients treated with pCSI for LM between 2018-2020 who had ≥ 3 months (mos.) follow-up and identified 58 patients. Pre-pCSI CSF-CTC using CellSearch and magnetic resonance imaging (MRI) data, and post-pCSI CSF-CTC nadir before initiation of new cancer-directed therapy were assessed. The optimal cutoff for pre-pCSI CSF-CTC was determined using maximally selected rank statistics. Kaplan Meier analysis was used to identify univariate correlates with CNS progression free survival (CNS PFS) and overall survival (OS), calculated from start of pCSI. Multivariate Cox proportional hazards modeling was used to test independence of univariate associations. Results: The median follow-up for patients who were censored (n = 15, 26%) was 15 mos. (interquartile range (IQR): 9 -21). Most patients were diagnosed with lung (n = 27, 47%) or breast cancer (n = 22, 38%). The median CNS PFS and OS were 6 mos. (IQR: 3 – 9) and 8 mos. (IQR: 5 – 18), respectively. Of the 49 patients with pre-pCSI CSF-CTCs analyzed, CSF-CTCs were identified in 43 (88%). Pre-pCSI CSF-CTC< 53/3mL was associated with improved CNS PFS (11.8 vs 6.0 mos., p = 0.01), and a trend toward improved OS (16.7 vs 7.7 mos., p = 0.08). On pre-pCSI MRI, patients with parenchymal brain metastases (n = 33, 57%) had worse OS (6.7 vs 12.7 mos., p = 0.01) but not CNS PFS. Patients with both brain and spine LM (n = 42, 72%) compared to those only one site or no visible disease (n = 16, 28%) showed worse CNS PFS (5.8 vs 7.5 mos., p = 0.03) and OS (7.7 vs 16.7 mos., p = 0.05). In a multivariate model, pre-pCSI CSF-CTC was significantly associated with CNS PFS (p = 0.03) while brain and spine LM on MRI was not (p = 0.20) No patient had an increase in CSF-CTC immediately post-pCSI, and in those with both detectable pre-pCSI CSF-CTCsand a post-pCSImeasurement(n = 29, 50%), the median decrease at nadir was 37/3mL (range: 0-200) occurring at a median of 1.6 mos. (range: 0.5 -5.2). A decrease in CSF-CTC > 37/3mL was associated with improved CNS PFS (7.1 vs 4.4 mos., p = 0.04) but not OS (12.5 vs.7.7 mos., p = 0.2). Conclusions: Proton CSI is an effective treatment for patients with solid tumor LM and can result in prolonged disease control in some patients. Lower CSF-CTC count prior to pCSI and larger changes after pCSI are predictive of survival outcomes, arguing for early pCSI intervention for solid tumor LMD. Early treatment escalation after pCSI can be considered for patients with high pre-pCSI CSF-CTC and a smaller nadir post-pCSI.

Accurate diagnosis of colorectal cancer based on histopathology images using artificial intelligence

BACKGROUND

Accurate and robust pathological image analysis for colorectal cancer (CRC) diagnosis is time-consuming and knowledge-intensive, but is essential for CRC patients' treatment. The current heavy workload of pathologists in clinics/hospitals may easily lead to unconscious misdiagnosis of CRC based on daily image analyses.

METHODS

Based on a state-of-the-art transfer-learned deep convolutional neural network in artificial intelligence (AI), we proposed a novel patch aggregation strategy for clinic CRC diagnosis using weakly labeled pathological whole-slide image (WSI) patches. This approach was trained and validated using an unprecedented and enormously large number of 170,099 patches, > 14,680 WSIs, from > 9631 subjects that covered diverse and representative clinical cases from multi-independent-sources across China, the USA, and Germany.

RESULTS

Our innovative AI tool consistently and nearly perfectly agreed with (average Kappa statistic 0.896) and even often better than most of the experienced expert pathologists when tested in diagnosing CRC WSIs from multicenters. The average area under the receiver operating characteristics curve (AUC) of AI was greater than that of the pathologists (0.988 vs 0.970) and achieved the best performance among the application of other AI methods to CRC diagnosis. Our AI-generated heatmap highlights the image regions of cancer tissue/cells.

CONCLUSIONS

This first-ever generalizable AI system can handle large amounts of WSIs consistently and robustly without potential bias due to fatigue commonly experienced by clinical pathologists. It will drastically alleviate the heavy clinical burden of daily pathology diagnosis and improve the treatment for CRC patients. This tool is generalizable to other cancer diagnosis based on image recognition.

