Evaluation of new haematology analyser, XN-31, for malaria detection in blood donors: A single-centre study from India

BACKGROUND AND OBJECTIVES

Malaria continues to be a significant public health concern in India, with several regions experiencing endemicity and sporadic outbreaks. The prevalence of malaria in blood donors, in India, varies between 0.02% and 0.07%. Common techniques to screen for malaria, in blood donors and patients, include microscopic smear examination and rapid diagnostic tests (RDTs) based on antigen detection. The aim of this study was to evaluate a new fully automated analyser, XN-31, for malaria detection, as compared with current practice of using RDT.

MATERIALS AND METHODS

Cross-sectional analytical study was conducted to evaluate clinical sensitivity and specificity of new automated analyser XN-31 among blood donors' samples and clinical samples (patients with suspicion of malaria) from outpatient clinic collected over between July 2021 and October 2022. No additional sample was drawn from blood donor or patient. All blood donors and patients' samples were processed by malaria rapid diagnostic test, thick-smear microscopy (MIC) and the haematology analyser XN-31. Any donor blood unit incriminated for malaria was discarded. Laboratory diagnosis using MIC was considered the 'gold standard' in the present study. Clinical sensitivity and specificity of XN-31 were compared with the gold standard.

RESULTS

Fife thousand and five donor samples and 82 diagnostic samples were evaluated. While the clinical sensitivity and specificity for donor samples were 100%, they were 96.3% and 100% for diagnostic samples.

CONCLUSION

Automated haematology analysers represent a promising solution, as they can deliver speedy and sensitive donor malaria screening assessments. This method also has the potential to be used for pre-transfusion malaria screening along with haemoglobin estimation.

Perceived Gaps in Academic Training and Expectations From Refresher Training in Primary Care Nurses at an Urban Metropolis in Northern India: A Qualitative Study

Background Nursing professionals, comprising the largest workforce engaged in the primary healthcare system, play a pivotal role in addressing population health needs. However, gaps in the training of nurses and midwives in lower-middle-income countries may undermine their performance and necessary skill development for fulfilling key population health needs. Substantial challenges exist in improving the regular curricular and refresher training of diplomate nurses and midwives working in primary care facilities and supporting both clinical care and health promotion functions. The study objective was to conduct a gap analysis in the present nursing curriculum and training profile of general duty midwives working in urban primary health facilities and understand their expectations and preferences from the planned refresher training course.  Methods We conducted a qualitative explorative study among General Nursing midwives (GNMs) working in urban primary health facilities in the Gurugram district of Haryana, India to conduct a gap analysis in their present curriculum and training preferences.  Results A total of 17 nurses with a mean (SD) age of 33.52 (4.75) years and an average nursing work experience of 5.35 (0.56) years were interviewed in-depth. Lack of practical applicability, complex study material, inexperienced tutors, and weak English language comprehension were key barriers in the existing nursing curriculum. The nurses expressed willingness to participate in refresher training with varied expectations, although there existed a distinct preference for short, flexible, and blended online-offline modes of training.  Conclusions Strengthening GNM nursing education should be prioritized in Indian health settings with the focus on improving student comprehension through vernacular instruction when feasible, and capacity building of tutors, with avenues for continued training and education. There is also a need for strengthening the curriculum related to key emergent public health challenges related to non-communicable diseases and mental health, as also skills for client and patient counseling and communication.

Value of new advanced hematological parameters in early prediction of severity of COVID-19

INTRODUCTION

COVID-19 usually presents with upper respiratory tract infection in varying severity which can lead to sepsis. Early prediction of sepsis may reduce mortality by timely interventions. The intended purpose of this study was to determine whether the advanced parameters like the extended inflammation parameters (EIPs) can predict prognosis and early progression to sepsis as a sequel of COVID-19 infection and can be used as a screening profile. Also, to evaluate the Intensive Care Infection Score (ICIS) and the COVID-19 prognostic score and validate the scores for our population.

METHODS

Prospective observational study of 50 reverse transcription- polymerase chain reaction (RT-PCR) proven admitted COVID-19 patients. The data assessed included complete blood counts (CBC) with EIP measurements, from Day 1 of admission to Day 10. The following groups were studied: noncritical (NC) and critical illness (CI) in COVID-19 positive cases, COVID negative sepsis and nonsepsis cases, and healthy volunteers for reference range.

