Development, preclinical evaluation and preliminary dosimetry profiling of SB03178, a first-of-its-kind benzo[h]quinoline-based fibroblast activation protein-α-targeted radiotheranostic for cancer imaging and therapy

Fibroblast activation protein-α (FAP) is a marker of cancer-associated fibroblasts (CAFs) that constitute a significant portion of most carcinomas. Since it plays a critical role in tumor growth and metastasis, its timely detection to identify tumor lesions in early developmental stages using targeted radiopharmaceuticals has gained significant impetus. In the present work, two novel FAP-targeted precursors SB03178 and SB04033 comprising of an atypical benzo[h]quinoline construct were synthesized and either chelated to diagnostic radionuclide gallium-68 or therapeutic radionuclide lutetium-177, with ≥90% radiochemical purities and 22-76% decay-corrected radiochemical yields. natGa-labeled complexes displayed dose-dependent FAP inhibition, with binding potency of natGa-SB03178 being ∼17 times higher than natGa-SB04033. To evaluate their pharmacokinetic profiles, PET imaging and ex vivo biodistribution analyses were executed in FAP-overexpressing HEK293T:hFAP tumor-bearing mice. While both tracers displayed clear tumor visualization that was primarily FAP-arbitrated, with negligible uptake in most peripheral tissues, [68Ga]Ga-SB03178 demonstrated higher tumor uptake and superior tumor-to-background contrast ratios than [68Ga]Ga-SB04033. 177Lu-labeled SB03178 was subjected to tumor retention studies, mouse dosimetry profiling and mouse-to-human dose extrapolations also using the HEK293T:hFAP tumor model. [177Lu]Lu-SB03178 exhibited a combination of high and sustained tumor uptake, with excellent tumor-to-critical organ uptake ratios resulting in a high radiation absorbed dose to the tumor and a low estimated whole-body dose to humans. Our preliminary findings are considerably encouraging to support clinical development of [68Ga]Ga-/[177Lu]Lu-SB03178 theranostic pair for use in a vast majority of FAP-overexpressing neoplasms, particularly carcinomas.

341 Is CT Imaging Mandated for Confirming the Diagnosis of Acute Appendicitis in Patients Over the Age of 40?

Aim

Acute appendicitis remains a largely clinical diagnosis, with clinical scoring systems such as the Alvarado score calculated to give a quantitative assessment of the diagnostic probability. It remains common practice amongst surgeons to rely on CT scanning to confirm the diagnosis however, especially in older patients. Our aim was to assess the diagnostic performance of CT scanning compared with that of the Alvarado score in patients aged over 40 years old.

Method

We conducted a retrospective observational study of 149 patients greater than 40 years old who had a diagnosis of acute appendicitis and had undergone an appendicectomy with subsequent histological analysis. Data was extracted from patients’ electronic medical records. This was recorded in Microsoft Excel and analysed using NCSS.

Results

When using an Alvarado score cut-off point of ≥7, the sensitivity and specificity were 44.1% and 60.0% respectively. The sensitivity of the test improved to 80.3% when using a cut-off point of ≥ 5, however the specificity decreased to 50%. The accuracy improved to 78.1% from 45.3%, when using ≥ 5 as a cut-off point. On the other hand, the sensitivity of the CT scan was 84.9% and the specificity was 45.5%. The accuracy of CT scanning was 81.8%.

Conclusions

When comparing performance, pre-operative CT scanning did not show a statistically significant improvement in the diagnosis of acute appendicitis relative to Alvarado score. We recommend using an Alvarado score cut-off point of ≥ 5 to aid in diagnosing appendicitis in patients older than 40, as it accounts for a higher sensitivity.

809 USE OF NEW MOBILITY SCORE AND A TRANS-DISCIPLINARY APPROACH TO REDUCE HOSPITAL LOS, RETURN TO ORIGINAL RESIDENCE, AND MORTALITY

Introduction

The National Hip Fracture Database indicated Guy’s and St Thomas’ Trust ranked in the fourth quartile nationally with reference to hospital length of stay (LOS), return to original residence (ROR), and mortality in hip fracture patients in 2018. This quality improvement project aimed to improve and maintain these key factors via a two-stage process.

Methods

Stage one involved implementation of four key interventions through a trans-disciplinary focus group, comprising ortho-geriatricians, orthopaedic surgeons, physiotherapists (PT), occupational therapists (OT), nursing staff, and a transfer of care navigator (TCN). Firstly, the New Mobility Score (NMS) was employed as a tool to guide estimated length of stay. Secondly, use of preoperative OT assessment allowed early evaluation of patient expectations concerning discharge planning. Third, facilitation of the discharge process was optimised by the recruitment of a TCN. Lastly, attendance of a senior orthogeriatrician during the daily board round was established. Stage two involved education of new members of the trans-disciplinary team to ensure that the key interventions listed above were maintained on hip fracture patients.

Results

Following stage one, average acute hospital LOS and overall LOS decreased from 20.1 to 15.1 days and 22.4 to 18.3 days, respectively. Rate of ROR within 120 days of discharge improved from 72.4% to 86.9%, while mortality rates fell from 7.1 to 3.4. Following stage two, overall LOS improved to 17.1 days, while acute LOS and mortality were maintained at 15.6 and 3.9 days, respectively. While ROR fell to 82.8%, this remained higher than the national average at 69.9%.

