Key Challenges for In Vitro Testing of Tobacco Products for Regulatory Applications: Recommendations for the In Vitro Mouse Lymphoma Assay

The Institute for In Vitro Sciences (IIVS) is sponsoring a series of workshops to develop recommendations for optimal scientific and technical approaches for conducting in vitro assays to assess potential toxicity within and across traditional tobacco and various tobacco and nicotine next-generation products (NGPs), including Heated Tobacco Products (HTPs) and Electronic Nicotine Delivery Systems (ENDS). This report was developed by a working group composed of attendees of the seventh IIVS workshop, 'Approaches and recommendations for conducting the mouse lymphoma gene mutation assay (MLA) and introduction to in vitro disease models', which was held virtually on 21-23 June 2022. This publication provides a background overview of the MLA, and includes the description of assay conduct and data interpretation, key challenges and recommended best practices for evaluating tobacco and nicotine products, with a focus on the evaluation of NGPs, and a summary of how the assay has been used to evaluate and compare tobacco and nicotine products.

O086 Genomic analysis of response to neoadjuvant chemotherapy in oesophageal adenocarcinoma

Introduction

Oesophageal adenocarcinoma (OAC) is the ninth most common cancer worldwide with a mortality of over 500,000 deaths yearly. Neoadjuvant chemotherapy (NAC) followed by surgery is the standard of care (SOC) for locally advanced OAC. Although almost all patients receive chemotherapy as SOC, fewer than 20% obtain a clinically meaningful response and benefit before surgery. The OAC genome is complex and heterogeneous between patients, and it is not yet understood whether specific mutational patterns result in chemotherapy sensitivity or resistance.

Methods

To identify associations between genomic events and response to NAC in OAC, a comparative genomic analysis was performed in 65 patients using whole-genome sequencing. We defined response to NAC using Mandard Tumour Regression Grade TRG), with responders classified as TRG1-2 (n=27) and non-responders classified as TRG4- 5 (n=38).

Results

We report a higher non-synonymous mutation burden in responders (median 2.08/Mb vs 1.70/Mb, P=0.036) and elevated copy number variation (CNV) in non-responders (282 vs 136/patient, P<0.001). We identified CNVs unique to each group, with cell cycle (CDKN2A, CCND1), c-Myc (MYC), RTK/PIK3 (KRAS, EGFR) and gastrointestinal differentiation (GATA6) pathway genes being specifically altered in non-responders. Of particular interest was the identification of the Neuron Navigator-3 (NAV3), a known tumour suppressor downstream of EGFR, which was mutated exclusively in 22% of non-responders.

Conclusion

We characterise genetic features and mutations that are uniquely associated with response to NAC. We envision a treatment pipeline that incorporates driver mutation profiling in OAC, combining response prediction with targeted therapies enhancing response to NAC and improving survival outcomes.

Take-home message

Developing a method of determining an OAC patient's response to neoadjuvant chemotherapy before treatment is administered is desperately needed and will improve patient outcome and quality of life. We identified a number of aberrations in the genome that were unique to non-responders to chemotherapy compared to responders, particularly a known tumour suppressor gene namely Neuron Navigator-3, suggesting that these events may contribute to chemoresistance in these patients. Our work characterises pre-existing genomic alterations that have potential as biomarkers for resistance or sensitivity to NAC.

O4 Neural network image capture to predict response of oesophageal adenocarcinoma to neoadjuvant therapy

Introduction

Locally advanced oesophageal adenocarcinoma is typically treated with neoadjuvant chemotherapy (NACT) or chemoradiotherapy (NACRT) followed by surgery. Significant benefit to neoadjuvant treatment however is confined to a minority of patients (<25%) and there are no reliable means of establishing prior to treatment in whom this benefit will occur. In this study, we assessed the utility of features extracted from high-resolution digital microscopy of pre-treatment biopsies in predicting response to neoadjuvant therapy in a machine-learning based modelling framework.

Method

A total of 102 cases were included in the study. Pre-treatment clinical information, including TNM staging, was obtained, along with diagnostic biopsies. Diagnostic biopsies were converted into high-resolution whole slide-images and features extracted using a pre-trained convolutional neural network (Xception). Elastic net regression models were then trained and validated with bootstrapping with 1000 resampled datasets. The response was considered according to Mandard tumour regression grade (TRG).

Result

There were 45 (44.1%) responders (TRG1-2) and 57 (57%) non-responders (TRG3-5) in the dataset. 34 patients (33.3%) received NACT and 68 (66.7%) received NACRT. A model trained with RNA-seq data achieved fair performance only in predicting response (AUC 0.598 95% CI 0.593–0.603), which was far exceeded by use of segmented diagnostic biopsy images (AUC 0.872 95% CI 0.869–0.875), which also produced well calibrated predictions of risk.

Conclusion

Despite using a small dataset, impressive performance in classifying response to neoadjuvant treatment can be achieved, particularly using automated image classification. Further study to refine the methodology is required before expansion to clinical settings.

Take-home Message

Response to neoadjuvant treatment for oesophageal cancer can be predicted from diagnostic biopsies

O29: PREDICTING RESPONSE TO NEOADJUVANT THERAPY IN OESOPHAGEAL ADENOCARCINOMA PRE-TREATMENT BIOPSIES

Aims

We currently cannot predict which patients with locally advanced oesophageal adenocarcinoma will be amongst the 15-20% to gain a clinically important response to neoadjuvant therapy (NAT). This pilot study aimed to identify differentially expressed genes from oesophageal adenocarcinoma pre-treatment biopsies between responders and non-responders to NAT and develop methodology for predicting response.

Method

Response to NAT was assessed pathologically using Tumour Regression Grading (TRG). Pre-treatment formalin-fixed paraffin embedded samples were analysed with two nuclease protection assays (EdgeSeq, HTG = Oncology Biomarker Panel (OBP) and Precision Immuno-Oncology Panel (PIP)). Sequencing was performed on the NextSeq500 (Illumina).

Result

Whilst there was no difference in pre-treatment characteristics, responders (TRG1-2, n=26) had significantly better post-treatment pathology and overall survival than non-responders (TRG4-5, n=30). Genes up-regulated in responders were involved in regulating cell cycling, whereas genes up-regulated in non-responders were involved in cytokine signalling and the immune response. Neuronal artificial network models could predict response to NAT with overall accuracy of 73% and 68% for the OBP and PIP, respectively, which is promising considering the small sample size. As no model will be 100% accurate, we developed a model that could take patient's views into consideration with an adjustable probability threshold for classification.

