Acquisition and retention of military surgical competencies: a survey of surgeons' experiences in the UK Defence Medical Services

INTRODUCTION

The acquisition and retention of militarily relevant surgical knowledge and skills are vital to enable expert management of combat casualties on operations. Opportunities for skill sustainment have reduced due to the cessation of combat operations in Iraq and Afghanistan and lack of military-relevant trauma in UK civilian practice.

METHODS

A voluntary, anonymous online survey study was sent to all UK Defence Medical Services (DMS) surgical consultants and higher surgical trainees in Trauma and Orthopaedics, Plastic and Reconstructive, and General and Vascular surgical specialties (three largest surgical specialties in the DMS in terms of numbers). The online questionnaire tool included 20 questions using multiple choice and free text to assess respondents' subjective feelings of preparedness for deployment as surgeons for trauma patients.

RESULTS

There were 71 of 108 (66%) responses. Sixty-four (90%) respondents were regular armed forces, and 46 (65%) worked in a Major Trauma Centre (MTC). Thirty-three (47%) had never deployed on operations in a surgical role. Nineteen (27%) felt they had sufficient exposure to penetrating trauma. When asked 'How well do you feel your training and clinical practice prepares you for a surgical deployment?' on a scale of 1-10, trainees scored significantly lower than consultants (6 (IQR 4-7) vs 8 (IQR 7-9), respectively; p<0.001). There was no significant difference in scores between regular and reservists, or between those working at an MTC versus non-MTC. Respondents suggested high-volume trauma training and overseas trauma centre fellowships, simulation, cadaveric and live-tissue training would help their preparedness.

CONCLUSIONS

There was a feeling among a sample of UK DMS consultants and trainees that better preparedness is required for them to deploy confidently as a surgeon for combat casualties. The responses suggest that UK DMS surgical training requires urgent attention if current surgeons are to be ready for their role on deployed operations.

Evaluation of tissue- and plasma-derived tumor mutational burden (TMB) and genomic alterations of interest in CheckMate 848, a study of nivolumab combined with ipilimumab and nivolumab alone in patients with advanced or metastatic solid tumors with high TMB

BACKGROUND

An accumulation of somatic mutations in tumors leads to increased neoantigen levels and antitumor immune response. Tumor mutational burden (TMB) reflects the rate of somatic mutations in the tumor genome, as determined from tumor tissue (tTMB) or blood (bTMB). While high tTMB is a biomarker of immune checkpoint inhibitor (ICI) treatment efficacy, few studies have explored the clinical utility of bTMB, a less invasive alternative for TMB assessment. Establishing the correlation between tTMB and bTMB would provide insight into whether bTMB is a potential substitute for tTMB. We explored the tumor genomes of patients enrolled in CheckMate 848 with measurable TMB. The correlation between tTMB and bTMB, and the factors affecting it, were evaluated.

METHODS

In the phase 2 CheckMate 848 (NCT03668119) study, immuno-oncology-naïve patients with advanced, metastatic, or unresectable solid tumors and tTMB-high or bTMB-high (≥10 mut/Mb) were prospectively randomized 2:1 to receive nivolumab plus ipilimumab or nivolumab monotherapy. Tissue and plasma DNA sequencing was performed using the Foundation Medicine FoundationOne CDx and bTMB Clinical Trial Assays, respectively. tTMB was quantified from coding variants, insertions, and deletions, and bTMB from somatic base substitutions. Correlations between tTMB and bTMB were determined across samples and with respect to maximum somatic allele frequency (MSAF). Assay agreement and variant composition were also evaluated.

RESULTS

A total of 1,438 and 1,720 unique tissue and blood samples, respectively, were obtained from 1,954 patients and included >100 screened disease ontologies, with 1,017 unique pairs of tTMB and bTMB measurements available for assessment. Median tTMB and bTMB were 3.8 and 3.5 mut/Mb, respectively. A significant correlation between tTMB and bTMB (r=0.48, p<0.0001) was observed across all sample pairs, which increased to r=0.54 (p<0.0001) for samples with MSAF≥1%. Assay concordance was highest for samples with MSAF≥10% across multiple disease ontologies and observed for both responders and non-responders to ICI therapy. The variants contributing to tTMB and bTMB were similar.

CONCLUSIONS

We observed that tTMB and bTMB had a statistically significant correlation, particularly for samples with high MSAF, and that this correlation applied across disease ontologies. Further investigation into the clinical utility of bTMB is warranted.

Abstract 5580: Circulating tumor DNA (ctDNA) identifies genomic alterations associated with resistance to Nivolumab in combination with other agents in metastatic castration-resistant prostate cancer from the CheckMate 9KD trial

Introduction: Metastatic castration-resistant prostate cancer (mCRPC) is characterized by an immunosuppressive tumor microenvironment resulting in resistance to single agent immunotherapy, and several combination strategies are being clinically evaluated to address this resistance. CheckMate 9KD (NCT03338790) was a nonrandomized, open-label, multicohort, phase 2 trial of nivolumab combined with rucaparib, docetaxel, or enzalutamide for mCRPC, which showed encouraging clinical activity for the nivolumab plus docetaxel combination. To identify genetic factors potentially associated with response or resistance in this trial, we conducted a retrospective analysis of the tumor genomic alteration landscape utilizing circulating tumor DNA (ctDNA) from plasma samples.

Methods: We performed integrated analyses of sequence and structural alterations identified through comprehensive genomic profiling of cell-free DNA (cfDNA) obtained from plasma at baseline using the GuardantOMNI™ assay (500 genes). The analysis was performed on 253 unique samples across all cohorts for which both clinical and OMNI datasets were available. Variant prevalence in ctDNA was compared to that of matched tumor tissue using the FoundationONE® assay (395 genes). Hazard ratios with corresponding two-sided 95% CI were estimated via unstratified multivariable Cox modeling adjusted by subject age and homologous recombination repair deficiency (HRD) status. Odds ratios with corresponding two-sided 95% CI were estimated via unstratified logistic regression modeling adjusted by subject age and HRD status.