Conclusions

Utilisation of NMS and multi-disciplinary input effectively improved ROR, while reducing length of hospital stay and mortality rates in hip fracture patients. Education of new members of the trans-disciplinary team allowed sustained improvement despite challenges faced during the COVID-19 pandemic.

480 Successful anticoagulation treatment of an ascending aortic thrombus associated with myocardial infarction and systemic embolism

Background

The ascending aorta is an uncommon site for non-infective mural thrombus. The detection of such a thrombus is of particular importance, given the risk of systemic and coronary embolisation. We present a case of a 60-year-old female with an ascending aortic thrombus complicated by non-ST-elevation myocardial infarction (NSTEMI), and associated systemic embolism in the form of renal and splenic infarcts.

Case Report

A 60-year-old female was admitted to a local secondary hospital with a 4-day history of crampy abdominal pain and intermittent bilateral arm pain associated with nausea and vomiting. Past medical history included known hypertrophic cardiomyopathy, gastroesophageal reflux disease, carpal tunnel syndrome, hepatic steatosis, but no known thrombophilia or coronary artery disease. Computer tomography (CT) scan of the abdomen revealed subacute infarction of the right kidney and spleen in keeping with a thrombo-embolic event. A CT pulmonary angiogram revealed a small pulmonary embolus in the right lower lobe. Troponin I level was elevated at 11 mg/L (normal <0.04 mg/L). She was treated with aspirin, clopidogrel and therapeutic enoxaparin for a NSTEMI, and transferred to a metropolitan tertiary centre for ongoing investigation. A transthoracic echocardiogram performed showed known hypertrophic cardiomyopathy, but negative for intracardiac shunting via bubble study. Coronary angiography revealed an acutely occluded distal left anterior descending (LAD) artery with no collaterals, and mild irregularities in all other coronary arteries. A transoesophageal echocardiogram performed to exclude any intracardiac sources of emboli showed a pedunculated and mobile non-calcific mass measuring 1.0cm X 0.5cm in the posterior aspect of the ascending aorta, associated with atheroma in the aortic arch. A laboratory workup for antiphospholipid syndrome, antithrombin III, protein S and protein C deficiency were negative.

After discussion with the multidisciplinary Heart team, the consensus was that the aortic mass was likely thrombus formation relating to erosion of aortic atheroma. It was hypothesised that this may have resulted in distal embolisation to the left kidney and spleen, and possibly also caused embolisation to the LAD artery, although the cause of the pulmonary embolism was still unknown. The patient was then discharged on rivaroxaban and aspirin.

A repeat transoesophageal echocardiogram was performed 4 months after discharge to assess the ascending aortic mass. It showed complete resolution of the mass in the ascending aorta, with no change in any other cardiac structures.

Discussion

Although thrombus formation is uncommon in the ascending aorta, certain conditions, such as pregnancy and thrombophilia increase its risk. Several case reports of ascending aortic thrombus were found in the literature, but this will be the first to report complete resolution with treatment using a direct oral anticoagulant.

Abstract 480 Figure. Ascending Aortic Thrombus + Resolution

Population genomic analyses of the chocolate tree, Theobroma cacao L., provide insights into its domestication process

Domestication has had a strong impact on the development of modern societies. We sequenced 200 genomes of the chocolate plant Theobroma cacao L. to show for the first time to our knowledge that a single population, the Criollo population, underwent strong domestication ~3600 years ago (95% CI: 2481-13,806 years ago). We also show that during the process of domestication, there was strong selection for genes involved in the metabolism of the colored protectants anthocyanins and the stimulant theobromine, as well as disease resistance genes. Our analyses show that domesticated populations of T. cacao (Criollo) maintain a higher proportion of high-frequency deleterious mutations. We also show for the first time the negative consequences of the increased accumulation of deleterious mutations during domestication on the fitness of individuals (significant reduction in kilograms of beans per hectare per year as Criollo ancestry increases, as estimated from a GLM, P = 0.000425).

Gene therapy in rare diseases: the benefits and challenges of developing a patient-centric registry for Strimvelis in ADA-SCID

Background

Strimvelis (autologous CD34+ cells transduced to express adenosine deaminase [ADA]) is the first ex vivo stem cell gene therapy approved by the European Medicines Agency (EMA), indicated as a single treatment for patients with ADA-severe combined immunodeficiency (ADA-SCID) who lack a suitable matched related bone marrow donor. Existing primary immunodeficiency registries are tailored to transplantation outcomes and do not capture the breadth of safety and efficacy endpoints required by the EMA for the long-term monitoring of gene therapies. Furthermore, for extended monitoring of Strimvelis, the young age of children treated, small patient numbers, and broad geographic distribution of patients all increase the risk of loss to follow-up before sufficient data have been collected. Establishing individual investigator sites would be impractical and uneconomical owing to the small number of patients from each location receiving Strimvelis.