RESULTS

The parameters that showed statistically significant higher mean in CI group compared to the NC group are reactive lymphocyte number and percentage (RE-LYMPH#, RE-LYMPH%), antibody synthesizing lymphocyte number and percentage (AS-LYMPH#, AS-LYMPH%), Reactive monocyte count and percentage (RE-MONO#, RE-MONO%/M), ICIS, COVID-19 prognostic score (p-value <0.05). The AUC confirmed the diagnostic accuracy of all these parameters. From the multivariate logistic regression, the significant risk factor was RE-LYMPH# with cut-off >0.10 (p value: 0.011).

CONCLUSION

The new EIP parameters, RE-MONO#, RE-MONO%/M, ICIS score and COVID-19 prognostic score are useful for early prediction of critical illness. AS-LYMPH is the most useful predictor of critical illness on multivariate analysis. RE-MONO# and RE-MONO%/M parameter are useful in distinguishing critical and noncritical non-COVID and COVID-19 patients.

Cytogenetic Risk Stratification of B-Acute Lymphoblastic Leukemia and Its Correlation with Other Prognostic Factors

Purpose of current study was to categorize WHO defined B-Acute Lymphoblastic Leukemia (B-ALL) cases into 3 cytogenetic risk groups (good, intermediate and poor) and to see their correlation with age, NCI risk criteria and treatment response. Clinical and diagnostic details were collected for 78 newly diagnosed B-ALL patients which included bone marrow morphology, flow cytometry immunophenotyping, karyotyping, FISH and RT-PCR. Study cohort comprised 44/78 (56.4%) children including 3 infants and 34/78 (43.6%) adults. Median age for paediatric group was 6 years (3 months-17 years) and for adults was 40.5 years (18 to 75 years). According to NCI risk criteria, excluding infants, 54 (72%) were high risk and 21 (28%) were standard risk. Clonal cytogenetic abnormality was detected in 59/78 cases (75.6%), while 19/78 (24.4%) cases showed normal karyotype. There was significant association of cytogenetic risk groups to age distribution (p value < 0.001) and NCI risk groups (p value < 0.001). There was no significant correlation of CNS involvement with cytogenetic risk groups (p = 0.064). Association of Day 8 steroid response and Day 15 bone marrow status with cytogenetic risk groups was significant (p = 0.006 and p = 0.003 respectively). Post treatment bone marrow status on Day 33 and Day 79 was available for 52 and 42 cases respectively. 9 adults died during induction phase. Day 33 post induction morphological remission was achieved in 51/52 cases (98%) and 1/52 (2.0%) were not in remission. Day 79 post induction morphological remission was achieved in 41/42 cases (98%) and 1/42 (2.0%) were not in remission. Day 33 or End of induction flow MRD (measurable residual disease) was negative in 39/52 (75.0%) patients and positive in 13/52 (25.0%) patients. Day 79 flow MRD was negative in 37/42 (88.1%) and positive in 5/42 (11.9%). Cytogenetic risk groups showed statistically significant Day 33 and Day 79 treatment response (morphologic remission: p = 0.009 and 0.003, flow MRD: p = 0.004 and p = 0.012 respectively). We concluded that cytogenetic risk groups showed statistically significant association with age, NCI risk criteria and treatment response.

HepCCATT: a multilevel intervention for hepatitis C among vulnerable populations in Chicago

BACKGROUND

Hepatitis C infection could be eliminated. Underdiagnosis and lack of treatment are the barriers to cure, especially for vulnerable populations (i.e. unable to pay for health care).

METHODS

A multilevel intervention from September 2014 to September 2019 focused on the providers and organizations in 'the safety net' (providing health care to populations unable to pay), including: (i) public education, (ii) training for primary care providers (PCPs) and case managers, (iii) case management for high-risk populations, (iv) policy advice and (v) a registry (Registry) for 13 health centers contributing data. The project tracked the number of PCPs trained and, among Registry sites, the number of people screened, engaged in care (i.e. clinical follow-up after diagnosis), treated and/or cured.

RESULTS

In Chicago, 215 prescribing PCPs and 56 other health professionals, 86% of whom work in the safety net, were trained to manage hepatitis C. Among Registry sites, there was a 137% increase in antibody screening and a 32% increase in current hepatitis C diagnoses. Engagement in care rose by 18%.

