Significance of alterations in DNA damage repair (DDR) genes in advanced biliary cancers (ABCs) treated with second-line active-symptom-control (ASC) alone or ASC with oxaliplatin/5-FU chemotherapy (ASC+FOLFOX) in the randomised phase III, multicentre, open-label ABC-06 trial

593

Background: The ABC-06 clinical trial established ASC+mFOLFOX as the standard of care treatment after Cisplatin and Gemcitabine (CisGem) for ABC. Translational research explored the role of alterations in DDR-related genes in the context of the ABC-06 clinical trial. Methods: Translational research using samples collected from the ABC-06 trial included all recruited patients with tissue sample containing >20% tumour cellularity with sufficient DNA extracted for analysis. Primary objective: assess the prevalence of somatic mutations within DDR genes in ABC. Secondary objectives: explore the impact of somatic mutations in DDR genes on: A) Patient’s response to platinum-based chemotherapy (predictive biomarker): 1) Retrospectively, using progression-free survival (PFS) data from 1st-line chemotherapy and 2) Prospectively, by assessing the impact on PFS/radiological response to 2nd-line FOLFOX (vs. control) and B) Overall survival (prognostic biomarker). Survival analysis was performed with Kaplan-Meier and Cox Regression. Results: Of 162 pts randomised, 83 had a sample available for analysis; of these, analysis failed in 24 despite >20% tumour content. Thus, a total of 59 patients (30 ASC arm, 29 ASC+FOLFOX arm) were eligible for this translational analysis: male 50.85%, metastatic 77.97%, intrahepatic cholangiocarcinoma 47.46%, adenocarcinoma 91.53%, median age 65.84 years (95% CI 63.36-68.91). Pathogenic mutations in DDR genes were identified in 22 patients (37.29%). PFS did not vary depending on the DDR-gene alterations either in the first-line setting with CisGem (n=59; 8.73 months vs 8.18 months; p-value 0.155) or with second-line FOLFOX (n=29; 3.19 months vs 3.45 months; p-value 0.098). Median OS for DDR-altered patients was 4.59 months (95% CI 2.17-5.88) (vs 7.23 months (95% CI 5.45-8.28) for DDR-wild-type); HR 2.63 (95% CI 1.48-4.67); p-value 0.001. This prognostic impact was confirmed when the prognostic model was adjusted for treatment arm and stratification factors (HR 3.75 (95% CI 1.99-7.09); p-value <0.001). Conclusions: For ABC patients, the presence of DDR-related gene pathogenic mutations are present in around one third of patients. Despite presence of DDR-mutations having a negative prognostic impact, their predictive role is not confirmed either for first-line CisGem or second-line FOLFOX. Clinical trial information: NCT01926236 .

Surgical and Oncological Score to Estimate the Survival Benefit of Resection and Chemoradiotherapy in Elderly (≥70 Years) Glioblastoma Patients: A Preliminary Analysis Authors

AIMS

Elderly patients with glioblastoma are perceived to face a poor prognosis with perceptions surrounding older age and a relative lack of randomized data contributing. This study aimed to evaluate survival prognosticators in elderly glioblastoma patients to more accurately guide their treatment.

METHOD

The records of 169 elderly (≥70 years) patients with a new diagnosis of glioblastoma who had undergone neurosurgical intervention were retrospectively examined for patient sex, age, performance status, comorbidities, MGMT promoter methylation, surgical intervention and chemoradiation regime. The adjusted survival impact of these factors was determined using Cox proportional hazards model and used to devise a two-stage scoring system to estimate patient survival at the stage of surgical (Elderly Glioblastoma Surgical Score, EGSS) and oncological management (Elderly Glioblastoma Oncological Score, EGOS).

RESULTS

The median overall survival (mOS) of the cohort was 28.8 weeks. Gross-total and subtotal resection were associated with improved survival compared to biopsy alone (respective mOS 65.3 and 28.1 vs 15.7 weeks, p&lt;0.001). Hypofractionated radiotherapy (40Gy in 15 fractions) with Temozolomide was non-inferior to the Stupp protocol, p=0.72. Exploratory subgroup analysis revealed a significant benefit of Temozolomide-based approaches in MGMT-methylated patients as well as a trend towards improved survival in MGMT-unmethylated patients. Our EGSS and EGOS scores successfully estimated survival in this retrospective cohort with 65% and 73% accuracy.

CONCLUSION

Where appropriate and safe, elderly glioblastoma patients may benefit from surgical resection and combined chemoradiotherapy with Temozolomide. The proposed EGSS and EGOS scores take into account important prognostic factors to help guide which patients should receive such treatment.

Risk of second brain tumour after radiotherapy for pituitary adenoma or craniopharyngioma: a retrospective, multicentre, cohort study of 3679 patients with long-term imaging surveillance

BACKGROUND

Radiotherapy is a valuable treatment in the management algorithm of pituitary adenomas and craniopharyngiomas. However, the risk of second brain tumour following radiotherapy is a major concern. We assessed this risk using non-irradiated patients with the same primary pathology and imaging surveillance as controls.

METHODS

In this multicentre, retrospective cohort study, 4292 patients with pituitary adenoma or craniopharyngioma were identified from departmental registries at six adult endocrine centres (Birmingham, Oxford, Leeds, Leicester, and Bristol, UK and Ferrara, Italy). Patients with insufficient clinical data, known genetic predisposition to or history of brain tumour before study entry (n=532), and recipients of proton beam or stereotactic radiotherapy (n=81) were excluded. Data were analysed for 996 patients exposed to 2-dimensional radiotherapy, 3-dimensional conformal radiotherapy, or intensity-modulated radiotherapy, and compared with 2683 controls.

FINDINGS

Over 45 246 patient-years, second brain tumours were reported in 61 patients (seven malignant [five radiotherapy, two controls], 54 benign [25 radiotherapy, 29 controls]). Radiotherapy exposure and older age at pituitary tumour detection were associated with increased risk of second brain tumour. Rate ratio for irradiated patients was 2·18 (95% CI 1·31-3·62, p<0·0001). Cumulative probability of second brain tumour was 4% for the irradiated and 2·1% for the controls at 20 years.