Results: Most patients (239/253; 94.5%) were ctDNA(+), with a substantially higher prevalence of most gene variants detected in cfDNA compared to patient-matched tumor tissue. Mutations in the AR, TERT, DNMT3A, HNF1A, and TP53 genes had the highest frequency. Amplifications in a number of genes detected in ctDNA including the androgen receptor (AR), PI3K/Akt pathway regulators (PIK3CA, PIK3CB, PREX2), and epigenetic regulators (DNMT3A, EZH2, KDM6A), were positively associated with poorer clinical outcomes (rPFS and/or OS) in the nivolumab + docetaxel arm.

Conclusions: This investigation highlights the utility of liquid biopsy for evaluating tumor genomic alterations in late-stage mCRPC trials and provides translational insights into potential resistance mechanisms to inform patient selection and combination strategies for future clinical development.

Acknowledgements: We acknowledge the patients and families, clinical study teams, and investigators who made the CheckMate 9KD study possible, and acknowledge Guardant Health and Foundation Medicine for the collaborative development and validation of the GuardantOMNI™ and FoundationOne®CDx assays, respectively.

Citation Format: Yu Wang, Jun Li, Jonathan Baden, Saurabh Gupta, Justin M. David. Circulating tumor DNA (ctDNA) identifies genomic alterations associated with resistance to Nivolumab in combination with other agents in metastatic castration-resistant prostate cancer from the CheckMate 9KD trial. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5580.

Contrived Materials and a Data Set for the Evaluation of Liquid Biopsy Tests: A Blood Profiling Atlas in Cancer (BLOODPAC) Community Study

The Blood Profiling Atlas in Cancer (BLOODPAC) Consortium is a collaborative effort involving stakeholders from the public, industry, academia, and regulatory agencies focused on developing shared best practices on liquid biopsy. This report describes the results from the JFDI (Just Freaking Do It) study, a BLOODPAC initiative to develop standards on the use of contrived materials mimicking cell-free circulating tumor DNA, to comparatively evaluate clinical laboratory testing procedures. Nine independent laboratories tested the concordance, sensitivity, and specificity of commercially available contrived materials with known variant-allele frequencies (VAFs) ranging from 0.1% to 5.0%. Each participating laboratory utilized its own proprietary evaluation procedures. The results demonstrated high levels of concordance and sensitivity at VAFs of >0.1%, but reduced concordance and sensitivity at a VAF of 0.1%; these findings were similar to those from previous studies, suggesting that commercially available contrived materials can support the evaluation of testing procedures across multiple technologies. Such materials may enable more objective comparisons of results on materials formulated in-house at each center in multicenter trials. A unique goal of the collaborative effort was to develop a data resource, the BLOODPAC Data Commons, now available to the liquid-biopsy community for further study. This resource can be used to support independent evaluations of results, data extension through data integration and new studies, and retrospective evaluation of data collection.

1060 Surgical Currency - the Link Between Skill Fade and Safe Practice

Aim

Surgical currency refers to the operating time required per year before a surgeon's skill fade could negatively affect patient outcomes. Increased surgical experience and volume of operating hours directly improves patient outcomes. There is no clear guidance from the NHS or Defence Medical Services on amount of experience needed to maintain current. This paper highlights the importance of surgical currency, investigates if skill fade occurs faster than knowledge, and looks to ensure surgeons are not deployed beyond the point of currency. It explores methods to prevent skill fade and reintegrate surgeons following absence.

Method

A thorough literature search was performed. Currency protocols across Royal Colleges, healthcare systems and other industries were studied, including systems installed to mitigate skill fade during COVID-19.

Results

An average deployment for a military surgeon will be three months, but pre-deployment training can make this six. The AMRC states an absence over three months affects medical knowledge. Skill fade occurs more rapidly than knowledge, but research remains limited for how long a well-practiced skill is retained. The aviation industry clearly stipulates a pilot's currency, and simulator training is provided following absence. US surgical simulator training proved effective in maintaining skills during the pandemic. Health Education England and Royal College of Surgeons Edinburgh provides return programs for trainees but not consultants.

Conclusions

Careful consideration should be given before extending surgical deployments. Surgical simulation could be used while deployed to maintain currency. Return-to-work programs should be available to consultants. Further research should be done on currency and prevention of skill fade.

Creating Standards for Liquid Biopsies: The BLOODPAC Experience

Since the first Food and Drug Administration (FDA) approval in 2013, liquid biopsy-based platforms have transformed the precision management of patients with advanced cancer. Liquid biopsy holds a demonstrated role in precision medicine that historically focused on targeted therapy selection. Yet, continued innovation in this area is expected to drive growing utility for liquid biopsy-based tests in other areas of clinical need, including minimal (or molecular) residual disease monitoring and early-stage.

Changes in Circulating Tumor DNA Reflect Clinical Benefit Across Multiple Studies of Patients With Non-Small-Cell Lung Cancer Treated With Immune Checkpoint Inhibitors

PURPOSE

As immune checkpoint inhibitors (ICI) become increasingly used in frontline settings, identifying early indicators of response is needed. Recent studies suggest a role for circulating tumor DNA (ctDNA) in monitoring response to ICI, but uncertainty exists in the generalizability of these studies. Here, the role of ctDNA for monitoring response to ICI is assessed through a standardized approach by assessing clinical trial data from five independent studies.

PATIENTS AND METHODS

Patient-level clinical and ctDNA data were pooled and harmonized from 200 patients across five independent clinical trials investigating the treatment of patients with non-small-cell lung cancer with programmed cell death-1 (PD-1)/programmed death ligand-1 (PD-L1)-directed monotherapy or in combination with chemotherapy. CtDNA levels were measured using different ctDNA assays across the studies. Maximum variant allele frequencies were calculated using all somatic tumor-derived variants in each unique patient sample to correlate ctDNA changes with overall survival (OS) and progression-free survival (PFS).

