Outcomes of a Single Isocenter Brain Multi-Metastases Linear Accelerator Delivered Stereotactic Radiosurgery (SRS)

PURPOSE/OBJECTIVE(S)

The management of brain metastases has evolved from using 2D whole brain radiotherapy (WBRT) to more complex techniques like stereotactic radiosurgery (SRS) for patients with limited disease. Long-term control of lesions is challenging with WBRT techniques but treating multiple lesions with traditional SRS, where each lesion is treated on its own isocenter, can be time-consuming and difficult on patients, especially those with claustrophobia. Single Isocenter Multiple Metastases (SIMM) SRS has emerged as an option to deliver ablative SRS doses simultaneously to multiple brain metastases using a single isocenter, thereby limiting the duration of treatments for patients. Though appealing, SIMM SRS adds technical complexity and could potentially lead to worse outcomes or more complications relative to traditional SRS treatments. Given the current paucity of clinical evidence supporting SIMM SRS, we sought to retrospectively review our institution's outcomes and complications for patients treated with SIMM SRS to determine the efficacy and safety of this approach in our hands.

MATERIALS/METHODS

Patients treated at our institution with SIMM SRS with at least one post-treatment brain MRI were identified. Date on patient clinical characteristics, planning, and treatment characteristics, and outcomes were retrospectively collected. Post-treatment tumor control was evaluated with follow-up MRI imaging based on RANO criteria. Correlation between tumor control and toxicity was done by assessing radiation doses, PTV coverage, and normal brain V12 constraints.

RESULTS

A total of 27 patients received SIMM SRS from January 2015 to February 2022. The median age at first SIMM SRS was 61 (range: 38-87). The most common disease sites were lung (63.0%), breast (18.5%), and GI (7.4%). The 27 patients had 47 SIMM SRS treatments of 163 lesions total. The median number of lesions treated per isocenter was 3 (range: 2-9). 5 patients had 2 SIMM SRS isocenters treated on the same day, treating clusters of lesions (ranging from 5-11 lesions treated on that day). The most common locations involved were frontal, cerebellar, and parietal lobes (32.52%, 21.47%, and 15.34%). The modal dose was 22 Gy (range: 18-24 Gy). Median OS from initial primary diagnosis was 23.23 months, and 9.92 months after the first SIMM SRS treatment. The median imaging follow-up was 9.8 months per lesion, and the local control rate was 95.03%. 2 lesions (1.23%) developed radiation necrosis and the median time to RT necrosis among those lesions was 5.7 months after treatment.

CONCLUSION

The utilization of SIMM SRS demonstrates acceptable efficacy and safety as it has been implemented at our institution. Further studies to evaluate this planning modality are warranted to establish suitable candidates for SIMM SRS as well as evaluate the long-term outcomes for these patients.

Technology Usage and Impacts by COVID-19 among Patients in a Radiation Oncology Clinic

Purpose/Objective(s)

Mobile devices provide platforms for consistent and real time symptom tracking for cancer patients, allowing for better symptom reporting and more timely interventions. There is limited research investigating barriers to adoption within the oncology setting and COVID-19 impacts on patent willingness to use health technology. Understanding these issues is key to successful development and implementation. We designed a survey to assess patient willingness and barriers to using mobile devices to report/track symptoms (e-report).

Materials/Methods

Two cohorts of adult patients completed a 21-question anonymized survey. The survey was administered to clinic patients before (PRE) and 18mo after (POST) the start of the COVID pandemic. Three additional questions were added to POST survey to investigate impacts from COVID. Demographics, technology usage, willingness to report data, barriers to utilization, and changes due to COVID were evaluated using descriptive statistics. Predictors of willingness to e-report, barriers to use, and changes due to the COVID-19 pandemic were analyzed using univariate and multivariate logistic regression (MVA).