Results

An observational registry has been established to monitor the safety and effectiveness of Strimvelis in up to 50 patients over a minimum of 15 years. To address the potential challenges highlighted above, data will be collected by a single investigator site at Ospedale San Raffaele (OSR), Milan, Italy, and entered into the registry via a central electronic platform. Patients/families and the patient’s local physician will also be able to submit healthcare information directly to the registry using a uniquely designed electronic platform. Data entry will be monitored by a Gene Therapy Registry Centre (funded by GlaxoSmithKline) who will ensure that necessary information is collected and flows between OSR, the patient/family and the patient’s local healthcare provider.

Conclusion

The Strimvelis registry sets a precedent for the safety monitoring of future gene therapies. A unique, patient-focused design has been implemented to address the challenges of long-term follow-up of patients treated with gene therapy for a rare disease. Strategies to ensure data completeness and patient retention in the registry will help fulfil pharmacovigilance requirements. Collaboration with partners is being sought to expand from a treatment registry into a disease registry. Using practical and cost-efficient approaches, the Strimvelis registry is hoped to encourage further innovation in registry design within orphan drug development.

A Comparison of Ketoprofen and Diclofenac for Acute Musculoskeletal Pain Relief: a Prospective Randomised Clinical Trial

Objectives

To compare the efficacy and adverse effects of Ketoprofen and Diclofenac in the treatment of acute musculoskeletal pain.

Methods

In a prospective randomised clinical trial, patients admitted to an emergency department with acute musculoskeletal injuries requiring intramuscular (IM) injection for pain treatment were enrolled. The target study patients were Chinese adults who suffered from any musculoskeletal injuries of less than 12 hours. They received either 100 mg of Ketoprofen or 75 mg of Diclofenac. Pain was assessed by a 10-point visual analog score (VAS) and evaluations were performed at 30-minute intervals from treatment. Rescue analgesic was given if insufficient analgesia was achieved by one hour. The outcomes and the adverse effects were recorded.

Results

We recruited 77 cases in the Diclofenac group and 74 cases in the Ketoprofen group. The demographic data with regards to age, sex and patterns of injury were comparable in both groups. Following the administration of treatment, both groups showed highly statistically significant (P<0.001) reduction in pain level at 30-minute and 60-minute intervals. Comparing the mean decrease of pain level, there was no statistically significant difference between the two groups at 30-minute interval (P=0.6) and 60-minute interval (P=0.5). In each group, there was one patient experiencing skin rash after treatment. Four patients in the Ketoprofen group and one in Diclofenac group required rescue medicine. With respect to the number of admission following treatment, there was no statistically significant difference between the two groups.

Conclusions

Ketoprofen and Diclofenac are equally effective and safe in the treatment of acute musculoskeletal pain in Hong Kong Chinese population.

A Study of Orotracheal Intubation in Emergency Departments of Five District Hospitals in Hong Kong

Objective

To study the success rates and complications of orotracheal intubation in emergency departments of five district hospitals in Hong Kong in order to identify ways for improvement.

Method

This was a prospective observational study. The emergency department doctors performing the intubation were asked to complete an intubation study form immediately after the procedure over a period of four months. Data collected included vital signs, experiences of intubators, method of intubation and complications.

Results

A total of 347 cases were collected and 93% of them were non-trauma cases. Fifty-two percent (52%) of the cases were in cardiac arrest before intubation. Rapid sequence intubation (RSI) was applied in 36% of the cases. Junior doctors first intubated about 72% of the patients. Successful intubation was achieved in 1 and 2 attempts in 70% and 89% of the cases respectively. In 10 cases (3%), secondary methods such as laryngeal mask airway, Combitube, Trachlight or cricothyroidotomy were needed. The overall complication rate was 7.8% and the complication rate in the RSI group was 15.3%. The complication rate was even higher (20%) if intubation without medication was used in non-cardiac arrest patients. Significant drop in blood pressure was the most common complication and it could be attributed to the use of midazolam as induction medication. The success rate was found to correlate with the experience of the first intubator (p<0.05) and the laryngeal view (p<0.001). The complication rate increased with repeated attempts (p<0.001) and was higher among junior doctors (p<0.05). Early use of elastic gum bougie was associated with lower complication and higher success rates.

Conclusion

Orotracheal intubation in the emergency department was associated with high complication rate. Many complications came from junior intubators. Hypotension was the most common complication. Potentially avoidable complications may be a result of failure to use RSI in non-cardiac arrest patients and failure to use bougie in cases of poor laryngeal view.

Two Pregnant Women Presenting with Umbilical Cord Prolapse

Cord prolapse is an obstetric emergency as delay in management is associated with significantly increased neonatal morbidity and mortality. If the accident occurred outside the hospital, many babies would be dead or severely asphyxiated upon arrival in the hospital. The role of Accident & Emergency (A&E) department is to arrive at this diagnosis promptly and deliver appropriate intervention. Immediate cesarean delivery is the treatment of choice. The clinical presentations of two cases with umbilical cord prolapse presenting to our A&E department within two weeks were described. The pathophysiology, risk factors, diagnosis, management as well as outcome were discussed.