INTERPRETATION

Irradiated adults with pituitary adenoma or craniopharyngioma are at increased risk of second brain tumours, although this risk is considerably lower than previously reported in studies using general population controls with no imaging surveillance. Our data clarify an important clinical question and guide clinicians when counselling patients with pituitary adenoma or craniopharyngioma on the risks and benefits of radiotherapy.

FUNDING

Pfizer.

Surgical and oncological score to estimate the survival benefit of resection and chemoradiotherapy in elderly (≥70 years) glioblastoma patients: a preliminary analysis

Background

Elderly patients with glioblastoma are perceived to face a poor prognosis with perceptions surrounding older age and a relative lack of randomized data contributing. This study evaluated survival prognosticators in elderly glioblastoma patients to more accurately guide their treatment.

Methods

The records of 169 elderly (≥70 years) patients with a new diagnosis of glioblastoma who had undergone neurosurgical intervention were retrospectively examined for patient sex, age, performance status, comorbidities, MGMT promoter methylation, surgical intervention, and chemoradiation regime. The adjusted survival impact of these factors was determined using Cox proportional hazards model and used to devise a two-stage scoring system to estimate patient survival at the stage of surgical (Elderly Glioblastoma Surgical Score, EGSS) and oncological management (Elderly Glioblastoma Oncological Score, EGOS).

Results

The median overall survival (mOS) of the cohort was 28.8 weeks. Gross-total and subtotal resection were associated with improved survival compared to biopsy alone (respective mOS 65.3 and 28.1 vs 15.7 weeks, P < .001). Hypofractionated radiotherapy (40Gy in 15 fractions) with Temozolomide was noninferior to the Stupp protocol, P = .72. Exploratory subgroup analysis revealed a significant benefit of Temozolomide-based approaches in MGMT-methylated patients as well as a trend towards improved survival in MGMT-unmethylated patients. Our EGSS and EGOS scores successfully estimated survival in this retrospective cohort with 65% and 73% accuracy.

Conclusions

Where appropriate and safe, elderly glioblastoma patients may benefit from surgical resection and combined chemoradiotherapy with Temozolomide. The proposed EGSS and EGOS scores take into account important prognostic factors to help guide which patients should receive such treatment.

Stereotactic radiosurgery combined with immune checkpoint inhibition for the treatment of melanoma brain metastases is associated with high levels of extracranial disease control and survivorship - an abscopal effect?

Aims

Melanoma brain metastases (MBM) are a common presentation to the neuro-oncology MDT. Stereotactic radiosurgery (SRS) is a highly effective treatment for cerebral metastases, with at least 70% control rates of individual metastases,[1] whilst immune checkpoint blockade has revolutionised the management of metastatic melanoma in recent years.[2] Recent studies have demonstrated that immune checkpoint inhibition alone also has activity in the brain, with MBM response rates of 50% or more.[3, 4] When MBM are treated with combination immunotherapy and SRS together, 12-month intracranial progression free survival (PFS) rates of 85% have been achieved.[4, 5] The aim of the current study was to evaluate the local control of MBM treated at our tertiary referral centre, which benefits from specialist neuro-radiology peer review of SRS contour volumes, and further to investigate whether overall survival is also improved, and what the mechanism of this may be.

Method

A retrospective analysis of all patients treated with SRS for brain metastases at our teriary SRS centre between June 2017 – January 2020 was performed. Inclusion criteria included patients treated for MBM, who received at least 2 doses of any combination of immune checkpoint inhibition concurrently with (defined as at the time of or commenced within 3 months of) SRS. The primary endpoints were the intracranial and extracranial response rates and survival rate at 12 months. Response was defined as complete response, partial response or stable disease. Secondary endpoints included the rate of imaging-defined radionecrosis, median lesional progression free survival (mPFSlesion), non-lesional intracranial PFS (mPFSintracranial), extracranial PFS (mPFSextracranial) and overall survival (mOS), measured from the start date of SRS to the date of event or censored at the start date of data collection. Kaplan-Meier curves and survival statistics were generated using SPSS v26.

Results

33 MBM from 18 patients were identified. The median follow up was 25.8 months (minimum 12 months). Of the 18 patients: the median age was 60 (IQR 48 – 72); 17 (94%) patients were ECOG performance status 0-1; the median number of extracranial disease sites was 2 (pre-immunotherapy) and 1 (pre-SRS); the median duration of immunotherapy treatment was 17.6 (12.9 – 28.5) months, and the median number of metastases treated per patient was 2. Of the 33 metastases: 31 (94%) were supratentorial; 6 (18%) underwent prior neurosurgical resection; the median GTV volume (cc) of unresected metastases was 0.5cc (0.1 – 2.7), and 21 (64%) were treated with single fraction SRS. The median OS and PFS for all subtypes were not reached. The rates of OS, PFSlesion, PFSintracranial and PFSextracranial at 12 months were 93.9%, 87.9%, 81.8% & 75.8% respectively.

Conclusion

Our cohort of MBM patients appear to perform favourably when compared with the current literature. When compared to a recent extensive systematic review of modern management of MBM, our lesional control rate is as good as the weighted average of concurrent SRS + immunotherapy studies (87.9% vs 85.4% 12-month PFS), however we demonstrate a significantly improved 12-month OS rate (93.9% vs 52.8%) compared to the same (mOS of 15.8 – 17.4 months in other studies).[6,7] Our extra-lesional PFS is high and, compared to extracranial PFS rates from 51% at 6-months to 70.4% at 9-months in the literature,[3,4] our 75.8% control at 12 months suggests that extracranial control could drive the OS benefit. This suggests a benefit of SRS beyond the local control of MBM and questions whether patients without brain metastases may benefit from body SABR to extracranial metastases, to elicit a similar, potentially abscopal type effect.