Results

318 patients completed the survey (PRE= 144 patients; POST= 174 patients) with mean age 65y, 75% Caucasian, 55% male. Altogether, 75% used a smart phone (PRE=66.7%; POST=81.3%; p 0.003), 90% reported home internet access (PRE=87.5%; POST=91.4%; p 0.259), 86% used a computer (PRE=79.2%; POST=90.8%; p 0.004), and 26% used a wearable health tracker (PRE 25.7%; POST 26.4%; p 0.881). On MVA, age>65 (OR 0.32; p 0.001), annual income>50K (OR 2.16; p 0.032), smart phone ownership (OR 4.07; p 0.000), and new/current patient status (OR 2.15; p 0.020) were all significant factors impacting willingness to e- report. Limited tech literacy (p 0.024) and time commitment (p 0.048) were the only significant barriers. Privacy as a barrier was greater in PRE vs POST cohort (OR 2.3 vs OR 1.1) trending toward significance. Nearly all modes of tech usage were greater in POST vs PRE cohort. POST cohort was significantly more willing to e- report (81.1% vs 69.1%; OR 1.91; p 0.016). This remained significant on MVA after adjusting for age, concern for privacy, tech literacy, and patient status (OR 1.88; p 0.026). Furthermore, 51% of POST cohort reported the pandemic directly influenced their willingness to e-report (40% more, 11% less).

Conclusion

Radiation oncology patients are willing to use mobile technology to report symptoms. Willingness increases with decreasing age, increasing annual income, smartphone ownership, and new/current patient status. Significant barriers include tech literacy and time commitment. Post-pandemic patients are more willing to e-report and list fewer barriers. The COVID-19 pandemic appears to have had a positive impact on technology usage by patients. Efforts to develop and test mobile applications for this population are justified.

A collaboration on teaching communication by text

Background

Since the start of the pandemic, text‐based communication with patients has become increasingly common. Leicester Medical School introduced experiential teaching in this field in 2014 but identified a need to develop teaching on the key skills required for effective consultations.

Shout 85258 offers a text messaging support service for anyone who is struggling with their mental health. They have developed an evidence‐based training programme enabling volunteers to deliver quality crisis support via the medium of text messaging.

Approach

Leicester Medical School and Shout 85258 collaborated, developing a small group teaching session for delivery to second‐year medical students. The training programme and framework developed by Shout 85258 was used as the basis for a 1.5‐hour session with didactic teaching and experiential role play. It was hoped that the collaboration would raise the profile of Shout 85258 in the student body.

Evaluation

The students enjoyed the mixture of didactic teaching and role play. They saw the relevance of the topic and recognised the key difficulties of text‐based consultations such as in rapport building.

Tutors valued the structure of the session and the framework provided.

The session raised the profile of Shout 85258 amongst students and tutors. Further evaluation is needed to measure changes in the use of the service or volunteering by students following the session.

Implications

Text‐based consultation is an increasingly important area of communication in health care.

Collaborating with a charitable organisation allowed sharing of established best practice in this area and raised the profile of the charity within the student body.

Mobilan: a recombinant adenovirus carrying Toll-like receptor 5 self-activating cassette for cancer immunotherapy

Toll-like receptor 5 (TLR5) is considered an attractive target for anticancer immunotherapy. TLR5 agonists, bacterial flagellin and engineered flagellin derivatives, have been shown to have potent antitumor and metastasis-suppressive effects in multiple animal models and to be safe in both animals and humans. Anticancer efficacy of TLR5 agonists stems from TLR5-dependent activation of nuclear factor-κB (NF-κB) that mediates innate and adaptive antitumor immune responses. To extend application of TLR5-targeted anticancer immunotherapy to tumors that do not naturally express TLR5, we created an adenovirus-based vector for intratumor delivery, named Mobilan that drives expression of self-activating TLR5 signaling cassette comprising of human TLR5 and a secreted derivative of Salmonella flagellin structurally analogous to a clinical stage TLR5 agonist, entolimod. Co-expression of TLR5 receptor and agonist in Mobilan-infected cells established an autocrine/paracrine TLR5 signaling loop resulting in constitutive activation of NF-κB both in vitro and in vivo. Injection of Mobilan into primary tumors of the prostate cancer-prone transgenic adenocarcinoma of the mouse prostate (TRAMP) mice resulted in a strong induction of multiple genes involved in inflammatory responses and mobilization of innate immune cells into the tumors including neutrophils and NK cells and suppressed tumor progression. Intratumoral injection of Mobilan into subcutaneously growing syngeneic prostate tumors in immunocompetent hosts improved animal survival after surgical resection of the tumors, by suppression of tumor metastasis. In addition, vaccination of mice with irradiated Mobilan-transduced prostate tumor cells protected mice against subsequent tumor challenge. These results provide proof-of-concept for Mobilan as a tool for antitumor vaccination that directs TLR5-mediated immune response toward cancer cells and does not require identification of tumor antigens.