A Review on the Management of Acute Gastroenteritis in Children

Acute gastroenteritis represents a frequent cause of morbidity among children in Hong Kong. Despite the large number of potential etiologic agents, principles of management of gastroenteritis are uniform and aim to prevent the two major complications - dehydration and malnutrition. A review of the literature was performed. Selected articles were appraised, graded, and synthesised qualitatively. Statements on recommendations were generated. Current evidence emphasises the use of oral rehydration and the early reintroduction of age-appropriate foods. Apart from these two, important aspects of management reviewed included laboratory investigations, role of anti-diarrhoeal agents, and use of antimicrobial agents. Criteria for admission of high-risk children are also addressed.

The impact of CT head scans on ED management and length of stay in bizarre behavior patients

METHODS

A 5-year retrospective chart review was conducted at 3 EDs. Inclusion criteria were patients ≥18years old triaged as "mental health - bizarre behavior" (deviation from normal cognitive behaviour with no obvious cause) with a CT head scan ordered in the ED. Exclusion criteria were focal neurologic deficits on exam, alternative medical etiology (i.e. delirium, trauma) and/or pre-existing CNS disease. Clinical, demographic and administrative data were extracted with 10% of charts independently reviewed by an Emergency Physician for inter-rater reliability.

RESULTS

266 cases met study criteria. Population demographics: 49% percent female, average age 51years old, 28% homeless, 58% arrived by police or ambulance. CT head results: 1 (0.4%) case with possible acute findings, 105 (39%) with incidental findings (i.e. cerebral atrophy) that did not impact clinical management. Average time to physician assessment was 1:48 (hour:min) (sd 1:11), time to CT completion was 5:05 (sd 7:28) and an average delay of 3:17 awaiting results. Subgroup analysis revealed a net increase in ED length of stay (ED LOS) of 5:02 from obtaining neuroimaging. 85% of patients were referred to a consultant, 92% were to psychiatry.

CONCLUSIONS

CT head results prolonged ED LOS, delayed patient disposition and did not change the patient's clinical management. A prospective trial for ordering CT head scans in these patients is warranted.

Long-term, high-level hepatic secretion of acid α-glucosidase for Pompe disease achieved in non-human primates using helper-dependent adenovirus

Pompe disease (glycogen storage disease type II (GSD-II)) is a myopathy caused by a genetic deficiency of acid α-glucosidase (GAA) leading to lysosomal glycogen accumulation causing muscle weakness, respiratory insufficiency and death. We previously demonstrated in GSD-II mice that a single injection of a helper-dependent adenovirus (HD-Ad) expressing GAA resulted in at least 300 days of liver secretion of GAA, correction of the glycogen storage in cardiac and skeletal muscles and improved muscle strength. Recent reports suggest that gene therapy modeling for lysososomal storage diseases in mice fails to predict outcomes in larger animal models. We therefore evaluated an HD-Ad expressing GAA in non-human primates. The baboons not only tolerated the procedure well, but the results also confirmed that a single dose of the HD-Ad allowed the livers of the treated animals to express and secrete large amounts of GAA for at least 6 months, at levels similar to those achieved in mice. Moreover, we detected liver-derived GAA in the heart, diaphragm and skeletal muscles of the treated animals for the duration of the study at levels that corrected glycogen accumulation in mice. This work validates our proof-of-concept studies in mice, and justifies future efforts using Ad-based vectors in Pompe disease patients.

A cautionary tale; squamous cell carcinoma of the gingiva

BACKGROUND AND OBJECTIVES

Oral squamous cell carcinoma is characterised by varied clinical manifestations and is often diagnosed at an advanced stage. This article highlights a case of gingival squamous cell carcinoma which was initially diagnosed and treated as localised periodontitis.

METHODS

A 64-year-old Caucasian male had a 2-year history of discomfort and swelling around his upper anterior teeth. His dentist diagnosed localised periodontitis around tooth 11. The patient was treated with regular scaling but showed no improvement. Teeth 11 and 21 were subsequently extracted. He returned later with a swelling in his anterior maxilla and was referred to the Whangarei Hospital Dental Department.

RESULTS

The histopathological report confirmed a diagnosis of squamous cell carcinoma. The patient was referred to Auckland for treatment and underwent a tracheostomy, maxillectomy, bilateral selective neck dissection and fibula free flap reconstruction. All lymph nodes retrieved and margins of the lesion were clear, and the patient did not require radiotherapy. He will be monitored over the next 5 years for recurrence.

CONCLUSIONS

Gingival squamous cell carcinoma can be easily misdiagnosed. Suspicious lesions which are non-responsive to conventional therapy should be biopsied, even if they are not in the classic high risk anatomical areas of the oral cavity.

Abstract B2-54: Intratumor heterogeneity in never-smoker Asian EGFR mutant lung adenocarcinoma

Lung cancer has the highest cancer associated mortality rate in many countries across the world. In contrast to western populations, approximately half of lung adenocarcinoma cases in Singapore harbour activating epidermal growth factor receptor (EGFR) mutations, with preponderance for never smokers and female gender. Although EGFR tyrosine kinase inhibitors (TKIs) confer high response rates of up to 70%, drug resistance invariably ensues - most commonly through the “acquisition” of EGFR T790M mutation. While the extent and pattern of intratumoral heterogeneity (ITH) in non-small cell lung cancer (NSCLC) were recently described, these studies examined histologically and molecularly diverse cohort of patients, majority being current or ex-smokers. Here we report ITH in eight never-smoker EGFR mutant lung adenocarcinoma cases of Asian ethnicity.