CONCLUSIONS

Hepatitis C Community Alliance to Test and Treat (HepCCATT) successfully targeted safety net providers and organizations with a comprehensive care approach. While there were challenges, HepCCATT observed increased hepatitis C screening, diagnosis and engagement in care in the Chicago community.

Fractional flow reserve versus angiography guided revascularization for patients with multivessel coronary artery disease: a systematic review and meta-analysis of randomized controlled trials

Background

Recently published randomized controlled trials (RCT) have questioned the utility of Fraction Flow Reserve (FFR) to guide revascularization in patients with multivessel coronary artery disease (CAD) as compared to Angiography

Purpose

This current analysis aimed to compare the clinical outcomes associated with FFR guided versus standard angiography-guided revascularization for patients with multivessel CAD using a large number of randomized patients with stable CAD and acute coronary syndrome (ACS)

Methods

We conducted an electronic database search of all published data for RCT that compared FFR versus Angiography for patients with multivessel CAD and reported on subsequent mortality, cardiac death, myocardial infarction, revascularization, and other outcomes of interest. Event rates were compared using a forest plot of odds ratios using a fixed-effects model assuming interstudy heterogeneity.

Results

Eleven RCT (n=6052; FFR = 3043, Angiography = 3027) were included in the final analysis. Mean follow-up period was 1.7 years. In our analysis, FFR guided revascularization as compared to angiography guided revascularization alone was not associated with any significant reduction in overall mortality (OR = 1.10, 95% CI = 0.83–1.47, P=0.47, I2=0), cardiac mortality (OR = 0.95, 95% CI = 0.63–1.45, P=0.42, I2=0), all revascularization (OR = 0.96, 95% CI = 0.80–1.14, P=0.17, I2=31%) or myocardial infarction (OR = 0.99, 95% CI = 0.79–1.23, P=0.33, I2=12%). There was also no difference between two groups in terms of major adverse cardiac or cerebrovascular event [MACCE] (OR = 1.13, 95% CI = 0.90–1.42, P=0.39, I2=5%), major adverse cardiac event [MACE] (OR = 0.86, 95% CI = 0.70–1.07, P=0.55, I2=0), stroke/TIA (OR = 1.61, 95% CI = 0.92–2.82, P=0.36, I2=8%) or target lesion revascularization [TLR] (OR = 0.86, 95% CI = 0.44–1.67, P=0.71, I2=0). Furthermore, sensitivity analysis was conducted to include only studies with ACS patients and studies which used CABG only for revascularization. However, there was no difference between the two groups for any of the above outcomes

Conclusion

There is no difference in clinical outcomes in patients undergoing FFR-guided versus angiography guided revascularization for multivessel CAD

Funding Acknowledgement

Type of funding sources: None.

Artificial intelligence enabled intrusion detection systems for cognitive cyber-physical systems in industry 4.0 environment

In recent days, Cognitive Cyber-Physical System (CCPS) has gained significant interest among interdisciplinary researchers which integrates machine learning (ML) and artificial intelligence (AI) techniques. This era is witnessing a rapid transformation in digital technology and AI where brain-inspired computing-based solutions will play a vital role in industrial informatics. The application of CCPS with brain-inspired computing in Industry 4.0 will create a significant impact on industrial evolution. Though the CCPSs in industrial environment offer several merits, security remains a challenging design issue. The rise of artificial intelligence AI techniques helps to address cybersecurity issues related to CCPS in industry 4.0 environment. With this motivation, this paper presents a new AI-enabled multimodal fusion-based intrusion detection system (AIMMF-IDS) for CCPS in industry 4.0 environment. The proposed model initially performs the data pre-processing technique in two ways namely data conversion and data normalization. In addition, improved fish swarm optimization based feature selection (IFSO-FS) technique is used for the appropriate selection of features. The IFSO technique is derived by the use of Levy Flight (LF) concept into the searching mechanism of the conventional FSO algorithm to avoid the local optima problem. Since the single modality is not adequate to accomplish enhanced detection performance, in this paper, a weighted voting based ensemble model is employed for the multimodal fusion process using recurrent neural network (RNN), bi-directional long short term memory (Bi-LSTM), and deep belief network (DBN), depicts the novelty of the work. The simulation analysis of the presented model highlighted the improved performance over the recent state of art techniques interms of different measures.