Quantitative cerebrospinal fluid circulating tumor cells are a potential biomarker of response for proton craniospinal irradiation for leptomeningeal metastasis

BACKGROUND

Leptomeningeal metastasis (LM) involves cerebrospinal fluid (CSF) seeding of tumor cells. Proton craniospinal irradiation (pCSI) is potentially effective for solid tumor LM. We evaluated whether circulating tumor cells (CTCs) in the CSF (CTCCSF), blood (CTCblood), and neuroimaging correlate with outcomes after pCSI for LM.

METHODS

We describe a single-institution consecutive case series of 58 patients treated with pCSI for LM. Pre-pCSI CTCs, the change in CTC post-pCSI (Δ CTC), and MRIs were examined. Central nervous system progression-free survival (CNS-PFS) and overall survival (OS) from pCSI were determined using Kaplan Meier analysis, Cox proportional-hazards regression, time-dependent ROC analysis, and joint modeling of time-varying effects and survival outcomes.

RESULTS

The median CNS-PFS and OS were 6 months (IQR: 4-9) and 8 months (IQR: 5-13), respectively. Pre-pCSI CTCCSF < 53/3mL was associated with improved CNS-PFS (12.0 vs 6.0 months, P < .01). Parenchymal brain metastases (n = 34, 59%) on pre-pCSI MRI showed worse OS (7.0 vs 13 months, P = .01). Through joint modeling, CTCCSF was significantly prognostic of CNS-PFS (P < .01) and OS (P < .01). A Δ CTC-CSF≥37 cells/3mL, the median Δ CTC-CSF at nadir, showed improved CNS-PFS (8.0 vs 5.0 months, P = .02) and further stratified patients into favorable and unfavorable subgroups (CNS-PFS 8.0 vs 4.0 months, P < .01). No associations with CTCblood were found.

CONCLUSION

We found the best survival observed in patients with low pre-pCSI CTCCSF and intermediate outcomes for patients with high pre-pCSI CTCCSF but large Δ CTC-CSF. These results favor additional studies incorporating pCSI and CTCCSF measurement earlier in the LM treatment paradigm.

An Evaluation of the ACEP Guideline for Mild Head Injuries in Taiwan

Introduction

Traumatic brain injury (TBI) is an important issue in the emergency department. In the United States, the American College of Emergency Physicians (ACEP) published clinical guideline to select patients with mild head injuries for head computed tomography (CT) scans in 2008. The aim of this study was to identify the possible benefits of compliance with these guidelines for mild head injury patients in Taiwan.

Method

This was a secondary analysis on our previous study published for association of hypertension and head injuries. In our previous study, we collected data about 1290 patients with head injuries who received brain CT scans in the emergency department from September 2012 to August 2013 for a study regarding the association between head injury and hypertension. In present study, we subjected this data to further analysis to try to validate the ACEP clinical policy for mild head injuries.

Results

Of these 1,290 patients, 154 were found to have brain haemorrhage on the initial brain CT scan, and 5 were in need of neurosurgical intervention. A total of 859 patients met the ACEP guideline criteria, and 117 of these had brain haemorrhages. The sensitivity and specificity of the ACEP guideline to predict brain haemorrhage were 75.97% (95% confidence interval [CI], 68.44% to 82.48%) and 34.68% (95% CI, 31.91% to 37.53%), respectively. In predicting neurosurgical intervention, the sensitivity and specificity of the guideline were 100% (95% CI, 47.82% to 100%) and 33.54% (95% CI, 30.96% to 36.2%), respectively.

Conclusion

Although adoption of the ACEP clinical policy may reduce the number of brain CT scans in mild head injury patients who may need neurosurgical interventions, it is not a good selection tool in Taiwan.