All eight patients had no prior treatment history and harboured an activating EGFR mutation (5 L858R , 2 exon 19 deletion, 1 exon 20 insertion). They underwent lobectomy for Stage IA, IB NSCLC. Tumors were harvested using a systematic sectoring protocol according to standard operation procedures, with tissue banked for exome sequencing, RNA-sequencing and SNP array. A total of 46 tumor sectors (at least 4 regions from each of the 8 tumors) were subject to whole exome sequencing, with matched normal samples.

With an average sequencing depth of 100x, we identified 860 somatic exonic SNVs (601 being non-synonymous) and 49 indels across all samples. The median number of SNVs per patient was 112 and per sector was 49. Notably, activating EGFR mutations were identified across all tumor sectors of all but two patients (for whom it was identified in 3 of 5 and 5 of 7 sectors respectively). In addition, we did not identify the EGFR T790M mutation in any of the sequenced tumor sectors, suggesting that, this resistance mutation is not present at detectable frequencies even as a branch or subclonal event in a treatment naïve scenario. Of 20 genes that were significantly mutated across 46 individual tumor sectors, only two overlapped with published recurrently mutated genes in NSCLC.

In conclusion, we show that activating EGFR mutations are ubiquitous truncal events in 6 of 8 Asian never-smoker lung adenocarcinoma – consistent with its role as a therapeutically tractable driver gene. The T790M mutation commonly associated with TKI resistance was not detected as a subclonal event in treatment naïve patients. Further, our study reveals the unique mutation spectra of Asian EGFR mutant lung adenocarcinoma, highlighting the value of multi-region sequencing in characterising the genomic architecture of defined molecular subsets of NSCLC from different ethnic backgrounds.

Citation Format: Rahul Nahar, Weiwei Zhai, Angela Takano, Alexis Jiaying Khng, Xingliang Liu, Chong Hee Lim, Audrey S.M. Teo, Cheryl Xueli Chan, Apoorva Gogna, Kiat-Hon Lim, Tina Koh, Huay Mei Poh, Yin Yeng Lee, Liang He Chen, Tong Zhang, Vidhya Gomathi Krishnan, N Gopalakrishna Iyer, Pauline Ng, Wan Teck Lim, Bing Lim, Eng-Huat Tan, Daniel S.W. Tan, Axel M. Hillmer. Intratumor heterogeneity in never-smoker Asian EGFR mutant lung adenocarcinoma. [abstract]. In: Proceedings of the AACR Special Conference on Computational and Systems Biology of Cancer; Feb 8-11 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 2):Abstract nr B2-54.

Abstract A1-25: Intratumor heterogeneity in never-smoker Asian EGFR mutant lung adenocarcinoma

Lung cancer has the highest cancer associated mortality rate in many countries across the world. In contrast to western populations, approximately half of lung adenocarcinoma cases in Singapore harbour activating epidermal growth factor receptor (EGFR) mutations, with preponderance for never smokers and female gender. Although EGFR tyrosine kinase inhibitors (TKIs) confer high response rates of up to 70%, drug resistance invariably ensues - most commonly through the “acquisition” of EGFR T790M mutation. While the extent and pattern of intratumoral heterogeneity (ITH) in non-small cell lung cancer (NSCLC) were recently described, these studies examined histologically and molecularly diverse cohort of patients, majority being current or ex-smokers. Here we report ITH in eight never-smoker EGFR mutant lung adenocarcinoma cases of Asian ethnicity.

All eight patients had no prior treatment history and harboured an activating EGFR mutation (5 L858R, 2 exon 19 deletion, 1 exon 20 insertion). They underwent lobectomy for Stage IA, IB NSCLC. Tumors were harvested using a systematic sectoring protocol according to standard operation procedures, with tissue banked for exome sequencing, RNA-sequencing and SNP array. A total of 46 tumor sectors (at least 4 regions from each of the 8 tumors) were subject to whole exome sequencing, with matched normal samples.

With an average sequencing depth of 100x, we identified 860 somatic exonic SNVs (601 being non-synonymous) and 49 indels across all samples. The median number of SNVs per patient was 112 and per sector was 49. Notably, activating EGFR mutations were identified across all tumor sectors of all but two patients (for whom it was identified in 3 of 5 and 5 of 7 sectors respectively). In addition, we did not identify the EGFR T790M mutation in any of the sequenced tumor sectors, suggesting that, this resistance mutation is not present at detectable frequencies even as a branch or subclonal event in a treatment naïve scenario. Of 20 genes that were significantly mutated across 46 individual tumor sectors, only two overlapped with published recurrently mutated genes in NSCLC.

In conclusion, we show that activating EGFR mutations are ubiquitous truncal events in 6 of 8 Asian never-smoker lung adenocarcinoma – consistent with its role as a therapeutically tractable driver gene. The T790M mutation commonly associated with TKI resistance was not detected as a subclonal event in treatment naïve patients. Further, our study reveals the unique mutation spectra of Asian EGFR mutant lung adenocarcinoma, highlighting the value of multi-region sequencing in characterising the genomic architecture of defined molecular subsets of NSCLC from different ethnic backgrounds.