P14.24 Estimating survival outcomes in elderly (70+ years) patients with primary glioblastoma

BACKGROUND

Elderly patients with glioblastoma are perceived to face a poor prognosis, with perceptions around older age and a relative lack of randomized data raising a concern about their undertreatment. The EANO guidelines recommend &gt;70-year-old patients with good performance status to undergo maximal safe resection followed by hypofractionated (40 Gy in 15 fractions, i.e. RT40/15) radiotherapy with or without concurrent and adjuvant Temozolomide (TMZ), depending on MGMT promoter methylation. This study evaluated the relative survival impact of biological, histological, surgical and oncological factors and aimed to devise a scoring system to estimate the survival of elderly glioblastoma patients, with an aim to more accurately guide treatment in this cohort.

METHODS

The records of 169 elderly (≥70 years) patients with a new diagnosis of IDH-wild type glioblastoma were retrospectively examined for gender, age, WHO performance status (PS), comorbidities, MGMT methylation, surgical intervention and chemoradiation regime. The adjusted survival impact of these factors was determined using Cox proportional hazards model and used to devise a two-stage scoring system to estimate survival of patients at the stage of surgical (Elderly Glioblastoma Surgical Score, EGSS) and oncological management (Elderly Glioblastoma Oncological Score, EGOS).

RESULTS

The overall median survival (MS) of the cohort was 28.8 weeks. Subtotal resection (MS=27.7 weeks, 95%CI 24.1–31.6 weeks, HR=0.58) and gross-total resection (MS=77.8 weeks, 95%CI 67.0–88.6 weeks, HR=0.36) were associated with significant overall survival benefit compared to biopsy alone (MS=18.2 weeks, 95%CI 15.7–20.7 weeks, HR=5.23), p&lt;0.05. Hypofractionated radiation with Temozolomide (RT40/15+TMZ, MS=60.9 weeks, 95%CI 49.9–71.8 weeks, HR=0.13) was non-inferior to the Stupp protocol (RT60/30+TMZ, MS=50.6 weeks, 95%CI 32.4–66.7 weeks, HR=0.11), p=0.72. Negative prognosticators included age above 75 years, biopsy alone and no chemoradiotherapy. Subgroup analysis revealed that MGMT unmethylated 70–75 year old patients who received the Stupp protocol had significantly improved overall survival (MS=57.6 weeks, 95%CI 27.7–88.1 weeks) compared to standard of care RT40/15 alone (MS=29.7 weeks, 95%CI 7.1–51.6 weeks), p=0.002. EGSS and EGOS scores estimated survival with 65% and 73% accuracy, respectively.

CONCLUSION

When appropriate and safe, a subgroup of elderly glioblastoma patients may benefit from more aggressive surgical and oncological management. The proposed EGSS and EGOS scores takes into account important prognostic factors to help guide which patients should receive such treatment.

P14.29 The treatment of melanoma brain metastases with stereotactic radiosurgery concurrently with immune checkpoint inhibition is associated with improved extracranial disease control and overall survival compared to the overall metastatic melanoma cohort - a synergistic effect reaching beyond local control?

BACKGROUND

Melanoma brain metastases (MBM) are an increasingly common referral to the neuro-oncology MDT in the context of lengthening survivorship of metastatic melanoma (MM) patients in the immunotherapy era. Stereotactic radiosurgery (SRS) and immune checkpoint inhibition (ICI) are both effective in the management of MBM and, when combined, 12-month local control rates of &gt;85% and overall survival (OS) &gt;80% have been reported.[4,5] Recent local analysis of patients treated at our tertiary SRS referral centre has revealed even greater outcomes in this patient cohort. This study aimed to compare the outcomes of patients with MBM treated with concurrent SRS and ICI compared to the overall metastatic melanoma cohort, to elucidate whether the addition of SRS to ICI may improve disease control outside of the brain as well as within.

MATERIAL AND METHODS

A retrospective analysis of our local SRS database and an ARIA ePrescribing database search was performed to identify a cohort of patients treated with concurrent SRS and ICI for MBM, as well as a control cohort of MM patients who received ICI alone, over a 4 year period until February 2020. The primary endpoints were the extracranial progression free survival (PFS) and overall survival (OS) at 12 months. Secondary endpoints were the median PFS (mPFS) and OS (mOS). Kaplan-Meier curves and survival statistics were generated using SPSS v26.

RESULTS

A total of 34 MBM from 19 patients were identified in the SRS+ICI group and there were 200 patients in the control group. The minimum follow up was 12 months. The median patient age, duration of ICI and use of combination ICI favoured the SRS+ICI group. The number of sites of extracranial disease pre-ICI and overall anti-PD-1 usage was well matched. In the SRS+ICI group, there were no cases of extracranial progression and no deaths within 12 months. In the control group, the 12-month PFS and OS rates were 50.5% and 77.5% respectively. In terms of mPFS, this was not reached (estimated 37.6 months) in the SRS+ICI group, versus 13.4 months in the control group (log rank test, p=0.001). In terms of mOS, this was not reached in the SRS+ICI group, versus 55.8 months in the control group (log rank test, p=0.016).

CONCLUSION

We demonstrate improved extracranial disease control and survivorship amongst metastatic melanoma patients who develop brain metastases and are treated with concurrent SRS and ICI compared to those who do not. The outcomes of our control cohort are comparable to the 4-year follow up of the CheckMate 067 trial (n=945),[6] which strengthens the validity of the statistical comparisons made in this study. The improved extracranial disease control seen when SRS and ICI are combined in the treatment of MBM questions whether an abscopal effect may be at play, and therefore further accents the utility of SRS in MBM beyond that of local control alone. This could influence management in cases of borderline decisions for SRS.

P14.85 Impact of the neuro-radiologist and neuro-surgeon in contouring with the neuro-oncologist on local relapse rates for brain metastases treated with stereotactic radiosurgery

BACKGROUND

The audit evaluates the value of MDT, including neuro-radiologist and neuro-surgeon, review of contouring carried out by a clinical oncologist in stereotactic radiosurgery (SRS).