Role of oxidative stress in angiogenesis and the therapeutic potential of antioxidants in breast cancer

The escalation of cancer cases globally, especially breast cancer, is of concern. Angiogenesis is hallmark of cancer pathogenesis and plays an important role in cancer progression and metastasis. Pro-angiogenic agents, secreted by tumor cells, form new blood vessels, and produce reactive oxygen species (ROS). ROS promote angiogenesis via two major pathways: namely Vascular Endothelial Growth Factor (VEGF) dependent and non-VEGF dependent pathways. As a consequence of unbalanced ROS overproduction and low antioxidants levels, oxidative stress occurs and promotes angiogenesis in breast cancer tissues. Thus, the potential use of antioxidants as a preventive therapy in breast cancer. Preclinical studies depict that vitamins A and E may counter oxidative stress resulting in reduction of metastasis and viability of breast cancer. Furthermore, clinical studies demonstrate a decline in breast cancer risk in postmenopausal women upon the consumption of antioxidants. Herein, we discuss various pro-angiogenic agents that may play an important role in breast cancer angiogenesis. Moreover, the contribution of oxidative stress in inducing the angiogenic process is extensively reviewed here. Furthermore, the findings of pre-clinical and clinical studies on the use of antioxidants, namely vitamins A and E, in breast cancer are deliberated upon, along with the role of angiogenesis in cancer therapy.

Asymptomatic infection and transmission of COVID-19 among clusters: systematic review and meta-analysis

OBJECTIVES

Countries throughout the world are experiencing COVID-19 viral load in their populations, leading to potential transmission and infectivity of asymptomatic COVID-19 cases. The current systematic review and meta-analysis aims to investigate the role of asymptomatic infection and transmission reported in family clusters, adults, children and health care workers, globally.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

An online literature search of PubMed, Google Scholar, medRixv and BioRixv was performed using standard Boolean operators and included studies published up to 17 August 2021. For the systematic review, case reports, short communications and retrospective studies were included to ensure sufficient asymptomatic COVID-19 transmission data were reported. For the quantitative synthesis (meta-analysis), participant data from a collection of cohort studies focusing on groups of familial clusters, adults, children and health care workers were included. Inconsistency among studies was assessed using I² statistics. The data synthesis was computed using the STATA 16.0 software.

RESULTS

This study showed asymptomatic transmission among familial clusters, adults, children and health care workers of 15.72%, 29.48%, 24.09% and 0%, respectively. Overall, asymptomatic transmission was 24.51% (95% confidence interval [CI]: 14.38, 36.02) among all studied population groups, with a heterogeneity of I² = 95.30% (P < 0.001). No heterogeneity was seen in the population subgroups of children and health care workers. The risk of bias in all included studies was assessed using the Newcastle Ottawa Scale.

CONCLUSIONS

For minimising the spread of COVID-19 within the community, this study found that following the screening of asymptomatic cases and their close contacts for chest CT scan (for symptomatic patients), even after negative nucleic acid testing, it is essential to perform a rigorous epidemiological history, early isolation, social distancing and an increased quarantine period (a minimum of 14-28 days). This systematic review and meta-analysis supports the notion of asymptomatic COVID-19 infection and person-to-person transmission and suggests that this is dependent on the varying viral incubation period among individuals. Children, especially those of school age (i.e. <18 years), need to be monitored carefully and follow mitigation strategies (e.g. social distancing, hand hygiene, wearing face masks) to prevent asymptomatic community transmission of COVID-19.

New era of education: mobile learning of coronary guidewires in cardiovascular medicine

Background

Online education has transformed the way we teach and learn, especially in the midst of a global pandemic. Multiple devices, including coronary guidewires, are required to perform a successful coronary intervention, and understanding the engineering aspect of coronary guidewire technology is paramount.

Purpose

We aim to develop and evaluate a novel teaching tool/mobile learning app to understand a complex guidewire architecture and appropriate wire selection based on a lesion characteristics.

Methods

A guidewire is incredibly complex, consisting of a multitude of technologies allowing a range of tip softness, trackability around curves, and precise torque control. Despite operator preference, the process of choosing an appropriate coronary guidewire has gone mostly unchanged. We envisioned developing the GuidewireAID app with three main parts: 1) wire basics, 2) lesion-based guidewire selection, and 3) cased-based approach. Appropriate teaching cases were selected from a large-volume catheterization laboratory and divided into non-chronic total occlusion (non-CTO) and CTO. Non-CTO cases include simple, calcified, angulated, and bifurcation lesions, as well as thrombotic occlusion and tortuous vessels (Figure 1). Each case is described and analysis is offered on how to select an appropriate wire, followed by teaching points pertinent to the topic.