Conclusion

This pilot study informs a biologically sound hypothesis for the basis of response to NAT and suggests prediction from pre-treatment biopsies may be possible using EdgeSeq. We now aim to validate these results in a larger study to inform a bespoke classifier of response to enable delivery of precision therapy.

Take-home message

In oesophageal adenocarcinoma, responders and non-responders to neoadjuvant therapy have different expression profiles. Through using EdgeSeq in larger studies, we may be able to predict which patients will respond to treatment, allowing for delivery of precision therapy.

O7: APPARENT PATHOLOGICAL COMPLETE RESPONSE TO NEOADJUVANT THERAPY LEADS TO SELECTION OF TREATMENT RESISTANT CANCER STEM CELLS IN OESOPHAGEAL ADENOCARCINOMA

Introduction

In oesophageal adenocarcinoma with an apparent pathological complete response (pCR) to neoadjuvant therapy (NAT) there remains debate as to whether oesophagectomy is required. Single Cell RNA sequencing (scRNAseq) enables identification and characterisation of cell populations at higher resolution than diagnostic techniques.

Method

ScRNAseq was used to determine transcriptomic profiles of cell populations in 24 OAC tumours and 13 matched normal samples. Five were also analysed using bulk RNA sequencing and high-precision mass spectrometry proteomics. Immunohistochemistry (IHC) was used to validate pCR. Paired scRNAseq analysis of pre-and post-treatment specimens from three further patients was used to compare transcriptomic profiles before and after NAT. Cancer cells (CCs) were assigned a cancer stem cell (CSC) score curated from published gene sets.

Result

We analysed a total of 22,738 single cells forming 29 different cell phenotypes. In two samples with apparent pCR, IHC staining, bulk RNA sequencing and proteomics of post-treatment samples failed to identify CCs. ScRNAseq, conversely, revealed persistent CCs (12/978 and 45/774). Transcriptomic analysis identified upregulation of stem cell markers and high CSC scores in these cells.

Conclusion

We have shown that CCs persist beneath the lower detection limit of standard approaches in apparent pCR. These cells express marker genes and expression programs consistent with CSCs. CSCs are a critical subpopulation that drive tumour initiation, growth, invasion, metastasis and resistance to therapy. These gene expression programs are not enriched in non-responders and straight to surgery samples. Oesophagus sparing treatment algorithms in pCR may subject patients to unnecessary risk of progression.

Take-home message

Cancer cells remain within tumours after apparent complete pathological response. These cells express stem cell markers associated with resistance to therapy and cancer progression.

A mixed-methods evaluation of the impact of a pharmacist-led feedback pilot intervention on insulin prescribing in a hospital setting

AIMS

To explore the impact of a prescribing feedback intervention on insulin prescribing.

METHODS

This was a mixed-methods study in a hospital setting. An insulin prescribing feedback intervention was delivered verbally and in writing to twelve doctors. Insulin prescribing error frequency was compared to ten doctors who had not received the feedback intervention. Insulin prescribing was audited over four weeks at the start and end of the intervention period. Semi-structured interviews were conducted with participating doctors who had received feedback, and qualitative data analysed thematically to explore the impact of the intervention on their prescribing practice.

RESULTS

Prescribing data were collected on 370 insulin prescriptions with 241 errors identified. A significant reduction (χ2 = 22.6, p=<0.05) in insulin prescribing error frequency was observed in the intervention group, with a non-significant increase reported in the control group. Feedback was received positively and considered valuable by doctors, supporting development of their knowledge and skills and encouraging reflection on their prescribing performance. Doctors described enhanced confidence in insulin prescribing and a desire to improve as a prescriber and avoid harm, with feedback raising awareness of their development needs. Prescribers also described enhanced team work, with greater information and feedback seeking behavior to inform future prescribing decisions.

CONCLUSIONS

Feedback has potential to improve insulin prescribing and is a valued and acceptable process intervention for doctors. The impact on insulin prescribing practice is varied and complex influencing the capability, opportunity and motivation of prescribers to adapt and evolve their behavior in response to ongoing feedback.

Absence of genotoxicity of purified Aloe vera whole leaf dry juice as assessed by an in vitro mouse lymphoma tk assay and an in vivo comet assay in male F344 rats

Hydroxyanthracene derivatives (HAD) are naturally present in the latex layer of Aloe vera leaf, predominantly as aloins A, B and aloe-emodin. HAD are typically removed from commercial ingestible aloe products through activated charcoal filtration (decolorization). Current research aimed to evaluate genotoxic potential of a purified aloe whole leaf dry juice containing 0.3 ppm of total aloins and non-detectable aloe-emodin (LOD =0.01 ppm) in the L5178Y mouse lymphoma assay (MLA; OECD 490) and in vivo comet assay (OECD 489). No marked increases in mutant frequency at the tk locus were observed in the MLA at concentrations up to 5000 μg/mL for 3 h and 24 h (-S9), and up to a precipitating concentration of 3000 μg/mL for 3 h (+S9) compared to concurrent vehicle control. Relative total growth at the highest analyzable concentrations at 3 h (±S9) and 24 h (-S9) ranged from 64 to 133 %. In the comet assay, no statistically significant increases in DNA strand breaks were detected in the colon or kidney following oral gavage of 500, 1000 or 2000 mg/kg/day in male F344 rats for 2 days compared to concurrent vehicle control. Overall, these findings demonstrated the test article containing minimal HAD is not genotoxic under the described experimental conditions.

Evaluating the impact of a pharmacist-led prescribing feedback intervention on prescribing errors in a hospital setting

BACKGROUND

Prescribing errors are prevalent in hospital settings with provision of feedback recommended to support prescribing of doctors. Feedback on prescribing has been described as feasible and valued but limited by doctors, with pharmacists described as credible facilitators of prescribing feedback. Evidence supporting prescribing feedback has been limited to date. A formalised programme of pharmacist-led prescribing error feedback was designed and implemented to support prescribers.

OBJECTIVE

To evaluate the impact of a prescribing feedback intervention on prescribing error rates and frequency of prescribing error severity and type.