Citation Format: Rahul Nahar, Weiwei Zhai, Angela Takano, Alexis Jiaying Khng, Xingliang Liu, Chong Hee Lim, Audrey S.M. Teo, Cheryl Xueli Chan, Apoorva Gogna, Kiat-Hon Lim, Tina Koh, Huay Mei Poh, Yin Yeng Lee, Liang He Chen, Tong Zhang, Vidhya Gomathi Krishnan, N Gopalakrishna Iyer, Pauline Ng, Wan Teck Lim, Bing Lim, Eng-Huat Tan, Daniel S.W. Tan, Axel M. Hillmer. Intratumor heterogeneity in never-smoker Asian EGFR mutant lung adenocarcinoma. [abstract]. In: Proceedings of the AACR Special Conference on Translation of the Cancer Genome; Feb 7-9, 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 1):Abstract nr A1-25.

Functional recovery of consumers discharged from mental hospital and participating in a community-based psychosocial programme provided by a non-governmental organisation

OBJECTIVE

To explore the 1-year functional recovery rate and identify factors predicting functional recovery of consumers in the Hong Kong context.

METHODS

By adopting a prospective longitudinal follow-up research design, a cohort of Chinese people discharged from the mental hospital and participating in a community-based psychosocial programme provided by a non-governmental organisation were followed up for 1 year. These individuals were assessed on their social functioning, psychiatric symptoms, self-efficacy, and quality of life using standardised assessment scales at baseline, 6 months, and 12 months of follow-up.

RESULTS

Of 87 participants, about one quarter (23.0%, n = 20) achieved functional recovery and about three quarters (79.3%, n = 69) achieved symptom remission at 12 months of follow-up. Also, the group showing functional recovery achieved better quality of life than those not showing recovery. Logistic regression analysis indicated that current functioning, current psychiatric symptoms, and achieving open employment at 12 months were significant predictors of functional recovery. These 3 predicting factors altogether accounted for half (54.4%) of the variance of functional recovery.

CONCLUSIONS

It is more difficult to achieve functional recovery than symptom remission for consumers. Helping consumers to improve social skills, achieve open employment, and reduce psychiatric symptoms is recommended as important elements in facilitating functional recovery in the local context.

Retinal transduction profiles by high-capacity viral vectors

Retinal gene therapy with adeno-associated viral (AAV) vectors is safe and effective in humans. However, the limited cargo capacity of AAV prevents their use for therapy of those inherited retinopathies (IRs) due to mutations in large (>5kb) genes. Viral vectors derived from Adenovirus (Ad), Lentivirus (LV) and Herpesvirus (HV) can package large DNA sequences but do not target efficiently retinal photoreceptors (PRs) where the majority of genes responsible for IRs are expressed.

Here, we have evaluated the mouse retinal transduction profiles of vectors derived from 16 different Ad serotypes, 7 LV pseudotypes, and from a bovine HV. Most of the vectors tested transduced efficiently the retinal pigment epithelium (RPE). We found that LV-GP64 tends to transduce more PRs than the canonical LV-VSVG albeit this was restricted to a narrow region. We observed more extensive PR transduction with HdAd1, 2 and 5/F35++ than with LV, although none of them outperformed the canonical HdAd5 or matched the extension of PR transduction achieved with AAV2/8.

Quality of life in people with mental illness in non-residential community mental health services in Hong Kong

OBJECTIVE

To identify the subjective quality of life in people with chronic mental health problems who were in non-residential community mental health services, and to investigate factors affecting their quality of life after the illness.

METHODS

People with mental illness (n = 105) were recruited. They were assessed with the self-rated Hong Kong Chinese version of the World Health Organization Quality of Life Brief questionnaire.

RESULTS

The participants had lower total quality-of-life and the 4 domain scores of the questionnaire than the general population. They were particularly dissatisfied with their financial situation. Duration of illness was positively correlated with subjective quality-of-life variables while age at onset of the mental illness was negatively correlated with subjective quality of life, in particular the physical health, psychological health, and environmental domains.

CONCLUSION

This study highlighted the significance of duration and age at onset of illness in subjective quality of life of people with mental illness. A longitudinal study to test the causal relationships between these factors and the quality of life in people with mental illness is recommended.

Cognitive control of attention is differentially affected in trauma-exposed individuals with and without post-traumatic stress disorder

BACKGROUND

This study aimed to determine whether patients with post-traumatic stress disorder (PTSD) show difficulty in recruitment of the regions of the frontal and parietal cortex implicated in top-down attentional control in the presence and absence of emotional distracters.

METHOD

Unmedicated individuals with PTSD (n = 14), and age-, IQ- and gender-matched individuals exposed to trauma (n = 15) and healthy controls (n = 19) were tested on the affective number Stroop task. In addition, blood oxygen level-dependent responses, as measured via functional magnetic resonance imaging, were recorded.

RESULTS

Patients with PTSD showed disrupted recruitment of lateral regions of the superior and inferior frontal cortex as well as the parietal cortex in the presence of negative distracters. Trauma-comparison individuals showed indications of a heightened ability to recruit fronto-parietal regions implicated in top-down attentional control across distracter conditions.