Fistulizing Epstein-Barr virus-positive plasmablastic lymphoma in an HIV-positive man

Plasmablastic lymphoma (PBL) is an unusual subtype of non-Hodgkin lymphoma recently classified as a diffuse immunoblastic lymphoma with a plasma-cell immunophenotype. Originally described in the oral cavity of HIV-positive patients, it has also been recognized to occur rarely at other sites. We describe a previously unreported fistulizing presentation of Epstein-Barr virus (EBV)-positive PBL, reviewing its association with HIV-1 infection and its importance as an AIDS-defining malignancy.

The vapor-phase multi-stage CMD test for characterizing contaminant mass discharge associated with VOC sources in the vadose zone: Application to three sites in different lifecycle stages of SVE operations

Vapor-phase multi-stage contaminant mass discharge (CMD) tests were conducted at three field sites to measure mass discharge associated with contaminant sources located in the vadose zone. The three sites represent the three primary stages of the soil vapor extraction (SVE) operations lifecycle-pre/initial-SVE, mid-lifecycle, and near-closure. A CMD of 32g/d was obtained for a site at which soil vapor SVE has been in operation for approximately 6years, and for which mass removal is currently in the asymptotic stage. The contaminant removal behavior exhibited for the vapor extractions conducted at this site suggests that there is unlikely to be a significant mass of non-vapor-phase contaminant (e.g., DNAPL, sorbed phase) remaining in the advective domains, and that most remaining mass is likely located in poorly accessible domains. Given the conditions for this site, this remaining mass is hypothesized to be associated with the low-permeability (and higher water saturation) region in the vicinity of the saturated zone and capillary fringe. A CMD of 25g/d was obtained for a site wherein SVE has been in operation for several years but concentrations and mass-removal rates are still relatively high. A CMD of 270g/d was obtained for a site for which there were no prior SVE operations. The behavior exhibited for the vapor extractions conducted at this site suggest that non-vapor-phase contaminant mass (e.g., DNAPL) may be present in the advective domains. Hence, the asymptotic conditions observed for this site most likely derive from a combination of rate-limited mass transfer from DNAPL (and sorbed) phases present in the advective domain as well as mass residing in lower-permeability ("non-advective") regions. The CMD values obtained from the tests were used in conjunction with a recently developed vapor-discharge tool to evaluate the impact of the measured CMDs on groundwater quality.

Using vapor phase tomography to measure the spatial distribution of vapor concentrations and flux for vadose-zone VOC sources

A test was conducted at a chlorinated-solvent contaminated site in Tucson, AZ, to evaluate the effectiveness of vapor-phase tomography (VPT) for characterizing the distribution of volatile organic contaminants (VOC) in the vadose zone. A soil vapor extraction (SVE) system has been in operation at the site since 2007. Vapor concentration and vacuum pressure were measured at four different depths in each of the four monitoring wells surrounding the extraction well. The test provided a 3D characterization of local vapor concentrations under induced-gradient conditions. Permeability data obtained from analysis of borehole logs were used along with pressure and the vapor-concentration data to determine VOC mass flux within the test domain. A region of higher mass flux was identified in the deepest interval of the S-SW section of the domain, indicating the possible location of a zone with greater contaminant mass. These results are consistent with the TCE-concentration distribution obtained from sediment coring conducted at the site. In contrast, the results of a standard soil gas survey did not indicate the presence of a zone with greater contaminant mass. These results indicate that the VPT test provided a robust characterization of VOC concentration and flux distribution at the site.