RESULTS

We observed strong associations between reductions in ctDNA levels from on-treatment liquid biopsies with improved OS (OS; hazard ratio, 2.28; 95% CI, 1.62 to 3.20; P < .001) and PFS (PFS; hazard ratio 1.76; 95% CI, 1.31 to 2.36; P < .001). Changes in the maximum variant allele frequencies ctDNA values showed strong association across different outcomes.

CONCLUSION

In this pooled analysis of five independent clinical trials, consistent and robust associations between reductions in ctDNA and outcomes were found across multiple end points assessed in patients with non-small-cell lung cancer treated with an ICI. Additional tumor types, stages, and drug classes should be included in future analyses to further validate this. CtDNA may serve as an important tool in clinical development and an early indicator of treatment benefit.

Abstract 2139: Evaluation of tissue- and plasma-derived tumor mutational burden and genomic alterations of interest from the CheckMate 848 clinical trial

Tumor mutational burden (TMB) derived from tissue biopsies (tTMB) has been associated with clinical efficacy in patients treated with immune checkpoint inhibitors; the clinical utility of TMB derived from blood samples (bTMB) has also been demonstrated but is less widely studied. Little is known about the concordance between tissue- and blood-derived genomic assessments and the factors that contribute to their discordance, underlying the need for further investigation of sequence alteration profiles for successful adoption of noninvasive tumor profiling. We explored the genomic landscape, including concordance between tTMB and bTMB, in samples from patients who were screened for enrollment into CheckMate 848, a prospective, phase 2 study of nivolumab plus ipilimumab and nivolumab monotherapy in patients with advanced or metastatic solid tumors with high TMB (NCT03668119).

Of 1954 screened patients, 212 were randomized, with a cap of 15% per tumor type. Tissue- (FoundationOne® CDx—based Clinical Trial Assay) and blood-based (Foundation Medicine bTMB Clinical Trial Assay) genomic data were utilized for analysis of genomic variants, tTMB, and bTMB. In total, 1438 unique tissue and 1720 unique plasma samples were analyzed during trial screening (June 2021 database lock). Of over 100 screened disease ontologies (taken from the tissue diagnosis), pancreatic (9.7%), breast (8.8%), and ovarian (6.1%) cancers, as well as cholangiocarcinoma (5.2%), were the most common. A total of 1141 tissue and 1573 plasma samples passed established quality control criteria, resulting in ascertainment levels of 79.3% for tTMB and 91.5% for bTMB. A correlation between tTMB and bTMB scores was identified across 1017 tissue and plasma sample pairs (Spearman’s r, 0.48; P &lt; 0.0001). Median (range) tTMB and bTMB were 3.8 (0—452.6) and 3.5 (0—1027.5) mutations per megabase (mut/Mb), respectively. High microsatellite instability (MSI) was detected in 25 (2.5%) MSI-evaluable tissue samples; in these patients, median tTMB was 25.2 mut/Mb. At the prespecified cutoff of 10 mut/Mb, 15.8% and 20.7% of samples had high tTMB and bTMB, respectively; the positive (PPA), negative, and overall percentage agreements between assays were 60%, 88%, and 84%, respectively. TMB correlation (Spearman’s r, 0.54; P &lt; 0.0001) and PPA (66%) were improved among 806 (79.3%) sample pairs with plasma maximum somatic allele frequency ≥ 1%.

In CheckMate 848, data from paired biopsies revealed the complementary nature of TMB assessments from tissue and blood, suggesting that both approaches may have the potential to identify high mutational burden in samples obtained from patients with advanced solid tumors. Further interrogation of the biological and analytical factors affecting tumor- and blood-derived genomic profiling is warranted to support their implementation in clinical settings.

Citation Format: Jie He, Natallia Kalinava, Parul Doshi, Jie Ma, Dean C. Pavlick, Lee A. Albacker, Hanna Tukachinsky, Gina Fusaro, Geoffrey R. Oxnard, George Green, David Fabrizio, Jonathan Baden. Evaluation of tissue- and plasma-derived tumor mutational burden and genomic alterations of interest from the CheckMate 848 clinical trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2139.

Abstract CT022: CheckMate 848: A randomized, open-label, phase 2 study of nivolumab in combination with ipilimumab or nivolumab monotherapy in patients with advanced or metastatic solid tumors of high tumor mutational burden

High tumor mutational burden assessed in tissue biopsies (tTMB-H) or blood (bTMB-H) is associated with clinical efficacy in patients treated with immunotherapies. CheckMate 848 (NCT03668119) is a prospective phase 2 study of nivolumab (NIVO) with or without ipilimumab (IPI) in patients with advanced or metastatic solid tumors that are tTMB-H or bTMB-H (≥ 10 mutations/megabase) who were immunotherapy-naive and refractory to standard local therapies.

The primary endpoint was objective response rate (ORR) in patients with tTMB-H or bTMB-H, assessed by FoundationOne® CDx-based and Clinical Trial Assays (Foundation Medicine), respectively. The study was not powered to compare NIVO + IPI vs NIVO. We present the interim and final analyses for the tTMB-H and bTMB-H cohorts, respectively (≥ 12 months follow-up, database lock June 2021).

Of 1954 screened patients, 212 were randomized 2:1 to NIVO 240 mg Q2W + IPI 1 mg/kg Q6W or NIVO 480 mg Q4W for ≤ 24 months, and 201 (135 tTMB-H; 147 bTMB-H) were refractory to standard therapies. Of &gt; 40 tumor types, colorectal (10.8%), small-cell lung (7.5%), breast (7.1%), and uterine (7.1%) were the most common. ORR and survival outcomes with NIVO + IPI were improved in patients with tTMB-H. The responses were independent of bTMB-H status in the tTMB-H cohort but improved with tTMB-H status in the bTMB-H cohort (Table). The safety profile of NIVO + IPI was manageable, and clinical outcomes with NIVO were comparable with previous studies. The impact of TMB cutoff, PD-L1 expression, and microsatellite instability were explored.