Results

Twenty-three detailed clinical cases and more than a hundred wires are illustrated in the GuidewireAID app. Case presentation, angiographic analysis, and a thorough understanding of wire characteristics allows the operator to know which wire to use and when it is time to switch, especially when dealing with complex coronary cases.

Conclusion

The GuidewireAID app will help fellows in training (FIT), early career interventionists, and practicing interventional cardiologists understand the complex aspects of a coronary guidewire and appreciate how their nuances could overcome real-world clinical challenging scenarios.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Core Biopsy Diagnosis of ALK Positive Inflammatory Myofibroblastic Tumor of Lung: An Interesting Case

Inflammatory myofibroblastic tumor (IMT) of lung is a rare tumor, accounting for ~0.7% of all lung tumors with varied clinical and radiological presentations. The origin of this tumor is unknown but some studies suggest that it might be a true neoplasm as some mutations on chromosome 2p23 of anaplastic lymphoma kinase (ALK) have been found to be related to this tumor. The morphology of IMT is quite vague and the histopathological diagnosis is predominantly given on excision specimens; in fact, only 6.3% of cases are diagnosed based on analysis of biopsy specimens alone. We illustrate a case of IMT diagnosed in a young male on core biopsy, where the case presented with a large tumor in the lung with metastases to multiple sites that was hence unresectable. Post 3 months of treatment with Crizotinib, there was significant reduction in the tumor size. Another interesting finding was that the ALK immunostain, which helped immensely in the diagnosis, was appreciated better on the Ventana platform rather than on the Dako platform.

Novel patterns of response under immunotherapy

Novel patterns of response and progression to immunotherapy have been reported that are not observed with conventional cytotoxic or targeted anticancer treatments. A major breakthrough with immunotherapy is its potential to achieve durable responses in a subset of patients with advanced cancer that can be maintained several years even after stopping the treatment. No standardized definition of durable response exists in the literature, and the optimal duration of treatment in case of durable response is not clearly established. However, the majority of patients do not respond to immunotherapy. Initially reported in advanced melanoma patients, pseudoprogression occurs when tumor index lesions regress after initial progression, supporting the concept of treating some patients beyond progression. Overall, reported rates of pseudoprogression never exceeded 10%, meaning that the large majority of patients who have a disease progression will not eventually respond to treatment. The decision to pursue treatment beyond progression must therefore only be taken in carefully selected patients with clinical benefit, who did not experience severe toxicities with immunotherapy. Conversely, rapid progressions, called hyperprogressions, were reported by several teams with rates ranging from 4% to 29%. These observations need to be confirmed from randomized trials. It is essential to interrupt the treatment in patients with hyperprogression, in order to switch to another potentially active treatment. Finally, some patients experience dissociated responses, with some lesions shrinking and others growing. Local treatment with surgery or radiotherapy for growing lesions may be considered. Several immune-specific-related response criteria were developed to better capture benefits of immunotherapy. These criteria only address the pseudoprogression pattern of response, and do not capture the other patterns of response such as hyperprogression and dissociated response. The classic RECIST remains a reasonable and meaningful method to assess response to immunotherapy in the clinic.

Abstract PD3-08: Assessment of the tumor immune environment in inflammatory breast cancer treated with neoadjuvant dual-HER2 blockade

Background: Inflammatory breast cancer (IBC) is an aggressive form of breast cancer that remains relatively understudied. We examined the efficacy of neoadjuvant dual-HER2 blockade (trastuzumab (H) and pertuzumab (P)) combined with paclitaxel (T) in HER2+ IBC, including a planned analysis to elucidate associations between the tumor immune microenvironment profile and response to therapy.

Methods: An IRB-approved, single-arm phase II trial for patients (pts) with newly diagnosed HER2+ IBC was conducted. Pts had a pre-treatment biopsy of the affected breast (D1) followed by a loading dose of HP. A second biopsy was performed 1 week (wk) later (D8), when T (80mg/m2/wk x 16 wks) was added to HP. Responding pts underwent modified radical mastectomy (MRM) where residual disease was collected. The primary objective was to determine the rate of pathologic complete response (pCR) defined as ypT0/isN0. Residual Cancer Burden (RCB) was also determined. Tumor specimens from D1, D8 and MRM were assessed for disease cellularity and scored for percentage of tumor infiltrating lymphocytes (TILs): low=0-10%, intermediate=11-59%, high&gt;60%. RNA-sequencing was performed on tumor tissue from D1 and D8 to explore the impact of short-term HP treatment on the tumor transcriptomic profile and to identify potential predictors of pCR.