MATERIAL AND METHODS

A sequential audit was conducted of all patients receiving intracranial SRS at our local institution for the first 22 months of a new SRS service. Lesions were contoured first by clinical oncologist then reviewed/edited by the MDT. The initial contour was compared with final contour using Jaccard conformity and geographical miss indices. The dosimetric impact of a contouring change was assessed using plan metrics to both original and final contour. The impact of the contouring review on local relapse, overall survival and radio necrosis rate was evaluated with at least 24 months follow up (24–46 months).

RESULTS

113 patients and 142 lesions treated over 22 months were identified. Mean JCI was 0.92 (0.32–1.00) and 38% needed significant editing (JCI&lt;0.95). Mean GMI was 0.03 (0.0–0.65) and 17% showed significant miss (GMI&gt;0.05). Resection cavities showed more changes, with lower JCI and higher GMI (p&lt;0.05). There was no significant improvement on JCI or GMI shown over time. Dosimetric analysis indicated a strong association of conformity metrics with PTV dose metrics; a 0.1 change in GTV conformity metric association with 6–17% change in dose to 95% of resulting PTV. Greater association was seen in resection cavity suggesting the geographical nature of a typical contouring error gives rise to greater potential change in dose. Clinical outcomes compared well with published series. Median survival was 20 months and local relapse free rate in the treated areas of 0.89 (0.8–0.94) at 40 months, and 0.9 (0.83–0.95) radio-necrosis free rate at 40 months with a median 17 months to developing radio-necrosis for those that did.

CONCLUSION

This work highlights that a MDT contour review adds significant value to SRS and the approach translates into reduced local recurrence rates at our local institution compared with previously published data. Radio-necrosis rates are below 10%. No improvement in clinical oncologist contouring over time was shown indicating a collaborative approach is needed regardless of experience of clinical oncologist. MDT input is recommended in particular in contouring of resection cavities.

Second-line FOLFOX chemotherapy versus active symptom control for advanced biliary tract cancer (ABC-06): a phase 3, open-label, randomised, controlled trial

BACKGROUND

Advanced biliary tract cancer has a poor prognosis. Cisplatin and gemcitabine is the standard first-line chemotherapy regimen, but no robust evidence is available for second-line chemotherapy. The aim of this study was to determine the benefit derived from second-line FOLFOX (folinic acid, fluorouracil, and oxaliplatin) chemotherapy in advanced biliary tract cancer.

METHODS

The ABC-06 clinical trial was a phase 3, open-label, randomised trial done in 20 sites with expertise in managing biliary tract cancer across the UK. Adult patients (aged ≥18 years) who had histologically or cytologically verified locally advanced or metastatic biliary tract cancer (including cholangiocarcinoma and gallbladder or ampullary carcinoma) with documented radiological disease progression to first-line cisplatin and gemcitabine chemotherapy and an Eastern Cooperative Oncology Group performance status of 0-1 were randomly assigned (1:1) centrally to active symptom control (ASC) and FOLFOX or ASC alone. FOLFOX chemotherapy was administered intravenously every 2 weeks for a maximum of 12 cycles (oxaliplatin 85 mg/m2, L-folinic acid 175 mg [or folinic acid 350 mg], fluorouracil 400 mg/m2 [bolus], and fluorouracil 2400 mg/m2 as a 46-h continuous intravenous infusion). Randomisation was done following a minimisation algorithm using platinum sensitivity, serum albumin concentration, and stage as stratification factors. The primary endpoint was overall survival, assessed in the intention-to-treat population. Safety was also assessed in the intention-to-treat population. The study is complete and the final results are reported. This trial is registered with ClinicalTrials.gov, NCT01926236, and EudraCT, 2013-001812-30.

FINDINGS

Between March 27, 2014, and Jan 4, 2018, 162 patients were enrolled and randomly assigned to ASC plus FOLFOX (n=81) or ASC alone (n=81). Median follow-up was 21·7 months (IQR 17·2-30·8). Overall survival was significantly longer in the ASC plus FOLFOX group than in the ASC alone group, with a median overall survival of 6·2 months (95% CI 5·4-7·6) in the ASC plus FOLFOX group versus 5·3 months (4·1-5·8) in the ASC alone group (adjusted hazard ratio 0·69 [95% CI 0·50-0·97]; p=0·031). The overall survival rate in the ASC alone group was 35·5% (95% CI 25·2-46·0) at 6 months and 11·4% (5·6-19·5) at 12 months, compared with 50·6% (39·3-60·9) at 6 months and 25·9% (17·0-35·8) at 12 months in the ASC plus FOLFOX group. Grade 3-5 adverse events were reported in 42 (52%) of 81 patients in the ASC alone group and 56 (69%) of 81 patients in the ASC plus FOLFOX group, including three chemotherapy-related deaths (one each due to infection, acute kidney injury, and febrile neutropenia). The most frequently reported grade 3-5 FOLFOX-related adverse events were neutropenia (ten [12%] patients), fatigue or lethargy (nine [11%] patients), and infection (eight [10%] patients).

INTERPRETATION

The addition of FOLFOX to ASC improved median overall survival in patients with advanced biliary tract cancer after progression on cisplatin and gemcitabine, with a clinically meaningful increase in 6-month and 12-month overall survival rates. To our knowledge, this trial is the first prospective, randomised study providing reliable, high-quality evidence to allow an informed discussion with patients of the potential benefits and risks from second-line FOLFOX chemotherapy in advanced biliary tract cancer. Based on these findings, FOLFOX should become standard-of-care chemotherapy in second-line treatment for advanced biliary tract cancer and the reference regimen for further clinical trials.

FUNDING

Cancer Research UK, StandUpToCancer, AMMF (The UK Cholangiocarcinoma Charity), and The Christie Charity, with additional funding from The Cholangiocarcinoma Foundation and the Conquer Cancer Foundation Young Investigator Award for translational research.