In conclusion, NIVO + IPI demonstrated clinical efficacy with a manageable safety profile in patients with advanced or metastatic solid tumors that are tTMB-H or bTMB-H and refractory to standard therapies, with increased efficacy observed in patients with tTMB-H.

NIVO + IPI tTMB-H cohort bTMB-H cohorta Patients, n (%)b,c 68 (32.1) 80 (37.7) Number of prior treatments, median (range) 2 (0–7) 2 (1–9) ORR, n (%)c, 95% CI 24 (35.3), 24.1–47.8 18 (22.5), 13.9–33.2 ORR in patients with bTMB-H by tTMBc: &lt; 10 mut/Mb (n = 31), n (%), 95% CI NA 3 (9.7), 2.0–25.8 ≥ 10 mut/Mb (n = 39), n (%), 95% CI NA 13 (33.3), 19.1–50.2 ≥ 10 to &lt; 16 mut/Mb (n = 18), n (%), 95% CI NA 3 (16.7), 3.6–41.4 ≥ 16 mut/Mb (n = 21), n (%), 95% CI NA 10 (47.6), 25.7–70.2 ORR in patients with tTMB-H by bTMBc: &lt; 10 mut/Mb (n = 20), n (%), 95% CI 7 (35.0), 15.4–59.2 NA ≥ 10 mut/Mb (n = 43), n (%), 95% CI 16 (37.2), 23.0–53.3 NA ≥ 10 to &lt; 16 mut/Mb (n = 12), n (%), 95% CI 3 (25.0), 5.5–57.2 NA ≥ 16 mut/Mb (n = 31), n (%), 95% CI 13 (41.9), 24.5–60.9 NA Percentage of responders (≥ 9 months) (95% CI) 91 (68–98) 88 (61–97) Median PFS, months (95% CI)c 4.1 (2.8–11.3) 2.8 (2.3–3.0) Median OS, months (95% CI)c 14.5 (7.7–NE) 8.5 (5.8–10.5) aThe bTMB cohort was randomized prior to December 20, 2019. bOut of 212 randomized patients; data presented in this table are from patients who were refractory to standard therapies. cMinimum follow-up 12 months. bTMB, blood tumor mutational burden; NA, not applicable; NE, not evaluable; PFS, progression-free survival; OS, overall survival; tTMB, tissue tumor mutational burden.

Citation Format: Michael Schenker, Mauricio Burotto, Martin Richardet, Tudor Ciuleanu, Anthony Goncalves, Neeltje Steeghs, Patrick Schöffski, Paolo A. Ascierto, Michele Maio, Iwona Lugowska, Lorena Lupinacci, Alexandra Leary, Jean-Pierre Delord, Julieta Grasselli, David S. Tan, Jennifer E. Friedmann, Jacqueline Vuky, Marina Tschaika, Ruta Slepetis, Georgia D. Kollia, Misena Pacius, Ning Huang, Parul Doshi, Jonathan Baden, Massimo Di Nicola. CheckMate 848: A randomized, open-label, phase 2 study of nivolumab in combination with ipilimumab or nivolumab monotherapy in patients with advanced or metastatic solid tumors of high tumor mutational burden [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT022.

Aligning tumor mutational burden (TMB) quantification across diagnostic platforms: phase II of the Friends of Cancer Research TMB Harmonization Project

BACKGROUND

Tumor mutational burden (TMB) measurements aid in identifying patients who are likely to benefit from immunotherapy; however, there is empirical variability across panel assays and factors contributing to this variability have not been comprehensively investigated. Identifying sources of variability can help facilitate comparability across different panel assays, which may aid in broader adoption of panel assays and development of clinical applications.

MATERIALS AND METHODS

Twenty-nine tumor samples and 10 human-derived cell lines were processed and distributed to 16 laboratories; each used their own bioinformatics pipelines to calculate TMB and compare to whole exome results. Additionally, theoretical positive percent agreement (PPA) and negative percent agreement (NPA) of TMB were estimated. The impact of filtering pathogenic and germline variants on TMB estimates was assessed. Calibration curves specific to each panel assay were developed to facilitate translation of panel TMB values to whole exome sequencing (WES) TMB values.

RESULTS

Panel sizes >667 Kb are necessary to maintain adequate PPA and NPA for calling TMB high versus TMB low across the range of cut-offs used in practice. Failure to filter out pathogenic variants when estimating panel TMB resulted in overestimating TMB relative to WES for all assays. Filtering out potential germline variants at >0% population minor allele frequency resulted in the strongest correlation to WES TMB. Application of a calibration approach derived from The Cancer Genome Atlas data, tailored to each panel assay, reduced the spread of panel TMB values around the WES TMB as reflected in lower root mean squared error (RMSE) for 26/29 (90%) of the clinical samples.

CONCLUSIONS

Estimation of TMB varies across different panels, with panel size, gene content, and bioinformatics pipelines contributing to empirical variability. Statistical calibration can achieve more consistent results across panels and allows for comparison of TMB values across various panel assays. To promote reproducibility and comparability across assays, a software tool was developed and made publicly available.

Forklift-related lower limb injuries: a retrospective case series study with patient-reported outcome measures (PROMs)

AIM

Forklift trucks can cause serious lower limb trauma with long-lasting sequelae to patients. The aim of this study was to analyse a case series of patients with forklift-related injuries over 7 years at a level 1 major trauma centre in the UK and present their patient-reported outcome measures (PROMs) with long-term follow-up. To the best of the authors' knowledge, this is the largest case series study in the UK describing forklift injuries.