METHOD

Prospective prescribing audits were undertaken across sixteen hospital wards in a UK teaching hospital over a five day period with 36 prescribers in the intervention group and 41 in the control group. The intervention group received pharmacist-led, individualised constructive feedback on their prescribing, whilst the control group continued with existing practice. Prescribing was re-audited after three months. Prescribing errors were classified by type and severity and data were analysed using relevant statistical tests.

RESULTS

A total of 5191 prescribed medications were audited at baseline and 5122 post-intervention. There was a mean prescribing error rate of 25.0% (SD 16.8, 95% CI 19.3 to 30.7) at baseline and 6.7% (SD 9.0, 95% CI 3.7 to 9.8) post-intervention for the intervention group, and 19.7% (SD 14.5, 95% CI 15.2 to 24.3) at baseline and 25.1% (SD 17.0, 95% CI 19.8 to 30.6) post-intervention for the control group with a significant overall change in prescribing error rates between groups of 23.7% (SD 3.5, 95% CI, -30.6 to -16.8), t(75) = -6.9, p < 0.05. The frequency of each error type and severity rating was reduced in the intervention group, whilst the error frequency of some error types and severity increased in the control group.

CONCLUSION

Pharmacist-led prescribing feedback has the potential to reduce prescribing errors and improve prescribing outcomes and patient safety.

AB0891 BARE TO THE BONE - AN AUDIT OF RENAL BONE DISEASE AGAINST KDIGO GUIDELINES

Background:

Chronic kidney disease-mineral and bone disorder (CKD-MBD) is complex and management can be difficult. We aimed to compare management of our CKD patients to 2018 KDIGO guidelines. The guidelines suggest checking calcium and phosphate (Ca/PO4) within 12 mths in CKD 3a and 3b, within 6 mths for CKD 4, and within 3 mths for CKD 5. Parathyroid hormone (PTH) should be checked at baseline in CKD 3a-b, within 12 mths in CKD 4 and within 6mths in CKD 5. Alkaline phosphatase (ALP) should be measured within 12 mths in CKD 4 and 5. 25-(OH)D levels ‘might’ be measured at baseline in CKD 3a to 5D. BMD scanning is suggested if the result will impact treatment decisions. Lateral abdominal X ray is recommended as an alternative to CT for detection of vascular calcification. Calcitriol and vitamin D analogues are no longer routinely advised in CKD 3a-5; 25-(OH)D insufficiency should be corrected as in the normal population.

Objectives:

To compare management of our CKD patients to 2018 KDIGO guidelines

Methods:

We randomly selected 70 patients in whom data was available from renal clinics between May and September 2019.

Results:

Mean age was 67.3 yrs. 41 male, 29 female. 33 patients had CKD 3a-b; 31 had CKD 4; 6 had CKD 5. Mean duration of CKD was 10.6 yrs. 10 patients were taking activated vitamin D analogues; 13 were taking 25-(OH)D analogues. 25-(OH)D levels ranged from 24-158 nmol/L (mean 65nmol/L). PTH levels ranged from 2- 69pmol/L (mean 23pmol/L). 3 patients were taking bisphosphonates. 44 had previous lumbar spinal imaging; vertebral fractures were evident in 4 (9%). 12 patients had had DXA scans; lowest T score was -2.5. Table 1 - tests within suggested time frames:

CKD 3a-3bCKD 4CKD 5Ca/ PO433 (100%)29 (93%)6 (100%)ALP33 (100%)31 (100%)6 (100%)PTH14 (42%) (ever)8 (26%)3 (50%)25-(OH)D8 (24%) (ever)8 (26%) (ever)1 (14%)(ever)

Conclusion:

Optimum PTH levels in CKD patients are not known, and therapeutic options in CKD-MBD often limited. Nevertheless, our results suggest that bone biochemistry could be checked more consistently in CKD patients. Although detection of vascular calcification may not alter renal management, abdominal imaging provides an opportunity to screen for vertebral fracture, present in a significant number of our patients. The KDIGO guidelines offer a framework to work with our renal colleagues, as many patients will be jointly managed.

References:

[1]Diagnosis, Evaluation, Prevention, and Treatment of Chronic Kidney

[2]Disease–Mineral and Bone Disorder: Synopsis of the Kidney Disease:

[3]Improving Global Outcomes 2017 Clinical Practice Guideline Update. Ann Int Med 2018

Disclosure of Interests:

NATALIA CERNOVSCHI: None declared, SHABEENA ZEB: None declared, TRACEY SALTER: None declared, MARK LLOYD Speakers bureau: £700 into department fund

THU0589 ‘KU FEVER’: A CASE REPORT

Background:

Anti-Ku antibodies have been associated with various connective tissue diseases, including myositis, arthritis, interstitial lung disease and glomerulonephritis1.

Objectives:

We present a case of a woman initially diagnosed with biopsy proven Kikuchi-Fujimoto disease who later developed a rapidly progressive myositis in association with anti-Ku antibodies.

Methods:

A 47 year-old woman, originally from Myanmar, presented with lymphadenopathy, myalgia, fatigue, livedo reticularis and low-grade fever for the previous 6 months. This was initially diagnosed as a viral infection. Her myalgia progressed with proximal muscle weakness in both legs and associated rise in creatine kinase levels to 349U/L (normal range 25-200). She also developed dyspnoea, an erythematous rash, mouth ulcers and unintentional weight loss.

Blood tests show a lymphopenia and progressively rising CK, with a maximum level of 516 U/L. MRI whole body confirmed a widespread diffuse myositis in her upper and lower limbs, with an unusual ‘speckled’ pattern. High resolution CT Chest was normal. C3 0.40 g/l (normal range 0.75-1.65) and C4 0.12 g/l (0.14-0.54) were low, with a positive ANA (1:160) and Ro-60 antibody. dsDNA, antiphospholipid screen and virology screens were all negative. Extended myositis panel revealed positive anti-Ku antibodies. Axillary lymph node biopsy confirmed necrotising lymphadenitis, consistent with Kikuchi-Fujimoto disease.

Results:

She was initially treated with low dose Prednisolone and Hydroxychloroquine, with a limited response. Due to progressive myositis, pulsed IV Methylprednisolone 1g was provided over 3 days and mycophenolate mofetil (MMF) was started.