High Quality Clinical Stereotactic Radiosurgery Planning and Delivery With Standard Resolution (5 mm) Multileaf Collimation and Multiple Isocenters

PURPOSE

Our purpose was to demonstrate the use of novel planning techniques in producing high-quality stereotactic radiosurgery (SRS) plans using a standard 5 mm multileaf collimator (MLC) and multiple isocenters delivered clinically at a local institution.

METHODS AND MATERIALS

Novel planning techniques consisted of offset isocenter, variable asymmetrical jaws, and Digital Imagine and Communications in Medicine (DICOM) edits to reduce leaf tip transmission, all with the aim of maximizing dose conformity. A local institution clinical cohort was planned (1-4 targets), and plan conformity metrics common to SRS were compared against conformity metrics from selected previous publications comparing Gamma Knife to linear accelerator SRS using high-definition MLC (2.5 mm). Additionally, local institution plan conformity metrics for 2 benchmark SRS planning cases (3 and 7 targets) were compared with metrics from other centers treating SRS clinically in England. Pretreatment quality assurance results, both point dose measurement and film analysis, are presented to demonstrate plan deliverability.

RESULTS

Clinical conformity metrics are shown to be comparable to previously published results using either Gamma Knife or linear accelerator with high-definition MLC. Metrics from benchmark planning cases are shown to be comparable and to have better prescription dose conformity than average nationally in England. Pretreatment quality assurance results demonstrate suitable plan deliverability.

CONCLUSIONS

SRS planning using standard 5 mm MLC and multiple isocenters produces high-quality treatment plans for a limited number of targets with a high degree of dose conformity and dose fall off when employing novel planning techniques to compensate for MLC leaf size and multiple isocenters.

Radiolabelling and immunohistochemistry reveal platelet recruitment into lungs and platelet migration into airspaces following LPS inhalation in mice

INTRODUCTION

Platelets are under investigation for their role in host defence and inflammatory lung diseases and have been demonstrated to be recruited to the lung. However, the mechanisms and consequences of platelet recruitment into lungs are poorly understood. We have utilised a murine model to investigate the mechanisms of platelet involvement in lung inflammation induced by intranasal administration of LPS.

OBJECTIVES

Our aim was to characterise lung platelet recruitment following LPS inhalation in mice using immunohistochemistry, and non-invasive and invasive radiolabelled platelet tracking techniques.

RESULTS

Intranasal administration of LPS caused an increase in lung platelet staining in lung tissue and elicited the recruitment of radiolabelled platelets into the lung. Prior to these responses in the lung, we observed an earlier decrease in blood platelet counts, temporally associated with platelet recruitment to the liver and spleen. Non-invasive measurements of thoracic radioactivity reflected changes in blood counts rather than extravascular lung platelet recruitment. However, both in situ counting of radiolabelled platelets and immunostaining for platelet surface markers showed LPS-induced increases in extravascular platelets into lung airspaces suggesting that some of the platelets recruited to the lung enter air spaces.

CONCLUSIONS

Intranasal administration of LPS activates the innate immune response which includes a fall in peripheral blood platelet counts with subsequent platelet recruitment to the lung, spleen and liver, measured by immunohistochemistry and radiolabelling techniques.

ABC-06 | A randomised phase III, multi-centre, open-label study of active symptom control (ASC) alone or ASC with oxaliplatin / 5-FU chemotherapy (ASC+mFOLFOX) for patients (pts) with locally advanced / metastatic biliary tract cancers (ABC) previously-treated with cisplatin/gemcitabine (CisGem) chemotherapy

4003

Background: Level A evidence supports use of CisGem as first-line chemotherapy for ABC; no robust evidence is available for second-line chemotherapy. Methods: Pts diagnosed with ABC with disease progression after prior CisGem were randomised (1:1) to either ASC+mFOLFOX or ASC. Randomisation was stratified by serum albumin levels ( < 35 vs ≥35 g/L), platinum sensitivity (determined from first-line CisGem) and disease extent (locally advanced vs metastatic). Pts with ECOG PS0-1, adequate haematological, renal and liver function, and adequate biliary drainage were eligible. Primary end-point was overall survival (OS) (multivariable Cox regression adjusted for stratification factors); sample size: 162 pts delivering 148 events were required (80% power; 5% two-sided alpha) for a hypothesised hazard ratio (HR) of 0.63. Assumed median survival for ASC was 4 months. Results: 162 pts (81 in each arm) were randomised (27 March ‘14 - 04 Jan ‘18); median age 65 yrs (range 26-84); sex: 80 (49%) male, 82 (51%) female; primary site: intrahepatic 72 (44%), extrahepatic 45 (28%), gallbladder 34 (21%) and ampullary 11 (7%). Baseline characteristics were balanced between arms except platinum sensitivity (ASC+mFOLFOX 27 pts (33%); ASC 34 pts (42%)). After 150 OS events, the adjusted HR was 0.69 (95% CI 0.50-0.97; p = 0.031; ASC+mFOLFOX vs ASC). Median OS (months (m)), 6m and 12m OS-rate (%) were 6.2m, 50.6% and 25.9% for the ASC+mFOLFOX and 5.3m, 35.5%, 11.4% for the ASC arm, respectively. Grade 3/4 toxicities were reported in 48 (59%) and 32 (39%) pts in the ASC+mFOLFOX and ASC arm, respectively; these were balanced between arms except for fatigue and neutropenia (more frequent in ASC+mFOLFOX arm); data cleaning is ongoing. No chemotherapy-related deaths were reported. Conclusion: Survival with ASC was greater than assumed; ASC+mFOLFOX improved OS after progression to CisGem with a clinically meaningful increase in 6m and 12m OS rate. ASC+mFOLFOX should become standard of care in second-line for ABC. Clinical trial information: NCT01926236.