CONCLUSIONS

These results are consistent with suggestions that emotional responsiveness can interfere with the recruitment of regions implicated in top-down attentional control; the heightened emotional responding of patients with PTSD may lead to the heightened interference in the recruitment of these regions.

A second peritoneal cytology instead of the initial cytology as a prognostic factor in epithelial ovarian cancer

e16572

Background: Ovarian cancer (OvCa) is the most common gynecological malignancy causing death. Positive (+ve) peritoneal cytology is an important prognostic factor. The role of a repeat peritoneal washing after resection of the tumor at the time of surgery has not been evaluated in the past. Methods: A retrospective analysis of our prospective cohort database was undertaken. Patients (pts) diagnosed with OvCa between 2001–2007 were included in the study. All pts underwent debulking surgery with two peritoneal washings during surgery: one before and one after resection of the tumor. The primary outcome was overall survival. Exclusion criteria included second malignancy, refusal of chemotherapy, or non-surgical candidates. Only stage III andIV pts were included in the follow-up analysis. Results: Forty three pts were included in our study. Of these, 8 (gp A) had both peritoneal washings +ve for malignancy, 16 (gp B) had the first washing +ve and the second one negative (-ve) for malignancy, and 19 (gp C) had both washings -ve for malignancy. There was no significant difference in the demographics and grade of disease (Table). There was more serous histology in gp B as compared to gp A and gp C. The median length of stay was 13.2, 10.9, 9 days and the median CA 125 level at the time of diagnosis was 651, 440 and 445 in gp A, B and C respectively. Bowel was involved and required radical resection in 75%, 41.7%, and 26.3% in gp A, B, and C, however the rates of optimal cytoreduction were 75%, 84.6% and 90.9% respectively. The minimum follow-up was 12 months. The percentage of pts with persistent or recurrent disease was 62.5%, 41.7%, and 36.4% in gpA, B and C respectively. There was improved survival in gp C as compared to gp B and gp A. (42 months vs 23.5 months vs 13 months respectively). Conclusions: While preliminary, our study shows that at the time of debulking surgery of OvCa, a -ve peritoneal washing after resection of the tumor following an initial +ve washing is a possible independent prognostic factor. [Table: see text]

No significant financial relationships to disclose.

Adult Morgagni hernia: the need for clinical awareness, early diagnosis and prompt surgical intervention

We report an unusual case of strangulated diaphragmatic (Morgagni) hernia resulting in ischaemia of the small and large bowel, which was initially diagnosed as a pneumonia. This case highlights the importance of being aware of this rare, but potentially fatal condition when assessing patients with respiratory symptoms and abdominal pain.

Accurate classification of MLH1/MSH2 missense variants with multivariate analysis of protein polymorphisms-mismatch repair (MAPP-MMR)

Lynch syndrome, also known as hereditary nonpolyposis colon cancer (HNPCC), is the most common known genetic syndrome for colorectal cancer (CRC). MLH1/MSH2 mutations underlie approximately 90% of Lynch syndrome families. A total of 24% of these mutations are missense. Interpreting missense variation is extremely challenging. We have therefore developed multivariate analysis of protein polymorphisms-mismatch repair (MAPP-MMR), a bioinformatic algorithm that effectively classifies MLH1/MSH2 deleterious and neutral missense variants. We compiled a large database (n>300) of MLH1/MSH2 missense variants with associated clinical and molecular characteristics. We divided this database into nonoverlapping training and validation sets and tested MAPP-MMR. MAPP-MMR significantly outperformed other missense variant classification algorithms (sensitivity, 94%; specificity, 96%; positive predictive value [PPV] 98%; negative predictive value [NPV], 89%), such as SIFT and PolyPhen. MAPP-MMR is an effective bioinformatic tool for missense variant interpretation that accurately distinguishes MLH1/MSH2 deleterious variants from neutral variants.

Ultrastaging of sentinel lymph nodes (SLNs) compared to non-SLNs in colorectal (CRca) cancer: Do we need both?

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Background: SLN mapping (M) accurately stages many solid tumors including CRca. SLNs are 3–5 times more likely to have metastases (mets) when ultrastaged by microsections and IHC as compared to non-SLNs examined by standard pathological methods. It is unknown whether ultrastaging of initially -ve non-SLNs would lead to higher incidence of +ve nodes. Hence, we retrospectively analyzed all initially -ve non-SLNs by microsections and IHC similar to SLNs in CRca patients (pts) undergoing SLNM to determine its impact on final nodal staging. Methods: All CRca pts underwent SLNM by circumferential subserosal injection of 1% lymphazurin. First 1–4 blue nodes were marked as SLNs and ultrastaged by 4 section with H&E and 1 with IHC. All non-SLNs were initially examined by single H& E section and initial staging was made as per AJCC criteria. We re-examined all initially -ve non-SLNs similar to the SLNs by a senior pathologist blinded to prior results. Results: There were 156 pts with Cca and 44 pts with Rca. SLNM was successful in 100% pts with 94% accuracy rate. A total of 2,755 nodes (13.78/pt) were identified, of which 494 were SLNs and 2,261 were non-SLNs. Nodal positivity was 46% and 16% for Cca and Rca pts respectively. Mets were detected in 20.9% of SLNs vs. 8.6% of non-SLNs (p< 0.0001). The exclusive site of nodal mets was detected in 6.5% of SLNs vs.0.8% of non-SLNs (p< 0.0001). Skip mets were found in 6% of pts. After ultrastaging all initially -ve non-SLNs (n=2,065), only 0.58% (12/2065) nonSLNs became +ve in 12 pts. Of these, 10 pts already had +ve SLNs, hence no change of staging occurred. Only 2/200 pts (1%) with initially -ve non-SLNs were found to have a cluster of tumor cells. Thus, ultrastaging of 2065 initially -ve non-SLNs in 200 pts changed the staging from II to III only in 1% of pts. Conclusions: SLNM is highly accurate in staging CRca. The chance of finding additional mets by ultrastaging of all non-SLNs is extremely low (< 1%), hence of little benefit. Therefore, ultrastaging restricted to SLNs alone will assure accurate staging of CRca.