METHODS

Retrospective case note analysis of 19 patients over 7 years. Data including demographics, injury mechanism, pattern of injury, management, length of hospital stay, number of operations and complications were extracted from the notes. We used 'Enneking score' as a validated tool for PROMs.

RESULTS

Seventeen men and two women with mean age of 47 years; 20% had bilateral injuries and 34% had multi-level fractures. The mean number of theatre sessions was 5.21, while the mean length of hospital stay was 30.10 days. There was one mortality. Twelve patients (63%) required reconstruction with free tissue transfer, with one flap failure. The mean long-term Enneking percentage score was 57.33%. The mean Enneking score for patients in this study is lower than our institute's score for Gustilo 3B, highlighting the gravity of these injuries.

CONCLUSION

Forklifts can cause grave injuries with massive energy transfer. This study highlights the seriousness of those injuries, thus guiding patient counselling and optimising planning of management.

Establishing guidelines to harmonize tumor mutational burden (TMB): in silico assessment of variation in TMB quantification across diagnostic platforms: phase I of the Friends of Cancer Research TMB Harmonization Project

Background

Tumor mutational burden (TMB), defined as the number of somatic mutations per megabase of interrogated genomic sequence, demonstrates predictive biomarker potential for the identification of patients with cancer most likely to respond to immune checkpoint inhibitors. TMB is optimally calculated by whole exome sequencing (WES), but next-generation sequencing targeted panels provide TMB estimates in a time-effective and cost-effective manner. However, differences in panel size and gene coverage, in addition to the underlying bioinformatics pipelines, are known drivers of variability in TMB estimates across laboratories. By directly comparing panel-based TMB estimates from participating laboratories, this study aims to characterize the theoretical variability of panel-based TMB estimates, and provides guidelines on TMB reporting, analytic validation requirements and reference standard alignment in order to maintain consistency of TMB estimation across platforms.

Methods

Eleven laboratories used WES data from The Cancer Genome Atlas Multi-Center Mutation calling in Multiple Cancers (MC3) samples and calculated TMB from the subset of the exome restricted to the genes covered by their targeted panel using their own bioinformatics pipeline (panel TMB). A reference TMB value was calculated from the entire exome using a uniform bioinformatics pipeline all members agreed on (WES TMB). Linear regression analyses were performed to investigate the relationship between WES and panel TMB for all 32 cancer types combined and separately. Variability in panel TMB values at various WES TMB values was also quantified using 95% prediction limits.

Results

Study results demonstrated that variability within and between panel TMB values increases as the WES TMB values increase. For each panel, prediction limits based on linear regression analyses that modeled panel TMB as a function of WES TMB were calculated and found to approximately capture the intended 95% of observed panel TMB values. Certain cancer types, such as uterine, bladder and colon cancers exhibited greater variability in panel TMB values, compared with lung and head and neck cancers.

Conclusions

Increasing uptake of TMB as a predictive biomarker in the clinic creates an urgent need to bring stakeholders together to agree on the harmonization of key aspects of panel-based TMB estimation, such as the standardization of TMB reporting, standardization of analytical validation studies and the alignment of panel-based TMB values with a reference standard. These harmonization efforts should improve consistency and reliability of panel TMB estimates and aid in clinical decision-making.

Planning for UK terror attacks: Analysis of blast and ballistic injuries

Terrorist attacks have become more acute, less predictable and frequently involve use of explosives and gunfire to inflict mass casualty to civilians. Resource demand has been reported in Role 3 Medical Facilities but the continued resource required to manage blast and ballistic injuries has not been quantified. This study aimed to assess the resource required for blast and ballistic injuries at the United Kingdom's Role 4 Medical Facility. Military patients admitted to the Queen Elizabeth Hospital (Role 4 Medical Facility) from Afghanistan with blast or ballistic injuries during the 2012 calendar year were retrospectively reviewed. Injury pattern, theatre resource, length of stay and cost analysis were performed. This study included 99 blast and 53 gunshot wound (GSW) patients. Blast patients were more likely to suffer polytrauma than GSW (53% vs 23%), underwent more surgical procedures and utilized double the theatre time. Blast injury patients had a longer length of stay in hospital. The average cost per patient for blast patients was double that of the GSW injury cohort. The Queen Elizabeth experience represents a continuous flow of severely injured military casualties whilst managing concurrent civilian trauma over a long period. This workload has encouraged systematic advancements in managing high numbers of injured patients from point of wounding to rehabilitation. Distribution of resource, theatre planning and multi-disciplinary team working are critical in effectively managing Major Incidents such as terror attacks. Drawing on previous Role 4 Medical Facility experience can aid UK hospitals in terms of strategy and resource distribution.

Nivolumab and Ipilimumab as Maintenance Therapy in Extensive-Disease Small-Cell Lung Cancer: CheckMate 451

In extensive-disease small-cell lung cancer (ED-SCLC), response rates to first-line platinum-based chemotherapy are robust, but responses lack durability. CheckMate 451, a double-blind phase III trial, evaluated nivolumab plus ipilimumab and nivolumab monotherapy as maintenance therapy following first-line chemotherapy for ED-SCLC.

From chaos to a new norm: The Birmingham experience of restructuring the largest plastics department in the UK in response to the COVID-19 pandemic

The coronavirus disease 2019 (COVID-19) pandemic presented unprecedented challenges for healthcare systems worldwide. The Queen Elizabeth Hospital, Birmingham, has one of the largest burns, hands and plastics department in the UK, totalling 83 doctors. Our response to the COVID-19 response was uniquely far reaching, with our department being given responsibility of an entire 36 bed medical COVID-19 ward in addition to our commitment to specialty-specific work, and saw half of our work force re-deployed to Intensive Treatment Unit (ITU). Our aim was to exploit the high calibre of doctors found in plastic surgery, and to demonstrate, we were able to support the COVID-19 effort beyond our normal scope of practice.