Pore-forming bioinks to enable spatio-temporally defined gene delivery in bioprinted tissues

The regeneration of complex tissues and organs remains a major clinical challenge. With a view towards bioprinting such tissues, we developed a new class of pore-forming bioink to spatially and temporally control the presentation of therapeutic genes within bioprinted tissues. By blending sacrificial and stable hydrogels, we were able to produce bioinks whose porosity increased with time following printing. When combined with amphipathic peptide-based plasmid DNA delivery, these bioinks supported enhanced non-viral gene transfer to stem cells in vitro. By modulating the porosity of these bioinks, it was possible to direct either rapid and transient (pore-forming bioinks), or slower and more sustained (solid bioinks) transfection of host or transplanted cells in vivo. To demonstrate the utility of these bioinks for the bioprinting of spatially complex tissues, they were next used to zonally position stem cells and plasmids encoding for either osteogenic (BMP2) or chondrogenic (combination of TGF-β3, BMP2 and SOX9) genes within networks of 3D printed thermoplastic fibers to produce mechanically reinforced, gene activated constructs. In vivo, these bioprinted tissues supported the development of a vascularised, bony tissue overlaid by a layer of stable cartilage. When combined with multiple-tool biofabrication strategies, these gene activated bioinks can enable the bioprinting of a wide range of spatially complex tissues.

Mesenchymal stem cell fate following non-viral gene transfection strongly depends on the choice of delivery vector

Controlling the phenotype of mesenchymal stem cells (MSCs) through the delivery of regulatory genes is a promising strategy in tissue engineering (TE). Essential to effective gene delivery is the choice of gene carrier. Non-viral delivery vectors have been extensively used in TE, however their intrinsic effects on MSC differentiation remain poorly understood. The objective of this study was to investigate the influence of three different classes of non-viral gene delivery vectors: (1) cationic polymers (polyethylenimine, PEI), (2) inorganic nanoparticles (nanohydroxyapatite, nHA) and (3) amphipathic peptides (RALA peptide) on modulating stem cell fate after reporter and therapeutic gene delivery. Despite facilitating similar reporter gene transfection efficiencies, these nanoparticle-based vectors had dramatically different effects on MSC viability, cytoskeletal morphology and differentiation. After reporter gene delivery (pGFP or pLUC), the nHA and RALA vectors supported an elongated MSC morphology, actin stress fibre formation and the development of mature focal adhesions, while cells appeared rounded and less tense following PEI transfection. These changes in MSC morphology correlated with enhanced osteogenesis following nHA and RALA transfection and adipogenesis following PEI transfection. When therapeutic genes encoding for transforming growth factor beta 3 (TGF-β3) and/or bone morphogenic protein 2 (BMP2) were delivered to MSCs, nHA promoted osteogenesis in 2D culture and the development of an endochondral phenotype in 3D culture, while RALA was less osteogenic and appeared to promote a more stable hyaline cartilage-like phenotype. In contrast, PEI failed to induce robust osteogenesis or chondrogenesis of MSCs, despite effective therapeutic protein production. Taken together, these results demonstrate that the differentiation of MSCs through the application of non-viral gene delivery strategies depends not only on the gene delivered, but also on the gene carrier itself.

STATEMENT OF SIGNIFICANCE

Nanoparticle-based non-viral gene delivery vectors have been extensively used in regenerative medicine, however their intrinsic effects on mesenchymal stem cell (MSC) differentiation remain poorly understood. This paper demonstrates that different classes of commonly used non-viral vectors are not inert and they have a strong effect on cell morphology, stress fiber formation and gene transcription in MSCs, which in turn modulates their capacity to differentiate towards osteogenic, adipogenic and chondrogenic lineages. These results also point to the need for careful and tissue-specific selection of nanoparticle-based delivery vectors to prevent undesired phenotypic changes and off-target effects when delivering therapeutic genes to damaged or diseased tissues.

Pain-like behaviour and spinal changes in the monosodium iodoacetate model of osteoarthritis in C57Bl/6 mice

BACKGROUND

Osteoarthritis (OA) is a highly prevalent, age-related pain condition that poses a significant clinical problem. Here, in the monosodium iodoacetate (MIA) model of OA, we have characterized pain behaviours and associated changes at the first pain synapse in the dorsal horn of the spinal cord.

METHODS

Mice received intra-articular injections of 0.5, 0.75 and 1 mg MIA and mechanical paw withdrawal threshold was monitored for up to 4 weeks. An intrathecal injection of peptide antagonist calcitonin gene-related peptide (CGRP8-37 ) was given 3 weeks post MIA and paw withdrawal thresholds were measured after 1 and 3 h. Immunohistochemical analysis of the lumbar dorsal horn was carried out and activity-evoked CGRP release was measured from isolated lumbar dorsal horn slices - with dorsal roots attached.

RESULTS

By 2 weeks after intra-articular MIA injection, mechanical hypersensitivity was established in the ipsilateral hindpaw. There was no evidence of sensory neuron damage in lumbar dorsal root ganglia 7 days after 1 mg MIA. However, both dorsal horn neuron activation and microglial response (Fos and Iba-1 immunostaining) but not reactive astrocytes (glial fibrillary acidic protein) were observed. Evoked CGRP release was greater from dorsal horn slices of MIA-treated mice compared with control. Furthermore, intrathecal administration of peptide antagonist CGRP8-37 acutely attenuated established MIA-induced mechanical hypersensitivity.

CONCLUSIONS

Intra-articular MIA is associated with referred mechanical hypersensitivity and increased release of CGRP from primary afferent fibres in the dorsal horn where second-order neuron activation is associated with a microglial response. Antagonism of CGRP receptor activation provides a therapeutic avenue for the treatment of pain in OA.