[Table: see text]

No significant financial relationships to disclose.

Whole-genome genotyping of haplotype tag single nucleotide polymorphisms

The International HapMap Consortium recently completed genotyping over 3.8 million single nucleotide polymorphisms (SNPs) in three major populations, and the results of studying patterns of linkage disequilibrium indicate that characterization of 300,000–500,000 tag SNPs is sufficient to provide good genomic coverage for linkage-disequilibrium-based association studies in many populations. These whole-genome association studies will be used to dissect the genetics of complex diseases and pharmacogenomic drug responses. As such, the development of a cost-effective genotyping platform that can assay hundred of thousands of SNPs across thousands of samples is essential. In this review, we describe the development of a whole-genome genotyping (WGG) assay that enables unconstrained SNP selection and effectively unlimited multiplexing from a single sample preparation. The development of WGG in concert with high-density BeadChips™ has enabled the creation of three different high-density SNP genotyping BeadChips: the Sentrix™ Human-1 Genotyping BeadChip containing over 109,000 exon-centric SNPs; the HumanHap300 BeadChip containing over 317,000 tag SNPs, and the HumanHap550 Beadchip containing over 550,000 tag SNPs.

Helper-dependent adenoviral gene therapy mediates long-term correction of the clotting defect in the canine hemophilia A model

BACKGROUND

Adenoviral vector-mediated gene therapy might have potential for long-term correction of the monogenic disease hemophilia A.

OBJECTIVE

In this study, we tested the efficacy of administering a helper-dependent adenoviral vector (HDV) designed for maximal liver-restricted canine factor VIII (cFVIII) expression on three out-bred hemophilia A dogs.

METHODS

Three FVIII-deficient animals from the University of North Carolina colony were injected with 1 x 10(12) (Dog A), and 3 x 10(12) (Dog B and C) vp kg(-1) helper-dependent adenoviral vector, and we performed systematic analysis of toxicity, persistence of therapeutic gene expression, and molecular analysis of gene transfer.

RESULTS

We observed acute dose-dependent elevation in liver enzymes and thrombocytopenia after injection, although both were transient and resolved within 2 weeks. The whole blood clotting time (WBCT), plasma FVIII concentration, FVIII activity, and activated partial thromboplastin time in all animals improved significantly after treatment, and two animals receiving a higher dose reached near normal WBCT with low-level FVIII activity until terminal sacrifice at 3 months, and 2 years. Importantly, the treated dogs suffered no bleeding events after injection. Moreover, we observed persistent vector-specific DNA and RNA in liver tissue collected from one high-dose animal at days 18 and 79, and could not detect the formation of inhibitory antibodies.

CONCLUSION

Although vector-associated toxicity remains an obstacle, a single injection of HDV led to long-term transgene expression and vector persistence in two FVIII-deficient animals with conversion of their severe phenotype to a moderate one.

Modulation of TNFalpha, a determinant of acute toxicity associated with systemic delivery of first-generation and helper-dependent adenoviral vectors

Understanding the determinants of the host innate immune response to systemic administration of adenoviral (Ad) vectors is critical for clinical gene therapy. Acute toxicity occurs within minutes to hours after vector administration and is characterized by activation of innate immune responses. Our data indicate that in mice, indicators of vector toxicity include elevations of cytokine levels, liver transaminase levels and thrombocytopenia. To discern potential targets for blunting this host response, we evaluated genetic factors in the host response to systemically administered first-generation Ad vectors (FGV) and helper-dependent Ad vectors (HDV) containing beta-galactosidase expression cassettes. A preliminary screen for modulation of vector-induced thrombocytopenia revealed no role for interferon-gamma, mast cells or perforin. However, vector-induced thrombocytopenia and interleukin 6 (IL-6) expression are less evident in tumor necrosis factor alpha (TNFalpha)-deficient mice. Moreover, we also demonstrated that TNFalpha blockade via antibody or huTNFR:Fc pretreatment attenuates both thrombocytopenia (>40% increase in platelet count) and IL-6 expression (>80% reduction) without affecting interleukin 12 , liver enzymes, hematological indices or vector transduction in a murine model. Our data indicate that the use of HDV, in combination with clinically approved TNFalpha immunomodulation, may represent an approach for improving the therapeutic index of Ad gene therapy for human clinical trials.