Weak antilocalization of high mobility holes in a strained germanium quantum well heterostructure

We present the observation of weak antilocalization due to the Rashba spin-orbit interaction, through magnetoresistance measurements performed at low temperatures and low magnetic fields on a high mobility (777,000 cm(2) V(-1) s(-1)) p-Ge/SiGe quantum well heterostructure. The measured magnetoresistance over a temperature range of 0.44 to 11.2 K shows an apparent transition from weak localization to weak antilocalization. The temperature dependence of the zero field conductance correction is indicative of weak localization using the simplest model, despite the clear existence of weak antilocalization. The Rashba interaction present in this material, and the absence of the un-tuneable Dresselhaus interaction, indicates that Ge quantum well heterostructures are highly suitable for semiconductor spintronic applications, particularly the proposed spin field effect transistor.

Evidence for a time-dependent association between FOLR1 expression and survival from ovarian carcinoma: implications for clinical testing. An Ovarian Tumour Tissue Analysis consortium study

BACKGROUND

Folate receptor 1 (FOLR1) is expressed in the majority of ovarian carcinomas (OvCa), making it an attractive target for therapy. However, clinical trials testing anti-FOLR1 therapies in OvCa show mixed results and require better understanding of the prognostic relevance of FOLR1 expression. We conducted a large study evaluating FOLR1 expression with survival in different histological types of OvCa.

METHODS

Tissue microarrays composed of tumour samples from 2801 patients in the Ovarian Tumour Tissue Analysis (OTTA) consortium were assessed for FOLR1 expression by centralised immunohistochemistry. We estimated associations for overall (OS) and progression-free (PFS) survival using adjusted Cox regression models. High-grade serous ovarian carcinomas (HGSC) from The Cancer Genome Atlas (TCGA) were evaluated independently for association between FOLR1 mRNA upregulation and survival.

RESULTS

FOLR1 expression ranged from 76% in HGSC to 11% in mucinous carcinomas in OTTA. For HGSC, the association between FOLR1 expression and OS changed significantly during the years following diagnosis in OTTA (Pinteraction=0.01, N=1422) and TCGA (Pinteraction=0.01, N=485). In OTTA, particularly for FIGO stage I/II tumours, patients with FOLR1-positive HGSC showed increased OS during the first 2 years only (hazard ratio=0.44, 95% confidence interval=0.20-0.96) and patients with FOLR1-positive clear cell carcinomas (CCC) showed decreased PFS independent of follow-up time (HR=1.89, 95% CI=1.10-3.25, N=259). In TCGA, FOLR1 mRNA upregulation in HGSC was also associated with increased OS during the first 2 years following diagnosis irrespective of tumour stage (HR: 0.48, 95% CI: 0.25-0.94).

CONCLUSIONS

FOLR1-positive HGSC tumours were associated with an increased OS in the first 2 years following diagnosis. Patients with FOLR1-negative, poor prognosis HGSC would be unlikely to benefit from anti-FOLR1 therapies. In contrast, a decreased PFS interval was observed for FOLR1-positive CCC. The clinical efficacy of FOLR1-targeted interventions should therefore be evaluated according to histology, stage and time following diagnosis.

Evidence for a time-dependent association between FOLR1 expression and survival from ovarian carcinoma: implications for clinical testing. An Ovarian Tumour Tissue Analysis consortium study

BACKGROUND

Folate receptor 1 (FOLR1) is expressed in the majority of ovarian carcinomas (OvCa), making it an attractive target for therapy. However, clinical trials testing anti-FOLR1 therapies in OvCa show mixed results and require better understanding of the prognostic relevance of FOLR1 expression. We conducted a large study evaluating FOLR1 expression with survival in different histological types of OvCa.

METHODS

Tissue microarrays composed of tumour samples from 2801 patients in the Ovarian Tumour Tissue Analysis (OTTA) consortium were assessed for FOLR1 expression by centralised immunohistochemistry. We estimated associations for overall (OS) and progression-free (PFS) survival using adjusted Cox regression models. High-grade serous ovarian carcinomas (HGSC) from The Cancer Genome Atlas (TCGA) were evaluated independently for association between FOLR1 mRNA upregulation and survival.