In order to achieve this aim, the department underwent significant structural and leadership changes. Factors considered included: rota and shift pattern changes to implement depth and resilience to sudden fluctuations in staffing levels; a preparatory phase for focussed upskilling and relevant training packages to be delivered; managing the COVID-19 ward cover and ITU deployment; adjustments to our front of house and elective specialty-specific service, including developing alternative and streamlined patient pathways; mitigating the effects on plastic surgical training during the pandemic; the importance of communications for patient care and physician wellbeing; and leadership techniques and styles we considered important.

By sharing our experience during this pandemic, we hope to reflect on and share lessons learned, as well as to demonstrate that it is possible to rapidly mobilise and retrain plastic surgeons at all levels to contribute safely and productively beyond a specialty-specific scope of care.

Skill sets required for the management of military head, face and neck trauma: a multidisciplinary consensus statement

Introduction

The evolution of medical practice is resulting in increasing subspecialisation, with head, face and neck (HFN) trauma in a civilian environment usually managed by a combination of surgical specialties working as a team. However, the full combination of HFN specialties commonly available in the NHS may not be available in future UK military-led operations, necessitating the identification of a group of skill sets that could be delivered by one or more deployed surgeons.

Method

A systematic review was undertaken to identify those surgical procedures performed to treat acute military head, face, neck and eye trauma. A multidisciplinary consensus group was convened following this with military HFN trauma expertise to define those procedures commonly required to conduct deployed, in-theatre HFN surgical combat trauma management.

Results

Head, face, neck and eye damage control surgical procedures were identified as comprising surgical cricothyroidotomy, cervico-facial haemorrhage control and decompression of orbital haemorrhage through lateral canthotomy. Acute in-theatre surgical skills required within 24 hours consist of wound debridement, surgical tracheostomy, decompressive craniectomy, intracranial pressure monitor placement, temporary facial fracture stabilisation for airway management or haemorrhage control and primary globe repair. Delayed in-theatre procedures required within 5 days prior to predicted evacuation encompass facial fracture fixation, delayed lateral canthotomy, evisceration, enucleation and eyelid repair.

Conclusions

The identification of those skill sets required for deployment is in keeping with the General Medical Council’s current drive towards credentialing consultants, by which a consultant surgeon’s capabilities in particular practice areas would be defined. Limited opportunities currently exist for trainees and consultants to gain experience in the management of traumatic head, face, neck and eye injuries seen in a kinetic combat environment. Predeployment training requires that the surgical techniques described in this paper are covered and should form the curriculum of future military-specific surgical fellowships. Relevant continued professional development will be necessary to maintain required clinical competency.

Predicting prostate biopsy result in men with prostate specific antigen 2.0 to 10.0 ng/ml using an investigational prostate cancer methylation assay

PURPOSE

The inadequacies of prostate specific antigen testing have created a need for novel markers for prostate cancer screening. The investigational ProCaM™ prostate cancer methylation assay detects aberrant methylation of DNA in cells associated with prostate cancer. We describe a large, prospective, multicenter study done to verify the performance of this assay.

MATERIALS AND METHODS

The assay is designed to detect epigenetic modifications in the 3 markers GSTP1, RARβ2 and APC, which are indicative of prostate cancer. A total of 232 men with cancer and 283 without cancer from 18 clinical sites were evaluated by trained operators at central testing laboratories. Study inclusion criteria were age 40 to 75 years, total prostate specific antigen between 2.0 and 10.0 ng/ml, and a digital rectal examination result. All participants signed an informed consent form and underwent transrectal ultrasound guided needle biopsy with 10 or more cores.

RESULTS

Assay sensitivity was 60%, specificity was 80% and the informative rate was 97%. Assay predictive accuracy was higher than that of age, digital rectal examination, family history, prostate specific antigen, prior negative biopsy and prostate volume (AUC 0.73 vs 0.52 to 0.66, p <0.038). Risk factors plus the assay improved overall predictive power (AUC 0.79, p = 0.001). A man with a positive prostate cancer methylation result was 7.7 times more likely to have high grade cancer.

CONCLUSIONS

The prostate cancer methylation assay correlated with positive biopsy and with Gleason score. This assay has the potential to add value to the biopsy decision making process by improving current prostate cancer screening algorithms to more accurately identify men with prostate cancer.

Multicenter evaluation of an investigational prostate cancer methylation assay

PURPOSE

Prostate specific antigen tests have low specificity, which frequently results in unnecessary biopsy and typically limits screening to patients with prostate specific antigen greater than 4.0 ng/ml. We evaluated an investigational prostate cancer methylation specific polymerase chain reaction assay that detects aberrant methylation in 3 markers (GSTP1, RARbeta2 and APC) that indicate the presence of prostate cancer.

MATERIALS AND METHODS

The assay was evaluated in 337 post-digital rectal examination urine samples (178 cancer and 159 noncancer) collected prospectively at a total of 9 clinical sites. Samples were processed wholly or after division into equal portions. Subject prostate specific antigen was 2.0 to 10.0 ng/ml. All subjects underwent transrectal ultrasound guided needle biopsy with 6 or greater cores sampled. Detection of 1 or greater markers indicated positivity.

RESULTS

Methylation specific polymerase chain reaction assay performance was better in whole than in divided urine cohorts (p = 0.035). Assay AUC was 0.72 in the whole urine cohort and 0.67 in the combined population. These values were higher than those of prostate specific antigen alone using 4.0 ng/ml as the cutoff (p = 0.00 and 0.01, respectively). Moreover, the assay together with the Prostate Cancer Prevention Trial risk calculator or a standard nomogram significantly improved AUC in the whole urine cohort and the combined population vs predictive algorithms alone (p <0.05). Assay positive predictive value was 54% in whole urine cohort with prostate specific antigen 2.0 to 4.0 ng/ml and negative predictive value was 87% with prostate specific antigen 4.1 to 10.0 ng/ml. Assay positive predictive value was higher in subjects with all 3 methylation markers positive.