The population-based prevalence of achondroplasia and thanatophoric dysplasia in selected regions of the US

There have been no large population-based studies of the prevalence of achondroplasia and thanatophroic dysplasia in the United States. This study compared data from seven population-based birth defects monitoring programs in the United States. We also present data on the association between older paternal age and these birth defects, which has been described in earlier studies. The prevalence of achondroplasia ranged from 0.36 to 0.60 per 10,000 livebirths (1/27,780-1/16,670 livebirths). The prevalence of thanatophoric dysplasia ranged from 0.21 to 0.30 per 10,000 livebirths (1/33,330-1/47,620 livebirths). In Texas, fathers that were 25-29, 30-34, 35-39, and > or =40 years of age had significantly increased rates of de novo achondroplasia among their offspring compared with younger fathers. The adjusted prevalence odds ratios were 2.8 (95% CI; 1.2, 6.7), 2.8 (95% CI; 1.0, 7.6), 4.9 (95% CI; 1.7, 14.3), and 5.0 (95% CI; 1.5, 16.1), respectively. Using the same age categories, the crude prevalence odds ratios for de novo cases of thanatophoric dysplasia in Texas were 5.8 (95% CI; 1.7, 9.8), 3.9 (95% CI; 1.1, 6.7), 6.1 (95% CI; 1.6, 10.6), and 10.2 (95% CI; 2.6, 17.8), respectively. These data suggest that thanatophoric dysplasia is one-third to one-half as frequent as achondroplasia. The differences in the prevalence of these conditions across monitoring programs were consistent with random fluctuation. Birth defects monitoring programs may be a good source of ascertainment for population-based studies of achondroplasia and thanatophoric dysplasia, provided that diagnoses are confirmed by review of medical records.

Subdural haematoma and effusion in infancy: an epidemiological study

AIM

To determine incidence, aetiology, and clinical features of subdural haematoma and effusion (SDH/E) in infancy throughout the British Isles.

METHODS

Cases were notified to the British Paediatric Surveillance Unit over 12 months by paediatricians, neurosurgeons, and paediatric and forensic pathologists.

RESULTS

A total of 186 infants (121 boys, 65 girls) aged 0-2 years were identified. Annual incidence of SDH/E for the UK and Republic of Ireland is 12.54/100,000 aged 0-2 (95% CI 10.3 to 14.62) and 24.1/100,000 aged 0-1 (95% CI 20.89 to 28.18). A total of 106 infants suffered non-accidental head injury (NAHI), 7 accidental head injury, 26 a perinatal cause, 7 a non-traumatic medical condition, 23 meningitis, and in 17 the cause was undetermined; 35 infants died. Significant differences were found in injury pattern, body weight, and Townsend score between NAHI and SDH/E from other cause. There were fewer diagnostic investigations in non-NAHI cases. Delay in diagnosis of greater than a week occurred in 48/181.

CONCLUSION

SDH/E is a significant cause of morbidity and mortality in infancy. NAHI is the predominant cause of SDH/E. SDH/E can present in a non-specific and varied way and must be considered in any infant who is unwell. Determining the cause of the SDH/E in some cases continues to present a diagnostic challenge.

Bond breaking coupled with translation in rolling of covalently bound molecules

The response of a C60 molecule to manipulation across a surface displays a long range periodicity which corresponds to a rolling motion. A period of three or four lattice constants is observed and is accompanied by complex subharmonic structure due to molecular hops through a regular, repeating sequence of adsorption states. Combining experimental data and ab initio calculations, we show that this response corresponds to a rolling motion in which two of the four Si-C60 covalent bonds act as a pivot over which the molecule rotates while moving through one lattice constant and identify a sequence of C60 bonding configurations that accounts for the periodic structure.

Moving out and moving on: some ethnographic observations of deinstitutionalization in an Australian community

Since the 1950s deinstitutionalization has taken place for people with mental illnesses in the Western world. The growth of community care and residential facilities, as well as planning and implementation of policies, has varied in timing and orientation. An appreciation of the process of change affecting people discharged to the community highlights their strength, resilience, and vulnerabilities. This paper outlines a two and a half year ethnographic qualitative study undertaken in Australia, where 47 long-stay psychiatric inpatients were discharged to the community. The process accompanied the amalgamation of two major psychiatric hospitals, resulting in the closure of one. Findings demonstrated slow but positive change for residents as they reintegrated into the community. A separate quantitative and economic study was undertaken alongside the qualitative study (for results see Hobbs, et al., 2000; Newton, et al, 2000; Lapsley, et al., 2000).

Deinstitutionalisation for long-term mental illness: an ethnographic study

OBJECTIVE

Deinstitutionalisation of seriously mentally ill people in the developed world, including Australia, has occurred since the middle of this century. Evaluation of the effects of this change on the lives of individuals is of paramount importance to ensure that policies are acceptable and effective. Increasingly, multifaceted studies are considered essential for comprehensive health research. The qualitative aspect of this study complements the clinical and economic components.

METHOD

An ethnographic approach enabled contextual, qualitative data to be gathered from within the social world of 47 hospital residents as they moved to the community. A social anthropologist acting explicitly as a participant observer undertook fieldwork over two and a half years both pre- and post-discharge. Qualitative data were collected, stored and analysed separately from quantitative and economic data.

RESULTS

Ethnographic findings generally supported and, in many cases, mirrored clinical results. Of the total cohort of 47 patients transferred to the community, the 40 who continue to live outside of hospital all reported a preference for community living. The importance of freedom and simple liberties cannot be underestimated as factors that enabled this resilient group of people to work creatively through difficult periods.

CONCLUSION

Properly planned and resourced deinstitutionalisation not only maintains people with a prolonged mental illness outside of hospital, it also enhances their quality of life. Subjective descriptive material focusing on personal experiences adds meaning to quantitative research data allowing health professionals to more fully understand the implications of health policy on the lives of individuals.

Deinstitutionalisation for long-term mental illness: cost differences in hospital and community care

OBJECTIVE

This project studied the cost analysis of psychiatric hospital and then community care for long-stay patients with chronic mental illness discharged during the closure of a psychiatric hospital in Sydney.

METHOD

Expenditure and income data in both settings were collected. Costs were analysed on an occupied bed-day basis.

RESULTS

The hospital setting cost more per patient per day compared with the various community costs which were one-third to one-half of the comparable hospital costs.