Development of a millimetrically scaled biodiesel transesterification device that relies on droplet-based co-axial fluidics

In this study, we investigated a fluidic system that adheres to new concepts of energy production. To improve efficiency, cost, and ease of manufacture, a millimetrically scaled device that employs a droplet-based co-axial fluidic system was devised to complete alkali-catalyzed transesterification for biodiesel production. The large surface-to-volume ratio of the droplet-based system, and the internal circulation induced inside the moving droplets, significantly enhanced the reaction rate of immiscible liquids used here – soybean oil and methanol. This device also decreased the molar ratio between methanol and oil to near the stoichiometric coefficients of a balanced chemical equation, which enhanced the total biodiesel volume produced, and decreased the costs of purification and recovery of excess methanol. In this work, the droplet-based co-axial fluidic system performed better than other methods of continuous-flow production. We achieved an efficiency that is much greater than that of reported systems. This study demonstrated the high potential of droplet-based fluidic chips for energy production. The small energy consumption and low cost of the highly purified biodiesel transesterification system described conforms to the requirements of distributed energy (inexpensive production on a moderate scale) in the world.

[Effects of leucine on adipogenesis in 3T3-L1 preadipocytes during and after differentiation]

OBJECTIVE

To observe the effects of leucine on adipogenesis in 3T3-L1 preadipocyte during and after differentiation, and to investigate possible mechanisms.

METHODS

Respectively, 0.0 (control), 0.5, 1.0 and 2.0 mmol/L leucine was added in 3T3-L1 cells and cell proliferation was measured by MTT. Then, 3T3-L1 preadipocyte was induced to differentiate. Leucine was added during whole differentiation period, or after differentiation for 4 days. The cells were stained with Oil Red O dye to observe lipid droplet. The culture media were collected and used to determine glycerol contents. Meanwhile, protein expressions related to lypolytic enzymes, leptin signaling pathway were determined by Western blot.

RESULTS

MTT result showed that cell viabilities were (100.00±12.10)%, (102.73±12.38)%, (103.94±14.65)%, (108.70±5.05)% in 0.0, 0.5, 1.0 and 2.0 mmol/L leucine groups, respectively, there were no significant differences in cell proliferation among 4 groups (F=1.07, P=0.383). When 0.0, 0.5, 1.0 and 2.0 mmol/L leucine was added during differentiation, the relative number of lipid droplet was 1.00±0.06, 0.94±0.09, 0.82±0.08 and 0.79±0.04, respectively (F=11.74, P<0.001), and it was significantly lower in 1.0 and 2.0 mmol/L leucine groups than in control group (P=0.002 and P<0.001, respectively). There was no significant difference in lipid droplet when leucine was added after differentiation (F=0.16, P=0.924). When leucine was added during differentiation, the increment of glyceride contents in medium was (65.04 ± 11.75), (71.45 ± 23.71), (79.37 ± 17.63) and (110.32 ± 25.36) μmol/L, respectively (F=2.92, P=0.100). And it was significantly higher in 2.0 mmol/L leucine group (110.32 ± 25.36) μmol/L than in control group (65.04 ± 11.75) μmol/L (t=2.73, P=0.026). No significant difference of the increment of glyceride contents among 4 groups was observed when leucine was added after differentiation (F=0.80, P=0.528). Western blot results showed that leucine treatment during differentiation upregulated expression level of hormone-sensitive lipase phosphorylation (after 0.0 and 2.0 mmol/L leucine treatment,the protein levels were 1.00 ± 0.08 vs. 2.54 ± 0.27, P<0.001) , and downregulated the protein expression levels of perilipin A, leptin and leptin-related pathway, such as leptin receptor, Janus kinase 2 and suppressor of cytokine signaling-3 (after 0.0 and 2.0 mmol/L leucine was added, the protein levels were (1.00 ± 0.03) vs. (0.31 ± 0.07) , (1.00 ± 0.08) vs. (0.22±0.07) , (1.00±0.07) vs. (0.21 ± 0.04) , (1.00 ± 0.03) vs. (0.35 ± 0.05) , (1.00 ± 0.06) vs. (0.34 ± 0.05) , P<0.001). Leucine treatment after differentiation had no effects on these protein expressions (all P>0.05).

CONCLUSION

Leucine inhibits adipogenesis during 3T3-L1 preadipocyte differentiation by the regulation of lypolytic enzymes and leptin signaling pathway; however, leucine has no effect on adipogenesis when differentiation completed.