RESULTS

FOLR1 expression ranged from 76% in HGSC to 11% in mucinous carcinomas in OTTA. For HGSC, the association between FOLR1 expression and OS changed significantly during the years following diagnosis in OTTA (Pinteraction=0.01, N=1422) and TCGA (Pinteraction=0.01, N=485). In OTTA, particularly for FIGO stage I/II tumours, patients with FOLR1-positive HGSC showed increased OS during the first 2 years only (hazard ratio=0.44, 95% confidence interval=0.20-0.96) and patients with FOLR1-positive clear cell carcinomas (CCC) showed decreased PFS independent of follow-up time (HR=1.89, 95% CI=1.10-3.25, N=259). In TCGA, FOLR1 mRNA upregulation in HGSC was also associated with increased OS during the first 2 years following diagnosis irrespective of tumour stage (HR: 0.48, 95% CI: 0.25-0.94).

CONCLUSIONS

FOLR1-positive HGSC tumours were associated with an increased OS in the first 2 years following diagnosis. Patients with FOLR1-negative, poor prognosis HGSC would be unlikely to benefit from anti-FOLR1 therapies. In contrast, a decreased PFS interval was observed for FOLR1-positive CCC. The clinical efficacy of FOLR1-targeted interventions should therefore be evaluated according to histology, stage and time following diagnosis.

Measuring spatial variability of vapor flux to characterize vadose-zone VOC sources: flow-cell experiments

A method termed vapor-phase tomography has recently been proposed to characterize the distribution of volatile organic contaminant mass in vadose-zone source areas, and to measure associated three-dimensional distributions of local contaminant mass discharge. The method is based on measuring the spatial variability of vapor flux, and thus inherent to its effectiveness is the premise that the magnitudes and temporal variability of vapor concentrations measured at different monitoring points within the interrogated area will be a function of the geospatial positions of the points relative to the source location. A series of flow-cell experiments was conducted to evaluate this premise. A well-defined source zone was created by injection and extraction of a non-reactive gas (SF6). Spatial and temporal concentration distributions obtained from the tests were compared to simulations produced with a mathematical model describing advective and diffusive transport. Tests were conducted to characterize both areal and vertical components of the application. Decreases in concentration over time were observed for monitoring points located on the opposite side of the source zone from the local-extraction point, whereas increases were observed for monitoring points located between the local-extraction point and the source zone. The results illustrate that comparison of temporal concentration profiles obtained at various monitoring points gives a general indication of the source location with respect to the extraction and monitoring points.

Characterizing long-term contaminant mass discharge and the relationship between reductions in discharge and reductions in mass for DNAPL source areas

The objective of this study was to characterize the temporal behavior of contaminant mass discharge, and the relationship between reductions in contaminant mass discharge and reductions in contaminant mass, for a very heterogeneous, highly contaminated source-zone field site. Trichloroethene is the primary contaminant of concern, and several lines of evidence indicate the presence of organic liquid in the subsurface. The site is undergoing groundwater extraction for source control, and contaminant mass discharge has been monitored since system startup. The results show a significant reduction in contaminant mass discharge with time, decreasing from approximately 1 to 0.15 kg/d over five years. Two methods were used to estimate the mass of contaminant present in the source area at the initiation of the remediation project. One was based on a comparison of two sets of core data, collected 3.5 years apart, which suggests that a significant (~80%) reduction in aggregate sediment-phase TCE concentrations occurred between sampling events. The second method was based on fitting the temporal contaminant mass discharge data with a simple exponential source-depletion function. Relatively similar estimates, 784 and 993 kg, respectively, were obtained with the two methods. These data were used to characterize the relationship between reductions in contaminant mass discharge (CMDR) and reductions in contaminant mass (MR). The observed curvilinear relationship exhibits a reduction in contaminant mass discharge essentially immediately upon the initiation of mass reduction. This behavior is consistent with a system wherein significant quantities of mass are present in hydraulically poorly accessible domains for which mass removal is influenced by rate-limited mass transfer. The results obtained from the present study are compared to those obtained from other field studies to evaluate the impact of system properties and conditions on mass-discharge and mass-removal behavior. The results indicate that factors such as domain scale, hydraulic-gradient status (induced or natural), and flushing-solution composition had insignificant impact on the CMDR-MR profiles and thus on underlying mass-removal behavior. Conversely, source-zone age, through its impact on contaminant distribution and accessibility, was implicated as a critical factor influencing the nature of the CMDR-MR relationship.