CONCLUSIONS

The analysis demonstrated overall that hospital care was nearly twice as expensive as care in the community setting. The factors which may have influenced, although not necessarily altered, the substance of the findings largely related to 'organisational efficiency'. The mental hospital as an older, more rigid system was likely to be less efficient than the newer community service provision which was under intensive scrutiny both clinically and financially by all interested parties.

Deinstitutionalisation for long-term mental illness: a 2-year clinical evaluation

OBJECTIVE

The closure of a long-stay psychiatric hospital in Sydney caused the transfer of an initial 40 very long-term patients to four community residences, each with 10 beds, for a continuing process of deinstitutionalisation. Community psychiatric service support and 24-h supervision were provided. This paper describes the residents' clinical progress which was assessed over a 2-year period.

METHOD

This study employed a quasi-experimental longitudinal design. Evaluation commenced prior to discharge and continued for 2 years following community relocation using the Brief Psychiatric Rating Scale, Life Skills Profile, Social Behaviour Scale, Montgomery Asberg Depression Rating Scale and Quality Of Life measures. Readmission, demographic, case history and medication data were also collected.

RESULTS

Of the 40 patients initially transferred to the community, seven required long-term readmission to hospital (either prior to or after amalgamation) and one patient died of medical causes. Additional patients transferred from the hospital to the community following the readmissions. Three of these additional patients had achieved a 2-year community tenure during the study period and were included in the clinical evaluation. The 35 residents in total who remained in the community for 2 years, demonstrated a significant improvement in psychotic symptoms, without significant change in the level of neuroleptic medication. Importantly, the 2 years of community living resulted in a significant increase in the residents' life satisfaction. There were no statistically significant changes in residents' living skills, depressive symptoms or social behaviour problems over the 2 years, indicative of the need for supervision and community service support following deinstitutionalisation. Over the 2-year period, some 37% of the residents required temporary readmission.

CONCLUSION

This study demonstrates the clinical effectiveness of deinstitutionalisation, when planned within a mental health system with adequate community resources.

Ectopic expression of NCAM in skeletal muscle of transgenic mice results in terminal sprouting at the neuromuscular junction and altered structure but not function

The neuromuscular system provides an excellent model for the analysis of molecular interactions involved in the development and plasticity of synaptic contacts. The neural cell adhesion molecule (NCAM) is believed to be involved in the development and plasticity of the neuromuscular junction, in particular the axonal sprouting response observed in paralyzed and denervated muscle. In order to explore the role of myofiber NCAM in modulating the differentiation of motor neurons, we generated transgenic mice expressing a GPI-anchored NCAM isoform that is normally found in developing and denervated muscle, under the control of a skeletal muscle-specific promoter. This results in the constitutive expression of NCAM at postnatal ages, a time when the endogenous mouse NCAM is absent from the myofiber. We found that a significant number of neuromuscular junctions in adult transgenic animals displayed terminal sprouting (>20%) reminiscent of that elicited in response to cessation of neuromuscular activity. Additionally, a significant increase in the size and complexity of neuromuscular synapses as a result of extensive intraterminal sprouting was detected. Electrophysiological studies, however, revealed no significant alterations of neuromuscular transmission at this highly efficient synapse. Sprouting in response to paralysis or following nerve crush was also significantly enhanced in transgenic animals. These results suggest that in this ectopic expression model NCAM can directly modulate synaptic structure and motor neuron-muscle interactions. The results contrast with knockout experiments of the NCAM gene, where very limited changes in the neuromuscular system were observed.

Transgenic models of Huntington's disease

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by a CAG-polyglutamine repeat expansion. A mouse model of this disease has been generated by the introduction of exon 1 of the human HD gene carrying highly expanded CAG repeats into the mouse germ line (R6 lines). Transgenic mice develop a progressive neurological phenotype with a movement disorder and weight loss similar to that in HD. We have previously identified neuronal inclusions in the brains of these mice that have subsequently been established as the pathological hallmark of polyglutamine disease. Inclusions are present before symptoms, which in turn occur long before any selective neuronal cell death can be identified. We have extended the search for inclusions to skeletal muscle, which, like brain, contains terminally differentiated cells. We have conducted an investigation into the skeletal muscle atrophy that occurs in the R6 lines, (i) to provide possible insights into the muscle bulk loss observed in HD patients, and (ii) to conduct a parallel analysis into the consequence of inclusion formation to that being performed in brain. The identification of inclusions in skeletal muscle might be additionally useful in monitoring the ability of drugs to prevent inclusion formation in vivo.

Anterior knee pain syndrome. A review of current concepts and controversies

Anterior knee pain syndrome is a common condition in the military population. Current management is moving away from surgery as the most effective treatment, towards prolonged specific physiotherapy to recondition the extensor mechanism, especially the Vastus Medialis Obliquus (VMO) component of the quadriceps.

Formation of polyglutamine inclusions in non-CNS tissue

Huntington's disease (HD) is one of a class of inherited progressive neurodegenerative disorders that are caused by a CAG/polyglutamine repeat expansion. We have previously generated mice that are transgenic for exon 1 of the HD gene carrying highly expanded CAG repeats which develop a progressive movement disorder and weight loss with similarities to HD. Neuronal inclusions composed of the exon 1 protein and ubiquitin are present in specific brain regions prior to onset of the phenotype, which in turn occurs long before specific neurodegeneration can be detected. In this report we have extended the search for polyglutamine inclusions to non-neuronal tissues. Outside the central nervous system (CNS), inclusions were identified in a variety of post-mitotic cells. This is consistent with a concentration-dependent nucleation and aggregation model of inclusion formation and indicates that brain-specific factors are not necessary for this process. To possibly gain insights into the wasting that is observed in the human disease, we have conducted a detailed analysis of the timing and progression of inclusion formation in skeletal muscle and an investigation into the cause of the severe muscle atrophy that occurs in the mouse model. The formation of inclusions in non-CNS tissues will be particularly useful with respect to in vivo monitoring of pharmaceutical agents selected for their ability to prevent polyglutamine aggregation in vitro, without the requirement that the agent can cross the blood-brain barrier in the first instance.