An inpatient stay was needed after developing an axillary node abscess and a chest infection. This was treated with intravenous antibiotics and repeated aspirations. Due to progressive myositis on a background of sepsis, intravenous immunoglobulin (IVIG) was administered over 5 days. Our patient made a good recovery, with normalization of CK levels and resolution of the myositis noted on repeat MRI scan. She remains on MMF as maintenance therapy.

Conclusion:

Anti Ku antibodies appear to be associated with 2 spectrums of disease – elevated CK levels with interstitial lung disease and renal disease associated with anti-dsDNA antibodies1To our knowledge this is the first report in association with Kikuchi-Fujimoto disease. The combination of MMF and IVIG appears to have been effective treatment and her renal function remains stable, although we are monitoring the patient carefully for the possible development of interstitial lung disease.

References:

[1]Spielmann L, Nespola B, Séverac F, et al. Anti-Ku syndrome with elevated CK and anti-Ku syndrome with anti-dsDNA are two distinct entities with different outcomes. Annals of the Rheumatic Diseases 2019;78:1101-1106.

Disclosure of Interests:

None declared

THU0291 IS GIANT CELL ARTERITIS REALLY GIANT CELL ARTERITIS? A HISTOLOGICAL REVIEW OF TEMPORAL ARTERY BIOPSIES FROM A UK DISTRICT GENERAL HOSPITAL

Background:

Despite the advent of newer imaging techniques, temporal artery biopsy (TAB) retains a key role in the diagnosis of giant cell arteritis (GCA). The classical histological description of GCA is that of granulomatous lesions characterized by a transmural inflammatory infiltrate1. Giant cells are typically noted in the internal elastic lamina. Vascular remodeling and structural changes are also frequently described, with intimal hyperplasia or fragmentation, fibrosis and calcifications1.

Objectives:

To identify the type and location of the inflammatory lesions in TAB-positive cases of GCA.

Methods:

We conducted a retrospective analysis of all TABs undertaken at our unit between 2011- 2018 with clinical record review. TABs were performed by vascular, ophthalmology and ENT teams.

Results:

379 TABs were reviewed of which 68 (17.9%) were reported as positive and 10 (2.6%) were equivocal (presence of fragmentation and intimal thickening). Of the TAB-positive cases, 43 (63.2%) were greater than 1cm in keeping with the British Society for Rheumatology guidance and 65 (95.6%) were biopsies in patients on corticosteroids at the time of procedure. The following tables demonstrate the frequency of the type and location of the inflammatory lesions detected in TAB-positive cases of GCA.

Type of inflammatory lesionFrequencyChronic inflammatory infiltrate (lymphocytes, macrophages, plasma cells)66Giant cells41Intimal thickening22Intimal fragmentation33Location of inflammatory infiltrateFrequencyFull thickness32Intima only7Intima and Media only3Media only7Media and Adventitia only8Adventitia only4Intima and Adventitia only3Not recorded4

Conclusion:

Only 60% of our TAB-positive biopsies had giant cells present. Although perhaps surprisingly low, this finding is similar to other studies1,2. It emphasises the need to review the body of a report as well the conclusion. Other non-giant cell features present in positive reported biopsies may suggest a less certain diagnosis and prompt clinical review. There was considerable variablity in the style of reporting. With no standardised scoring system in place, the variable spectrum of inflammation and differences in reporting, there is the potential for inconsistencies amongst pathologists in interpreting and recording TAB results. Consistent reporting templates and close collaboration between rheumatologists and pathologists is needed to help correlate clinical, laboratory and imaging findings.

References:

[1]Cavazza A, Muratore F, Boiardi L, Restuccia G, Pipitone N, Pazzola G, et al. Inflamed temporal artery: histologic findings in 354 biopsies, with clinical correlations. Am J Surg Pathol. 2014;38(10):1360-70.

[2]Hernandez-Rodriguez J, Murgia G, Villar I, Campo E, Mackie SL, Chakrabarty A, et al. Description and Validation of Histological Patterns and Proposal of a Dynamic Model of Inflammatory Infiltration in Giant-cell Arteritis. Medicine (Baltimore). 2016;95(8):e2368.

Disclosure of Interests:

Soha Khaled Amar: None declared, Dimitrios Christidis: None declared, George Kousparos: None declared, MARK LLOYD Speakers bureau: £700 into department fund

Inclusion of an extended treatment with recovery improves the results for the human peripheral blood lymphocyte micronucleus assay

The in vitro micronucleus (IVMN) test was endorsed for regulatory genotoxicity testing with adoption of the Organisation for Economic Co-operation and Development (OECD) test guideline (TG) 487 in 2010. This included two equally acceptable options for extended treatment in the absence of metabolic activation: a treatment for 1.5-2.0 cell cycles with harvest at the end of treatment (Option A) or treatment for 1.5-2.0 cell cycles followed by recovery for 1.5-2.0 cell cycles prior to harvest (Option B). Although no preferences were discussed, TG 487 cautions that Option B may not be appropriate for stimulated lymphocytes where exponential growth may be declining at 96 h after phytohaemagglutinin (PHA) stimulation. Following revision of TG 487 in 2014 and 2016, emphasis has been placed on using Option A. Given the purpose of the IVMN assay is to determine both clastogenic and aneugenic potential, the authors believe the assay is compromised if an extended treatment with recovery is not included for sensitive detection of certain classes of chemical. In this study, average generation time (via bromodeoxyuridine incorporation) of human peripheral blood lymphocytes (HPBL) was measured up to 144 h after PHA stimulation. In addition, the HPBL micronucleus (MN) assay was performed using Option A and B treatment schedules. Cytotoxicity (replication index) and MN induction were determined following treatment with 14 chemicals. The data demonstrate that lymphocytes actively divide beyond 96 h after PHA stimulation. Furthermore, MN induction was only observed with some aneugenic chemicals and nucleoside analogues in HPBLs following extended treatment with a recovery period. For the majority of chemicals tested the magnitude of MN induction was generally greater and MN induction was observed across a wider concentration range following the Option B treatment schedule. In addition, steep concentration-related toxicity following treatment without recovery is more common, making selection of suitable concentrations (within regulatory toxicity limits) for MN analysis challenging.