CONCLUSIONS

These data demonstrate that this investigational assay used in conjunction with current screening algorithms may potentially add value to the biopsy decision making process.

Informative rate and reproducibility of the investigational GeneSearch ProCaM assay in a multicenter laboratory setting

e22038

Background: PSA tests have low specificity, which frequently results in unnecessary biopsy and typically limits screening to patients with PSA values >4.0 ng/mL. The investigational ProCaM assay detects CpG island methylation within the promoter regions of three markers (GSTP1, RARß2, and APC) that are indicative of the presence of prostate cancer. The objective of this research study was to assess assay testing reproducibility and lot-to-lot variability. Methods: Assay reproducibility: 8 operators from 4 external clinical laboratories tested a panel comprised of a negative panel member (NM2C5 cells) for the internal control (ß-Actin), a high positive and low positive panel members (LNCaP cells) for all 3 markers and ß-Actin. Variability of assay results based on marker cycle threshold (Ct) values was determined. Lot variability: 3 unique lots of the ProCaM Test Kit were evaluated on DNA extracted from 169 post-DRE urine samples to show reproducibility across kit lots. Urine samples were collected from consenting subjects that were scheduled for prostate biopsy and tested by 3 operators at the same facility. Results: Assay reproducibility: The informative rate was 98% (766 valid results of 782 total tests). The overall intersite %CV and SD values for Cts were = 9.2% and 1.49%, respectively. The percent agreement with qualitative (positive/negative) outcome for High, Low, and Negative panel members was = 98% for GSTP1, RARß2, APC, and ß-Actin. Lot variability: Of the 169 biopsy results a histology positivity rate of 39% (66/169) was shown. Urine sample results for these samples showed that the areas under the curve for the 3 unique ProCaM Test Kit lots were equivalent (0.72, 0.74, 0.75, p > 0.263). Using the result categories of negative and positive with identical cutoffs for GSTP1, RARß2, APC for samples with >5 ssDNA copies 98% concordance was observed for all 3 lots evaluated. Conclusions: The investigational assay produces a qualitative result without the requirement for normalization or sample dilution and requires only one reaction per patient sample. Current results demonstrate that the assay has a high informative test rate and that results are reproducible across sites, operators runs, and kit lots.

[Table: see text]

Development of a multiplexed urine assay for prostate cancer diagnosis

BACKGROUND

Several studies have demonstrated the value of DNA methylation in urine-based assays for prostate cancer diagnosis. However, a multicenter validation with a clinical prototype has not been published.

METHODS

We developed a multiplexed, quantitative methylation-specific polymerase chain reaction (MSP) assay consisting of 3 methylation markers, GSTP1, RARB, and APC, and an endogenous control, ACTB, in a closed-tube, homogeneous assay format. We tested this format with urine samples collected after digital rectal examination from 234 patients with prostate-specific antigen (PSA) concentrations > or =2.5 microg/L in 2 independent patient cohorts from 9 clinical sites.

RESULTS

In the first cohort of 121 patients, we demonstrated 55% sensitivity and 80% specificity, with area under the curve (AUC) 0.69. In the second independent cohort of 113 patients, we found a comparable sensitivity of 53% and specificity of 76% (AUC 0.65). In the first cohort, as well as in a combined cohort, the MSP assay in conjunction with total PSA, digital rectal examination status, and age improved the AUC without MSP, although the difference was not statistically significant. Importantly, the GSTP1 cycle threshold value demonstrated a good correlation (R = 0.84) with the number of cores found to contain prostate cancer or premalignant lesions on biopsy. Moreover, samples that exhibited methylation for either GSTP1 or RARB typically contained higher tumor volumes at prostatectomy than those samples that did not exhibit methylation.

CONCLUSIONS

These data confirm and extend previously reported studies and demonstrate the performance of a clinical prototype assay that should aid urologists in identifying men who should undergo biopsy.

Gene profiling of tumor tissue in the diagnosis of patients with carcinoma of unknown primary site (CUP): Evaluation of the Veridex 10-gene molecular assay

21109

Background: Standard treatment for most patients with CUP involves empiric chemotherapy. Since specific treatment now exists for most types of advanced carcinoma, precise identification of the primary site could lead to improved therapy. Veridex developed an optimized set of 10 gene markers, for a qRTPCR assay to identify tissue of origin of metastatic carcinoma in formalin-fixed, paraffin-embedded (FFPE) tissue samples (J Mol Diagn 8:320, 2006). The assay includes markers for 6 primary sites: lung, pancreas, colon, breast, ovary, and prostate. In this retrospective study, we evaluated the Veridex assay in patients with CUP. Methods: We obtained FFPE tissue from diagnostic biopsies on 69 CUP patients previously enrolled in empiric chemotherapy studies. The Veridex assay was performed as previously described. Assay results were correlated with clinical features, pathologic features, and response to treatment. Results: The Veridex assay yielded provisional diagnoses in 42 of 69 patients (61%): lung (15), pancreas (11), colon (12 ), ovary (4), breast (0), and prostate, (0 ). Most patients with diagnoses of lung and pancreas cancer had clinical and pathologic features compatible with these diagnoses; response rates to empiric chemotherapy (usually taxane/platinum-based) in patients with these diagnoses were 29% and 9%, respectively. The 12 patients with colon cancer diagnoses had predominantly intra-abdominal metastases (liver, peritoneum); response rate to therapy (usually taxane/platinum- based) was low (8%). The 4 patients with ovarian cancer had atypical clinical and pathologic features, and only 1 of 4 had PR to first-line taxane/platinum therapy. Conclusions: In this retrospective study, the Veridex 10-gene molecular assay was feasible and provided provisional diagnoses in a majority of patients with CUP. The diagnoses made using this assay (except ovarian cancer) were compatible with clinicopathologic features. The efficacy of cancer-specific treatment in patients diagnosed by this assay will be evaluated in prospective studies.