Results: 23 pts with HER2+ IBC were enrolled between 8/2013-6/2017. Mean age was 48 years (range 32-74); 11 pts (48%) had estrogen and progesterone receptor (ER/PR) negative disease. Matched tumor biopsies (D1, D8) were obtained in all 23 pts; 21 underwent MRM; 1 was lost to follow-up and 1 had disease progression. In the intent to treat analysis, 10/23 (43%) pts achieved a pCR and 7 (30%) had RCB-1. Ten of the 22 evaluable pts achieved a pCR (45.5%). TILs were evaluable in 20/23 (87%) matched tumor biopsies (D1, D8). Among the D1 biopsy specimens: 19 (95%) had low levels, 2 (10%) had intermediate levels, and none had high levels. When D1 TIL levels were compared with D8 levels, 3(15%) had an increase in TILs, 16(80%) had no change in TIL levels, and 1(5%) had a decrease in the level of TILs. Both samples with intermediate levels and 2 of 3 samples with high levels of TILs on D1 and D8 were seen in ER/PR negative disease. An evaluation of biopsy specimens associated with subsequent pCR using GO enrichment analysis from the RNA-Seq data showed significant upregulation of several immune-process related gene expression signatures both at D1 and D8 (e.g. antigen processing and presentation, TCR signaling, NK cell cytotoxicity, p-value: 2.99E-48 to 1.39E-16) when compared with those associated with residual disease at the time of MRM. Across the entire cohort, D8 biopsies showed evidence of upregulated anti-tumor immunity compared to D1 biopsies (p-value: 9.57E-06 to 0.012). Notably, this change from D1 to D8 was largely restricted to tumors that achieved a pCR.

Conclusion: THP for 16 weeks was a highly effective treatment for HER2+ IBC. Immune activation as determined by gene expression signatures predicted pCR, and moreover upregulation of anti-tumor immunity after 1 wk of HP might further predict a complete pathologic response to therapy. ClinicalTrials.gov identifier: NCT01796197

Citation Format: Pernas S, Goel S, Harrison BT, Hu J, Johnson N, Regan M, Chichester LA, Nakhlis F, Schlosnagle EJ, Winship G, Guerriero JL, Parsons H, Mittendorf EA, Overmoyer B. Assessment of the tumor immune environment in inflammatory breast cancer treated with neoadjuvant dual-HER2 blockade [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 PD3-08.

Abstract P6-18-10: A phase 1b/2 study of ribociclib plus trastuzumab for the treatment of advanced, treatment-refractory HER2-positive breast cancer

Introduction:

Despite the success of anti-HER2 therapy, acquired resistance usually develops in the metastatic setting. CDK4/6 pathway activity has been identified as a mediator of this resistance, and in preclinical studies the combination of CDK4/6 and HER2 blockade can be more effective than either therapy alone. We conducted a single-arm phase 1b/2 study of the CDK4/6 inhibitor ribociclib given with trastuzumab or T-DM1 to subjects with advanced, treatment-refractory HER2-positive breast cancer. The results of the trastuzumab cohort are presented below. The primary objective was to determine the clinical benefit rate (CBR) at 24 weeks, and secondary endpoints included objective response rate (ORR), progression-free survival (PFS), and adverse events.

Methods: Individuals with locally advanced or metastatic, measurable HER2-positive breast cancer were eligible. All subjects must have previously received trastuzumab, pertuzumab, and T-DM1 as (neo)adjuvant or metastatic therapy. There was no limit on the number of prior lines of treatment. Patients with previous CDK4/6 inhibitor exposure, QTcF &gt; 450msec on EKG, or without stable brain metastases were excluded. An initial safety run-in phase (with dose-limiting toxicity (DLT) monitoring) included six subjects who received trastuzumab (8mg/kg loading then 6mg/kg IV three-weekly) and ribociclib 400mg PO daily on a continuous schedule (cycle length 21 days). The study had a two-stage design. The first stage required 20 patients, at least 6 of whom must have demonstrated clinical benefit (CR+PR+ SD&gt;24 weeks) in order to recruit 15 more patients to the second stage. All patients with accessible disease underwent metastatic tumor biopsies at baseline and C2D1.