Genotoxicity evaluation of tobacco and nicotine delivery products: Part One. Mouse lymphoma assay

Conduct of the mouse lymphoma assay (MLA) is underpinned by Organisation for Economic Co-operation and Development (OECD) Test Guideline 490 and International Conference on Harmonisation S2(R1) guidance and is a recognised in vitro genotoxicity test battery assay. It has been used on a limited number of occasions for the assessment of some tobacco and nicotine products, such as e-cigarettes and tobacco heating products (THP). The aim of this study was to assess the suitability of the MLA for genotoxicity testing with a variety of tobacco and nicotine products. Total particulate matter (TPM) from a 3R4F cigarette was compared against a commercial electronic cigarette liquid (e-liquid), electronic cigarette (e-cigarette) aerosol matter captured from the same e-liquid, and TPM from a commercial THP. Treatment conditions included 3 h exposures with and without metabolic activation and a longer 24 h exposure without metabolic activation (-S9) at concentrations up to 500 μg/mL. Under all treatment conditions, 3R4F produced a clear positive response with regard to induction of mutation. In contrast, no marked induction of mutation was observed for the e-liquid, e-cigarette aerosol or THP. Additionally, data are presented as a function of nicotine equivalents for comparisons between these different tobacco products and test matrices.

Genotoxicity evaluation of tobacco and nicotine delivery products: Part Two. In vitro micronucleus assay

In this study, a variety of test matrices from tobacco and nicotine delivery products were assessed against a 3R4F Kentucky reference cigarette using the in vitro micronucleus assay. Testing was conducted using two Chinese hamster cell lines (CHO and V79), and a human lymphoblastoid cell line (TK6), in accordance with established guidelines. Total particulate matter (TPM) from a 3R4F Reference cigarette was compared to an electronic cigarette e-liquid, electronic cigarette TPM and TPM from a commercial tobacco heating product using a standard and an extended treatment condition with recovery period. Cells were assessed with 3R4F TPM prior to assessment of the other tobacco and nicotine product test matrices. These cell lines gave varied responses to 3R4F TPM with the most robust response using V79 cells. The use of an extended exposure/recovery period was seen to increase assay sensitivity for CHO and V79 cell lines but was less clear for TK6 cells. Negative responses were observed for all products except 3R4F across all treatment conditions in V79 cells. The most potent response to cigarette smoke was following extended treatment with recovery, suggesting this may be a more appropriate treatment for the future assessment of tobacco and nicotine product test matrices.

Asthma prevalence and control levels among Special Olympics athletes, and asthma-related knowledge of their coaches

BACKGROUND

The prevalence of asthma among athletes with intellectual disabilities, and the asthma knowledge levels of their coaches, is unknown.

METHODS

Special Olympics Canada athletes completed a demographic questionnaire (n = 208). Athletes who identified as having ever or current asthma completed the Asthma Control Questionnaire and the Mini Asthma Quality of Life Questionnaire and were measured for height, weight and lung function (n = 73). National level coaches (n = 27) completed a questionnaire pertaining to asthma knowledge.

RESULTS

The prevalence of ever and current asthma were 35.5% (n = 73) and 21.1% (n = 44), respectively. Athletes with asthma reported that they had inadequately controlled asthma, but good quality of life. Coaches correctly answered 43% true/false questions on the survey, indicating suboptimal asthma knowledge.

CONCLUSIONS

Athletes with intellectual disabilities appear to have a greater prevalence of asthma than the general population; however, coaches of these athletes appear to have limited knowledge pertaining to asthma and exercise-induced asthma.

Abstract PD9-02: Evolutionary analysis of 462 serial metastatic biopsies from 208 patients with estrogen receptor-positive (ER+) metastatic breast cancer (MBC) using whole exome sequencing (WES)

Background: While great strides have been made in the treatment of ER+ MBC, therapeutic resistance is nearly universal. The genomic evolution of ER+ breast cancer in the metastatic setting under the selective pressure of multiple lines of therapies is not well understood. To address this, we analyzed the clonal dynamics of serial metastatic samples (mets) to evaluate how tumors evolve and to identify acquired resistance mechanisms.

Methods: We performed WES on 462 clinically annotated samples from 208 patients (pts) with ER+ MBC, including 67 primary tumor biopsies, 229 metastatic biopsies and 160 blood samples (cfDNA). Pts with multiple mets included cases with temporally concordant metastatic tumor and blood samples (48 pts) and cases with serial mets obtained over the course of treatment in the metastatic setting (69 pts). Treatments given between the serial mets included CDK4/6 inhibitors (23 pts), and selective estrogen receptor degraders (19 pts), among others.

Results: In the temporally-concordant mets, we found that cfDNA mutations (muts) largely overlap with muts found in tumor biopsies, capturing &gt;85% of clonal tumor muts. However, we observed a higher level of heterogeneity in cfDNA compared to biopsies (p.value&lt; 1.05e-19, Welch test) and a subset of high-confidence muts that were only detected in cfDNA, including in clinically important genes such as ESR1, PIK3CA, KRAS, and ERBB2. Analysis of serial mets was used to elucidate the evolutionary dynamics within the metastatic setting under the selective pressure of treatment. The median duration between mets was 112 days and the median number of inter-biopsy unique treatments was two. Most tumors continued to evolve within the metastatic setting, with 50 out of 69 pts (72%) acquiring a meaningful sub-clone (50% increase in relative cancer cell fraction) and 31 out of 69 (45%) acquiring muts in known cancer genes, including a subset acquiring a plausible resistance alteration such as alterations that dysregulate ER (5 out of 69 pts, 7%; ESR1 mut, FOXA1 amplification (amp), NCOR1 bi-allelic deletion (del)), ERBB (4%; ERBB2 amp, ERBB3 mut), RAS (4%; KRAS mut, NRAS amp, NF1 del), FGF/FGFR (12%; FGFR2 mut, FGFR1/2 amp, FGF3 amp), and cell cycle (13%; RB1 del, CDK4 amp, AURKA amp, CDKN2A del). Finally, in pts who had multiple mets, we observed several cases of evolutionary convergence toward equivalent resistance mechanisms including convergent RB1 loss as a mechanism of resistance to a CDK4/6 inhibitor and convergent BRCA2 reversion following resistance to a PARP inhibitor.

Conclusions: This study demonstrates that ER+ MBC continues to evolve under the selective pressure of treatments in the metastatic setting. These findings elucidate the challenge of studying high complexity and heavily treated tumors, while also highlighting some commonalities in the evolutionary trajectories selected by these treatments. The multiplicity of clinically relevant genomic alterations acquired in these advanced stages highlights the need for serial biopsies and the potential to inform post-progression therapeutic choices through targeting the acquired dependencies in post-progression tumors.