No significant financial relationships to disclose.

Prospective study of a 10-gene molecular assay to predict tissue of origin in patients with carcinoma of unknown primary (CUP)

21096

Background: Carcinoma of unknown primary (CUP) where metastatic disease presents without an identifiable primary represents ∼ 3–5% of all cancers. Identifying the origin of the primary tumor in CUP pts can facilitate rational choice of therapeutic regimens. Veridex developed an optimized set of 10 gene markers for a quantitative reverse transcriptase polymerase chain reaction (qRTPCR) assay, and demonstrated high accuracy in predicting the tissue of origin with formalin-fixed, paraffin-embedded (FFPE) metastatic carcinoma samples (J Mol Diagn 2006, 8: 320–9). In this study, the 10-gene assay was prospectively evaluated in CUP pts. Methods: We collected FFPE biopsy tissue specimens from consenting CUP pts at MD Anderson. Eligibile pts met our definition for CUP with adenocarcinoma or poorly differentiated carcinoma. Samples were obtained prior to treatment. 51 pts have been enrolled so far and 11 were ineligible [insufficient samples].Of the 40 pts, qRTPCR assay has been performed on 33 pts. Data on 27/33 is available. A statistical model was used to determine the probability that the metastatic carcinoma tissue assayed originated from 1 of the following 7 categories: lung, pancreas, colon, breast, prostate, ovarian, and other. Subsequently, prediction of the primary by qRTPCR was independently compared with metastatic pattern spread, tumor pathological features, and results of clinical and pathology diagnostic workups. Results: Assay results on 27 prospectively collected CUP patient biopsy specimens are available. In total, CUP tissue of origin prediction by the assay correlated with clinical and pathological assessment in 21 out of 27 evaluated pts (78 %). The most common cancer type predicted by the assay was colon cancer, which correlated with predominantly intra-abdominal metastatic spread in this pt cohort. Conclusions: This prospective study demonstrated the feasibility of conducting gene analysis to predict metastatic carcinoma tissue of origin in FFPE tissue specimens derived from CUP patients. Overall distribution of various primary cancer types as predicted by the assay was consistent with the historical distribution reported for CUP. Assay prediction was concordant with clinical and pathological assessment in 78 % CUP pts.

No significant financial relationships to disclose.

A quantitative reverse transcriptase-polymerase chain reaction assay to identify metastatic carcinoma tissue of origin

Identifying the primary site in patients with metastatic carcinoma of unknown primary origin can enable more specific therapeutic regimens and may prolong survival. Twenty-three putative tissue-specific markers for lung, colon, pancreatic, breast, prostate, and ovarian carcinomas were nominated by querying a gene expression profile database and by performing a literature search. Ten of these marker candidates were then selected based on validation by reverse transcriptase-polymerase chain reaction (RT-PCR) on 205 formalin-fixed, paraffin-embedded metastatic carcinoma specimens originating from these six and from other cancer types. Next, we optimized the RNA isolation and quantitative RT-PCR methods for these 10 markers and applied the quantitative RT-PCR assay to a set of 260 metastatic tumors. We then built a gene-based algorithm that predicted the tissue of origin of metastatic carcinomas with an overall leave-one-out cross-validation accuracy of 78%. Lastly, our assay demonstrated an accuracy of 76% when tested on an independent set of 48 metastatic samples, 37 of which were either a known primary or initially presented as carcinoma of unknown primary but were subsequently resolved.

A quantitative reverse transcriptase polymerase chain reaction assay to identify metastatic carcinoma tissue of origin

20024

Background: Carcinoma of unknown primary (CUP) wherein metastatic disease presents without an identifiable primary tumor site represents approximately 3–5% of all cancers. Identifying the origin of the primary tumor in patients with CUP can enable rational choice of therapeutic regimens. We developed an optimized set of ten gene markers for a quantitative reverse transcriptase polymerase chain reaction (qRTPCR) assay, and demonstrated high accuracy in predicting the tissue of origin when used on with formalin-fixed, paraffin-embedded (FFPE) metastatic carcinoma samples. Methods: Twenty-three putative tissue-specific markers for lung, colon, pancreas, breast, prostate and ovarian carcinomas were nominated by querying a gene expression profile database and by performing a literature search. Ten of these marker candidates were then selected based on validation by qRTPCR on 205 FFPE metastatic carcinomas of known tissue origin. Next, we optimized the RNA isolation and qRTPCR methods for these ten markers, and tested the qRTPCR assay on two sets of FFPE metastatic tumors. Results: We applied the 10-gene qRTPCR assay to a set of 260 metastatic tumors of known origin, generating an overall accuracy of 78%. Furthermore we tested an independent set of 48 metastatic samples, including thirty-seven samples where either the tissue of origin was known or which initially presented as CUP but were subsequently resolved. In these 48 samples, our assay demonstrated an accuracy of 76%. Conclusions: Our results suggested that optimized ten-gene markers qRTPCR assay reliably predicts tissue of origin of metastatic carcinomas in FFPE tissues. Such assay can significantly improve the rate of tissue of origin identification for carcinoma of unknown primary.

[Table: see text]

Richter's syndrome

A 56-year-old man with chronic lymphocytic leukemia who developed Richter's syndrome is described. The criteria for diagnosis are given and the histology is discussed. We agree that Richter's syndrome represents a peculiar complication of chronic lymphocytic leukemia and not a separate disease entity. As such, Richter's syndrome must be known and recognized by those evaluating patients with lymphadenopathy whose basic diagnosis may be confused with Hodgkin's disease or "histiocytic" lymphoma.