A portable microfluidic device for the rapid diagnosis of cancer metastatic potential which is programmable for temperature and CO2

If metastasis of lung cancer can be found and treated early, a victim might have an improved chance to prevail over it, but routine examinations such as chest radiography, computed tomography and biopsy cannot characterize the metastatic potential of lung cancer cells; critical diagnoses to define optimal therapeutic strategies are thus lost. We designed a portable microfluidic device for the rapid diagnosis of cancer metastatic potential. Featuring a micro system to control temperature and a bicarbonate buffered environment, our device discriminates a rate of surface detachment as an index of the migratory ability of cells cultured on pH-responsive chitosan. We labeled metastatic subpopulations of lung cancer cell lines, and verified that our device is capable of separating cells according to their metastatic ability. As only few cells are needed, a patient's specimen from biopsies, e.g. from fine-needle aspiration, can be processed on site to offer immediate information to physicians. We expect that our design will provide valuable information in pre-operative evaluations to assist the definition of therapeutic plans for lung cancer, as well as for metastatic tumors of other types.

A biocompatible open-surface droplet manipulation platform for detection of multi-nucleotide polymorphism

We present a novel and simple method to manipulate droplets applicable to an open-surface microfluidic platform. The platform comprised a control module for pneumatic droplets and a superhydrophobic polydimethylsiloxane (PDMS) membrane. With pneumatic suction to cause deflection of the flexible PDMS-based superhydrophobic membrane, the sample and reagent droplets on the membrane become transported and mixed. A facile one-step laser micromachining technique serves to fabricate a superhydrophobic surface; a contact angle of 150° and a hysteresis angle of 4° were achieved without chemical modification. Relative to previous open-surface microfluidic systems, this platform is capable of simultaneous and precise delivery of droplets in two-dimensional (2D) manipulation. Droplets were manipulated with suction, which avoided interference from an external driving energy (e.g. heat, light, electricity) to affect the bio-sample inside the droplets. Two common bio-samples, namely protein and DNA, verified the performance of the platform. Based on the experimental results, operations on protein can be implemented without adsorption on the surface of the platform. Another striking result is the visual screening for multi-nucleotide polymorphism with hybridization-mediated growth of gold-nanoparticle (AuNP) probes. The detection results are observable with the naked eye, without the aid of advanced instruments. The entire procedure only takes 5 min from the addition of the sample and reagent to obtaining the results, which is much quicker than the traditional method. The total sample volume consumed in each operation is only 10 μL, which is significantly less than what is required in a large system. According to this approach, the proposed platform is suitable for biological and chemical applications.

Predictors of early clinical deterioration after acute ischemic stroke

The measurements for predicting early deterioration of stroke patients is controversial. We studied laboratory measurements and previously identified risk factors to identify factors or predictors of early deterioration after stroke. A prospective observational study of 196 patients with first-time acute ischemic stroke was performed. Demographic data, patient histories, laboratory measurements, and initial stroke severity assessments were recorded. Patients with early deterioration in National Institutes of Health Stroke Scale scores (increase ≥3 points within 3 days) were defined as having stroke-in-evolution (SIE). Thirty patients were diagnosed with SIE. An initial National Institutes of Health Stroke Scale score of 12 or higher, a Glasgow Coma Scale score of 12 or lower, d-dimers more than 1000, or blood urea nitrogen/creatinine (BUN/Cr) ratio higher than 15 were more frequent in SIE patients. After multivariate analysis, only a BUN/Cr higher than 15 was independent predictor of SIE. These patients were 3.41-fold more likely to have SIE (P = .008). These findings suggest that BUN/Cr may be a novel predictor of SIE, potentially useful in emergency departments.

Pitching stabilization via caudal fin-wave propagation in a forward-sinking parrot cichlid (Cichlasoma citrinellum x Cichlasoma synspilum)

Caudal fin-wave propagation (CFP) is a commonly observed behavior in a fish but has been little investigated. Our objective is to understand the function of a CFP for a forward-sinking parrot cichlid that adopts a tilted-down swimming posture. We utilized stereoscopic digital particle-image velocimetry to measure the velocity fields in the wake of both the caudal fin and the pectoral fins and to evaluate the corresponding hydrodynamic forces. The tilted-down posture of this fish is inherently unstable because of the presence of the head-down pitching moment induced from the buoyant force of the body. The down-stroke of the pectoral fins results also in a head-down pitching moment that destabilizes the fish. Our results indicate that a CFP facilitates the pitching stabilization of a fish. In a forward-sinking parrot cichlid, a CFP produces periodic jets (CFP jets) that are oriented laterally and posterodorsally, which result in both thrust and negative lift that induce a head-up pitching moment. The CFP jets are initially trapped by the ventral part of the caudal fin, strengthened and reoriented by the dorsally propagating fin wave, and expelled near the dorsal part of the caudal fin.