Citation Format: Cohen O, Buendia-Buendia J, Wander S, Nayar U, Mao P, Waks A, Kim D, Freeman S, Adalsteinsson V, Helvie K, Livitz D, Rosebrock D, Leshchiner I, Dellostritto L, Garrido-Castro A, Jain E, Periyasamy S, Mackichan C, Lloyd M, Marini L, Krop I, Garraway L, Getz G, Winer E, Lin N, Wagle N. Evolutionary analysis of 462 serial metastatic biopsies from 208 patients with estrogen receptor-positive (ER+) metastatic breast cancer (MBC) using whole exome sequencing (WES) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD9-02.

Abstract P5-21-10: Phase 2 study and correlative analyses of ruxolitinib, a selective JAK1/2 inhibitor, in patients with metastatic, triple-negative breast cancer

Background: Preclinical data supports a role for the IL-6/JAK2/STAT3 signaling pathway in breast cancer (BC). Ruxolitinib is an orally bioavailable receptor tyrosine inhibitor targeting JAK1 and JAK2. We evaluated the safety and efficacy of ruxolitinib in patients with metastatic BC and performed correlative analyses.

Methods: This was a non-randomized, phase 2 study of patients with refractory, metastatic, triple-negative BC (TNBC). Patients with inflammatory BC (IBC) of any subtype were also enrolled. The primary endpoint was objective response by RECIST 1.1. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and toxicity. The study was designed to enroll only patients whose archival tumor tissue was pSTAT3 moderately to strongly positive in the tumor epithelial cells by central immunohistochemistry (IHC). 16 patients underwent pre-treatment biopsy, of whom 4 also had a second biopsy prior to cycle 2. Biopsy samples and paired primary tumor samples (when available) were subjected to multi-color immunofluorescence and/or immune-FISH for leukocyte markers, pSTAT3, and JAK2. RNA sequencing was performed on available on-study frozen biopsy specimens. 17 patients had plasma collected with cell-free DNA (cfDNA) extracted and subjected to low coverage whole-genome sequencing.

Results: Of 217 patients who consented to archival tumor testing, T-score for pSTAT3 was 'high' (&gt;5) in 69 patients (31.8%), demonstrating frequent activation of the JAK/STAT pathway in metastatic TNBC or IBC. 23 pSTAT3 high patients were enrolled. Ruxolitinib was generally well-tolerated. The most commonly observed adverse events (any grade) were anemia, neutropenia, thrombocytopenia, constipation, nausea, and increased AST/ALT. Grade 3 or higher toxicities were uncommon. No objective responses were seen among 21 evaluable patients, therefore the study was closed to accrual based on study design. Intensive correlative analyses revealed important insights regarding ruxolitinib effects. Pharmacodynamic analyses of baseline versus cycle 2 biopsies demonstrate downregulation of JAK2 target genes, STAT3 signatures, and JAK/STAT gene ontology gene sets, suggesting on-target activity. There was evidence of immune microenvironment modulation: gene set enrichment analysis implicated reduced macrophage/myeloid phenotypes after treatment and CIBERSORT analysis of inferred immune cell subsets demonstrated reduced monocyte/macrophage proportion after treatment (t-test p=0.013). Multi-color immunofluorescence analyses of immune microenvironment are ongoing and will be reported. 17 patients underwent cfDNA analysis with 8 patients (47%) demonstrating gain or amplification of JAK2.

Conclusions: Ruxolitinib, as a single agent, did not meet the primary efficacy endpoint in this refractory patient population. Correlative studies demonstrate evidence of on-target activity and immune microenvironment modulation. Frequent JAK/STAT pathway activation and JAK2 locus chromosomal gains in this cohort suggest that the JAK/STAT pathway remains a potential therapeutic target in BC.

Citation Format: Stover DG, Gil Del Alcazar CR, Tolaney SM, Bardia A, Guo H, Balko JM, Overmoyer BA, Gelman RS, Lloyd M, Wang V, Brock JE, Winer EP, Polyak K, Lin NU. Phase 2 study and correlative analyses of ruxolitinib, a selective JAK1/2 inhibitor, in patients with metastatic, triple-negative breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-21-10.

Abstract S1-01: Whole exome and transcriptome sequencing of resistant ER+ metastatic breast cancer

Background: While great strides have been made in the treatment of estrogen receptor-positive (ER+) metastatic breast cancer (MBC), therapeutic resistance invariably occurs. A better understanding of the underlying resistance mechanisms is critical to enable durable control of this disease.

Methods: We performed whole exome sequencing (WES) and transcriptome sequencing (RNA-seq) on metastatic tumor biopsies from 88 patients with ER+ MBC who had developed resistance to one or more ER-directed therapies. For 27 of these patients, we sequenced the treatment-naïve primary tumors for comparison to the resistant specimens. Tumors were analyzed for point mutations, insertions/deletions, copy number alterations, translocations, and gene expression. Detailed clinicopathologic data was collected for each patient and linked to the genomic information.

Results: WES of all metastatic samples demonstrated several recurrently altered genes whose incidence differed significantly from primary, treatment-naïve ER+ breast cancers sequenced in the TCGA study (TCGA). These include ESR1 mutations (n=17, 19.3%; 32.86 fold enrichment, q.value&lt;7.5e-12), CCND1 amplification (n=52, 59.1%; 2.3 fold enrichment, q.value&lt;0.0073), and MAP2K4 biallelic inactivation (n=14, 15.9%; 3.04 fold enrichment, q.value&lt; 0.054).

Comparing to matched primary samples from the same patient, many alterations were found to be acquired in several cases, including for ESR1, ERBB2, PIK3CA, PTEN, RB1, AKT1, and others. Initial analysis of RNA-seq data from metastatic samples (n=59) allowed classification of individual resistance mechanisms into broader resistance modes based on the observed transcriptional state.