History of Injury and Violence as public health problems and emergence of the National Center for Injury Prevention and Control at CDC

Injuries and violence are among the oldest health problems facing humans. Only within the past 50 years, however, has the problem been addressed with scientific rigor using public health methods. The field of injury control began as early as 1913, but wasn't approached systematically or epidemiologically until the 1940s and 1950s. It accelerated rapidly between 1960 and 1985. Coupled with active federal and state interest in reducing injuries and violence, this period was marked by important medical, scientific, and public health advances. The National Center for Injury Prevention and Control (NCIPC) was an outgrowth of this progress and in 2012 celebrated its 20th anniversary. NCIPC was created in 1992 after a series of government reports identified injury as one of the most important public health problems facing the nation. Congressional action provided the impetus for the creation of NCIPC as the lead federal agency for non-occupational injury and violence prevention. In subsequent years, NCIPC and its partners fostered many advances and built strong capacity. Because of the tragically high burden and cost of injuries and violence in the United States and around the globe, researchers, practitioners, and decision makers will need to redouble prevention efforts in the next 20 years. This article traces the history of injury and violence prevention as a public health priority-- including the evolution and current structure of the CDC's National Center for Injury Prevention and Control.

Incidence of major clinical outcomes in a cohort of Ugandan and Zimbabwean women with HIV-1 infection followed from seroconversion

We conducted a prospective cohort study of 306 HIV-1-infected women, followed from seroconversion for median 6.4 years in Uganda (UG) and Zimbabwe (ZM) to describe the incidence of major clinical outcomes (MCOs), defined as World Health Organization stage 4 conditions and any tuberculosis (TB). In Uganda, 19 MCOs occurred in 13 participants at median 4.6 years and a median CD4 count of 213 cells/mm(3). In Zimbabwe, 29 MCOs occurred in 27 participants at median 4.0 years (P < 0.001 versus UG) and median CD4 count of 219 cells/mm(3) (P = 0.83 versus UG). MCO incidence was not statistically different (UG: 2.82 cases/100 person-years versus ZM: 2.45; P = 0.64) except for TB (UG: 0.59 versus ZM: 2.02 cases/100 person-years; P = 0.02). This significant difference in TB incidence is primarily due to a TB screening and isoniazid prevention therapy programme that was implemented in Uganda, but not in Zimbabwe, highlighting the importance of integrated TB screening and treatment within HIV programmes.

Paediatric traumatic out-of-hospital cardiac arrests in Melbourne, Australia

INTRODUCTION

Many consider attempted resuscitation for traumatic out-of-hospital cardiac arrest (OHCA) futile. This study aims to describe the characteristics and profile of paediatric traumatic OHCA.

METHODS

The Victorian Ambulance Cardiac Arrest Registry (VACAR) was used to identify all trauma related cases of OHCA in patients aged less than 16 years of age. Cases were linked with their coronial findings.

RESULTS

Between 2000 and 2009, EMS attended 33,722 OHCAs including 2187 adult traumatic OHCAs. There were 538 (1.6%) OHCAs in children less than 16 years of age of which n=64 were due to trauma. The median age (IQR) of paediatric traumatic OHCA was 7 (4.5-13) years and 44 were male (69%). Bystander CPR was performed in 22 cases (34.4%). The first recorded rhythm by EMS was asystole seen in 42 (66%), PEA in 14 (22%) cases and VF in 2 cases (3%). Cardiac output was present in 7 (11%) cases who subsequently had an EMS witnessed OHCA. EMS attempted resuscitation in 35 (55%) patients of whom 7 (20%) achieved ROSC and were transported, and 1 (3%) survived to hospital discharge with severe neurological sequelae; 14(40%) were transported with CPR of whom none survived. Coronial cause of death was multiple injuries in 35%, head injury in 33%, head and neck injury in 10%, chest injuries in 10% and other causes (12%).

CONCLUSIONS

Traumatic aetiology of OHCA when compared to the incidence of adult traumatic OHCAs is uncommon. Resuscitation efforts are seldom effective and associated with poor neurological outcome.