Results: 13 patients were enrolled (6 in the safety run-in and 7 in the expansion cohort). One patient was found to have HER2-negative disease and did not receive treatment. Patient characteristics are shown in Table 1 No DLTs were observed during the safety run-in phase, and ribociclib was thus used at 400mg po daily for the expansion cohort. Grade 3/4 toxicities were observed in 5 patients (41.7%) and included neutropenia (n=2), and fatigue, pain, and muscle weakness (all n=1). No patient demonstrated QTc prolongation &gt;480 msec, or grade 3/4 LFTs. 1/12 patients ((8.3%); 95% CI 0.2%-38.5%) achieved stable disease&gt;24 weeks; no objective responses were observed, and median PFS was 41.5 days. The trastuzumab portion of study was closed early due to limited clinical activity observed (the T-DM1 with ribociclib cohort remains open).

Table 1Age (median, range)50.5 (42 - 71)Number of prior lines of systemic therapy for metastatic disease (median, range)5.5 (0-14)Number with Hormone receptor-positive disease (%)8 (67 %)Number of metastatic sites (median, range)2.5 (2 - 5)

Conclusions: The combination of trastuzumab and ribociclib (400mg daily continuous schedule) is safe, with no new safety signals observed. The limited activity seen in this heavily pretreated population suggests that future efforts to incorporate CDK4/6 inhibition should be limited to a less extensively treat population.

Citation Format: Goel S, Spring L, Rees R, Andrews C, Tahara RK, Mayer EL, Bardia A, Winer EP, Tolaney SM. A phase 1b/2 study of ribociclib plus trastuzumab for the treatment of advanced, treatment-refractory HER2-positive breast cancer [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 P6-18-10.

Abstract TS3-2: Modulation of anti-tumor immunity using CDK4/6 inhibitors

Several pharmacological inhibitors of cyclin-dependent kinases 4 and 6 (CDK4/6) have now been approved for the treatment of metastatic estrogen receptor-positive breast cancer. Although CDK4/6 inhibitors were initially developed to prevent cancer cell proliferation, preclinical studies have now demonstrated that they can also exert other biological effects in solid tumors including augmentation of anti-tumor immunity. The detailed mechanisms underlying this are currently under investigation, and likely include enhanced antigen presentation by tumor cells as well as an increase in the ratio of effector to regulatory T lymphocytes. In this presentation, I will discuss our current understanding of how CDK4/6 inhibitors might stimulate anti-tumor immune responses, focusing on breast cancer. I will also discuss if and how this unexpected phenomenon might be leveraged for therapeutic benefit.

Citation Format: Goel S. Modulation of anti-tumor immunity using CDK4/6 inhibitors [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 TS3-2.

The ProSeal™ Laryngeal Mask Airway is an Effective Alternative to Laryngoscope-Guided Tracheal Intubation for Gynaecological Laparoscopy

We tested the hypothesis that the ProSeal™ laryngeal mask airway is superior to laryngoscope-guided tracheal intubation for gynaecological laparoscopy. One-hundred and eighty consecutive patients (ASA grade 1-2, aged 18-80y) were divided into two equal-sized groups for airway management with the ProSeal™ laryngeal mask airway or tracheal tube. Induction was with fentanyl/propofol, maintenance with sevoflurane and muscle relaxation with atracurium. The following primary variables were tested: time to achieve an effective airway, ventilatory capability, peak airway pressure before and after pneumoperitoneum, duration of surgery and pneumoperitoneum and haemodynamic responses. Data about gastric size, airway trauma and sore throat were collected. The number of attempts for successful insertion were similar, but effective airway time was shorter for the ProSeal™ laryngeal mask airway (20±2s vs 37±3s, P<0.001). All devices were successfully inserted within three attempts. There was no episode of failed ventilation or hypoxia. The haemodynamic stress responses to insertion and removal were greater for the tracheal tube than the ProSeal™ laryngeal mask airway. The duration of surgery, duration of pneumoperitoneum and intraabdominal pressures were similar. Gastric size was similar at the start and end of surgery. There were no differences in the frequency of complications or sore throat.

We conclude that the ProSeal™ laryngeal mask airway is a similarly effective airway device to conventional laryngoscope-guided tracheal intubation for gynaecological laparoscopy, but is more rapidly inserted and associated with an attenuated haemodynamic response to insertion and removal.