Conclusions: We present a genomic landscape of resistant ER+ MBC using WES and RNA-seq. Multiple genes were recurrently altered in these tumors at significantly higher rates than in ER+ primary breast cancer. When compared with matched primary tumors from the same patient, alterations in these and other genes were often found to be acquired after treatment, suggesting a role in resistance to ER-directed therapies and/or metastasis. Potential resistance mechanisms appear to fall into several categories; integrating RNA-seq data may enhance the ability to identify these categories even when genomic alterations are not identified. Multiple clinically relevant genomic and molecular alterations are identified in metastatic biopsies– with implications for choice of next therapy, clinical trial eligibility, and novel drug targets.

Citation Format: Cohen O, Kim D, Oh C, Waks A, Oliver N, Helvie K, Marini L, Rotem A, Lloyd M, Stover D, Adalsteinsson V, Freeman S, Ha G, Cibulskis C, Anderka K, Tamayo P, Johannessen C, Krop I, Garraway L, Winer E, Lin N, Wagle N. Whole exome and transcriptome sequencing of resistant ER+ metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S1-01.

Formalized prescribing error feedback from hospital pharmacists: doctors' attitudes and opinions

Doctors have reported a lack of awareness of their prescribing errors with lack of feedback considered a system failure. This article summarizes the views of hospital doctors about receiving formal prescribing error feedback from ward-based pharmacists.

Abstract P1-12-08: Factors associated with delays in chemotherapy initiation among patients with breast cancer

Background: National guidelines endorse time-dependent quality metrics for breast cancer care. We examined factors associated with delays in chemotherapy initiation at an NCI designated comprehensive cancer center.

Methods: We identified 523 patients who received post-operative adjuvant chemotherapy between January 2011 and December 2013 at our center. We defined 28 days from last definitive surgery (LDS) to chemotherapy as the target timeframe, and unacceptable delay in chemotherapy initiation (UCD) as more than 42 days from LDS. Multivariate regression models were used to identify factors associated with UCD and the impact of Oncotype testing in HR+ patients.

Results: Median days between LDS and chemotherapy initiation was 34 (IQR 15), with 30% of patients starting within 28 days of LDS and 23% having UCD (Table 1). Tumor characteristics such as subtype and stage affected UCD; patients with HR+ or HER2+ tumors were more likely to be delayed compared to those with TNBC. Patients with stage I disease were more likely to be delayed as well as patients undergoing mastectomy or mastectomy with reconstruction. Patients whose pathology sign-out was more than 10 days post-operatively were more likely to be delayed. A higher proportion of UCD was found in HR+ patients (31%) who received an Oncotype recurrence score compared to those who did not (20%).

Table 1: Factors associated with delays in chemotherapy initiation N% DelayOdds Ratio95% CITotal52323  Age&lt;4068191.00.5-2.340 to 49165161.0--50 to 59150252.01.1-3.660 to 69113282.51.3-5.070+27374.11.4-12.3RaceWhite424221.0--Non-White79271.50.8-2.7Missing20251.10.4-3.3InsurancePrivate419211.0--Public104321.60.8-2.9StageI208211.0--II243281.30.8-2.1III72110.30.1-0.7Tumor SubtypeHER2-/HR-105151.0--HR+HER2-264242.11.1-4.2HER2+154272.01.0-3.9Surgery TypeLumpectomy265161.0--Mastectomy89292.51.3-4.5Mastectomy with Immediate Reconstruction169313.31.9-5.6Pathology Sign-Out (&gt;10 days)No331191.0--Yes192322.01.3-3.2Post-Op ComplicationsNo506221.0--Yes17412.20.7-6.6Clinical trial considerationNo435231.0--Yes88240.90.5-17

Conclusions: This study provides insight into populations that may be at risk to experience delays in chemotherapy initiation, directing interventions to improve the timeliness of care.

Citation Format: Losk K, Vaz Duarte Luis I, Camuso K, Lloyd M, Kadish S, Hirshfield-Bartek J, Cutone L, Golshan M, Lin N, Bunnell C. Factors associated with delays in chemotherapy initiation among patients with breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-12-08.

Abstract OT2-05-03: The metastatic breast cancer project: A national direct-to-patient research initiative to accelerate genomics research

Over the past decade, genomic characterization of tumors has shed enormous light on the molecular underpinnings of cancer. These discoveries have led to the development of novel therapies and preventive measures that have already revolutionized cancer care. Despite this progress, the genomics of metastatic breast cancer (MBC), one of the leading causes of cancer death in the U.S., remains poorly understood.

The challenge in studying tumor samples from patients with MBC has been that the tumors from most patients are not available for research, largely because the vast majority of patients are cared for in community settings where genomics studies are not typically conducted. To address this, we have launched a nationwide study, The Metastatic Breast Cancer Project, which seeks to empower patients to accelerate cancer research through sharing their samples and clinical information. We have developed an outreach program in collaboration with MBC advocacy organizations to connect MBC patients around the country with genomics research performed at the Broad Institute, allowing them to participate regardless of where they live.

Working with MBC patients and advocates, we designed a website (www.mbcproject.org) with an online questionnaire that allows patients with MBC to provide information about themselves and their cancer. Based on their answers, patients are offered an electronic consent form that explains the risks and benefits of the study and asks for permission to obtain a portion of their stored tumor tissue, a saliva sample, and copies of their medical records. For patients who consent, our clinical research team contacts their physicians and obtains copies of their medical records, which are reviewed to confirm eligibility. Enrolled patients are sent a saliva kit and asked to mail back a saliva sample, which is used to extract germline DNA. The clinical research team also contacts the patient's pathology department and requests a portion of the tumor to be sent to the Broad Institute for genomic analysis. Whole exome and transcriptome sequencing is performed on tumor and germline DNA. Sequencing data are linked to de-identified clinical information, and the resulting data are used to identify drivers of tumorigenesis, mechanisms of response and resistance to therapies, and diagnostic, prognostic, and therapeutic biomarkers. The database of clinically annotated genomic information will be shared with the NIH and the cancer research community. Study updates and discoveries are shared at regular intervals with all patients who complete the initial questionnaire.

This direct-to-patient approach should be particularly enabling for the identification of patients with rare phenotypes or clinical behavior. For this reason, the first cohorts being studied are patients with extraordinary responses to therapies and patients who present with de novo MBC. Additional cohorts will be added in the future, including young women with MBC and patients with drug-resistant MBC. This project seeks to establish a patient-researcher partnership to accelerate genomic discoveries and improve outcomes in MBC, and may ultimately serve as a means to build a new clinical and translational research model for all patients with cancer.

Citation Format: Wagle N, Painter CA, Ilzarbe M, Van Allen EM, Frank E, Oh C, Krevalin M, Lloyd M, Anderka K, Kryukov G, Boehm JS, Winer E, Lander ES, Golub TR. The metastatic breast cancer project: A national direct-to-patient research initiative to accelerate genomics research. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT2-05-03.

Plateau of adiposity in Australian children diagnosed with Type 1 diabetes: a 20-year study

AIMS

To examine temporal trends in anthropometry in children with Type 1 diabetes from Sydney, Australia.

METHODS

We conducted a retrospective study in a total of 1975 children with Type 1 diabetes, aged <16 years, between 1990 and 2009. Trends in height, weight and BMI standard deviation score after initial stabilization were examined by age group (<5 years, 5 to <10 years, 10 to 16 years) and time period of diagnosis (T1: 1990-1994, T2: 1995-1999; T3: 2000-2004 and T4: 2005-2009). Factors associated with BMI standard deviation score (time period, age group, gender and socio-economic status) were examined using multivariable linear regression.

RESULTS

The mean BMI standard deviation score (±sd) increased between T1 and T2 (0.54 ± 1.14 vs 0.81 ± 1.14, P = 0.002), but remained steady thereafter (T3: 0.85 ± 1.11, T4: 0.87 ± 1.09; T2 to T4: P = 0.40). Similarly, the prevalence of overweight and obesity increased from T1 to T2 (26 to 35%, P = 0.01), but was unchanged thereafter (T3: 34%, T4: 34%; T2 to T4: P = 0.90). On multivariable regression analysis, a higher BMI standard deviation score was associated with younger age (≥5 years vs <5 years, β=-0.40, 95% CI -0.51 to -0.28, P < 0.001), later time period (T2 to T4 vs T1, β=0.30, 95% CI 0.16-0.45, P < 0.001) and male gender (β=0.25, 95% CI 0.15-0.34, P < 0.001).

CONCLUSION

The prevalence of overweight and obesity has remained unchanged in children at diagnosis of Type 1 diabetes over 15 years. These findings suggest that higher adiposity alone cannot account for the continued rising incidence of Type 1 diabetes in recent years.

Body mass index of adults with intellectual disability participating in Special Olympics by world region

BACKGROUND

People with intellectual disability (ID) experience poorer health and have more unmet health needs compared with people without ID, and they are often absent from population health surveillance. The aim of this study was to describe the body mass index (BMI) status of adult Special Olympics participants by world region and gender. Additionally, the general influence of age and gender on overweight/obesity of all participants was explored.

METHOD

A total of 11 643 (7150 male and 4493 female) Special Olympics BMI records were available from the Special Olympics International Health Promotion database. BMI was compared by gender and world region. Logistic regression was used to examine whether age and gender were associated with the likelihood of being overweight/obese (BMI ≥ 25.0).

RESULTS

Overall, 5.5% of the sample was underweight, 36.1% in the normal range, 24.7% overweight and 32.1% obese, and levels of overweight/obesity were very high in North America. Both age and gender were significant predictors of overweight/obesity (odds ratios 1.06 and 0.59, respectively).

CONCLUSIONS

Our findings demonstrate that adult Special Olympics participants have high levels of overweight and obesity; particularly among women and those from North America. It is crucial that those who work with, care for, coach and live with adults with ID who participate in Special Olympics increase efforts to promote healthy weight status.

An miRNA assay for the classification of benign and neoplastic lesions in pancreatic fine-needle aspirates

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Background: Improved diagnosis of pancreatic ductal adenocarcinoma (PDAC) versus benign pancreatic lesions is an urgent clinical need. We previously reported a laboratory-developed test based on the differential expression of two miRNAs, miR-196a and miR-217, with a sensitivity and specificity of 95% in formalin-fixed, paraffin-embedded (FFPE) specimens with ≥60% tumor content. Here, we report the development and validation of an miRNA-based research test optimized for low % tumor specimens and fine needle aspirates (FNA).

Methods: RNA was extracted using methods developed and validated by the Asuragen Services Laboratory from frozen, FFPE or FNA pancreatic specimens. One to three endoscopic ultrasonography-guided FNAs were collected, stored, and shipped in RNARetain, an RNA stabilization solution formulated in 1 mL single-use vials. Expression levels of up to 12 miRNAs were interrogated using TaqMan qRT-PCR assays.

Results: A set of 211 specimens, including 94 PDAC, 96 chronic pancreatitis, and 21 normal, was used to develop a miRNA classifier to discriminate benign and low tumor content PDAC. Training on 95 FFPE specimens showed that expression analysis of miR-196a, -210, and -375 improved by 2- to 3-fold the detection rate of PDAC in specimens with 5-88% tumor. The classifier performance was further verified on 4 independent sets of specimens (n=116): frozen with high tumor content (80-100%), FFPE with high tumor content (60-95%), FFPE with low tumor content (10-60%), and FNA. The signature is now being evaluated in a multisite prospective study using FNAs collected in RNARetain; 110 specimens have been analyzed to date and we will report the relative performance of the 2- and 3-miRNA classifiers.

Conclusions: Benign lesions and PDAC can be accurately classified based on the expression level of a few miRNAs in specimens with 5-100% tumor and in FNA. Testing of preoperative FNAs collected in RNARetain as part of routine clinical evaluation could in the future improve the differential diagnosis of PDAC and potentially reduce the rate of indeterminate or false-negative calls.

[Table: see text]

Relief of the pain of neuromas-in-continuity and scarred median and ulnar nerves in the distal forearm and wrist by neurolysis, wrapping in vascularized forearm fascial flaps and adjunctive procedures

This prospective study reports treatment by neurolysis then wrapping the nerves in vascularized forearm fascia and, when necessary, adjunctive procedures of twelve median and two ulnar nerves in continuity in the distal forearm with neurogenic pain. Preoperatively, all 14 patients had severe pain in at least one of the five modalities of pain analysed. There was complete resolution of all modalities of pain in eight of 14 patients following neurolysis and fascial nerve wrap surgery and two more patients had only mild pain in one or two modalities. After the addition of wrist pinning or arthrodesis alone or in conjunction with selective division of flexor tendons in four patients, there was complete resolution of all modalities of pain in nine of 14 patients. A further three patients had mild pain in three or less modalities and only one patient continued to have severe pain in one modality.