A reference high-pressure CH4 adsorption isotherm for zeolite Y: results of an interlaboratory study

This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess methane adsorption isotherms on NIST Reference Material RM 8850 (Zeolite Y), at 25 °C up to 7.5 MPa. Twenty laboratories participated in the study and contributed over one-hundred adsorption isotherms of methane on Zeolite Y. From these data, an empirical reference equation was determined, along with a 95% uncertainty interval (Uk=2). By requiring participants to replicate a high-pressure reference isotherm for carbon dioxide adsorption on NIST Reference Material RM 8852 (ZSM-5), this interlaboratory study also demonstrated the usefulness of reference isotherms in evaluating the performance of high-pressure adsorption experiments.

Different mother and daughter manifestations due to very high cholesterol-containing lipoproteins

Familial hypercholesterolemia (FH) is an autosomal codominant genetic disorder associated with defective hepatic uptake of circulating low-density lipoproteins (LDL), which can lead to premature atherosclerotic cardiovascular disease (ASCVD). Evidence suggests elevated lipoprotein(a) (Lp(a)) levels in FH patients may also increase their ASCVD risk. We present a case series of 2 FH patients where a daughter has a higher ASCVD burden than her mother due to the daughter having elevated Lp(a). This underscores the importance of including Lp(a) in cascade lipid screening in FH patients and their first-degree relatives.

FRI0516 FACTORS ASSOCIATED WITH DECREASED CERVICAL CANCER SCREENING IN WOMEN WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that carries an increased risk for both viral illnesses and malignancies, including a greater risk for both human papilloma virus (HPV) infection and cervical cancer. Due to this increased risk, the American Society of Colposcopy and Cervical Pathology guidelines for SLE patients recommend more frequent cervical cancer screening. Few studies have examined patient characteristics associated with decreased cervical cancer screening in patients with autoimmune disease, specifically SLE.

Objectives:

To estimate cervical cancer screening rates in women with recently diagnosed SLE, and to identify characteristics associated with decreased screening.

Methods:

We identified women with an initial diagnosis of SLE in the United States MarketScan Commercial Claims and Encounter (CCAE, age 18-64) administrative claims database. We included patients with at least three claims with a lupus diagnosis (first and last at least >90 days apart), no lupus claims within the year before initial claim, and who had been on antimalarial drugs for at least 90 days. We excluded all patients with a previous claim for hysterectomy.

Cervical cancer screening was ascertained using diagnosis and procedure codes within 1 year before and 2 years after the first SLE claim. Our covariates included the year of first SLE claim (2001-2014), age at first SLE claim, comorbidity score, insurance type, geographical region, and prescriptions for multiple types of corticosteroids. Control patients included age-matched females without autoimmune disease. Univariate comparison and multivariate logistic regression models were built to evaluate determinants of screening.

Results:

We included 4,316 SLE patients (median age 45) and 86,544 control patients. The screening rate in SLE patients was 73.4% vs 58.5% in the controls (P < 0.001). The screening rate was 71% in 2001, increased to 75% in 2004, then decreased to 70% in 2014 (trend P =0.005). In the multivariate model the following factors were associated with decreased cervical cancer screening: year of first SLE claim 2012-2014 versus 2001-2005 (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.53 – 0.84, P < 0.001); older age 61-64 versus 21-30 (OR 0.27, 95% CI 0.19 – 0.39, P < 0.001); comorbidity score of ≥2 versus <2 (OR 0.71, 95% CI 0.6 – 0.83, P < 0.001); and use of corticosteroids for ≥ 90 days versus <90 days (OR 0.73, 95% CI 0.59 – 0.9, P = 0.003). Insurance type and geographical region were not associated with cervical cancer screening.

Conclusion:

About three quarters of women with SLE underwent cervical cancer screening within 3 years of their first lupus claim, at higher rates than controls. However, there was a concerning downward trend in screening rates in recent years. In addition, higher risk populations for cervical cancer (older age, increased comorbidities, and longer duration of corticosteroids) had lower screening rates. These findings highlight the need to enhance education for healthcare providers to improve utilization of screening in women with SLE at high risk of cervical cancer.

Disclosure of Interests:

Sebastian Bruera: None declared, Richard Zogala: None declared, Xiudong Lei: None declared, Xerxes Pundole: None declared, Hui Zhao: None declared, Sharon Giordano: None declared, Jessica Hwang Grant/research support from: MERCK grant funding unrelated to SLE., Maria Suarez-Almazor: None declared

OP0073 RISK OF DEVELOPING RHEUMATIC DISEASES IN PATIENTS WITH PALINDROMIC RHEUMATISM IN SOUTH KOREA: A NATION-WIDE POPULATION-BASED STUDY

Background:

Palindromic rheumatism (PR) has known to be three patterns of disease course: clinical remission of attacks, persistent attacks, and evolution to chronic arthritis or systemic disease. The spectrum in progression to chronic diseases of PR, however, is quite variable; rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), Sjögren’s syndrome (SjS), ankylosing spondylitis (AS), relapsing polychondritis (RP), Behçet’s disease (BD), sarcoidosis, and psoriatic spondylitis and arthropathy. Because of the small numbers in case-control studies and too aged investigations, now we needs to shed new light on the fate of PR.

Objectives:

The aim was to investigate the epidemiology of PR and the risk of developing various rheumatic diseases compared with non-PR individuals, employing the National Health Insurance Service (NHIS) medical claims data, which covers all medical institutions of South Korea.

Methods:

The study used 2007-2018 claims data from the Korean Health Insurance Review and Assessment Service (HIRA). The identified 19,724 PR patients from 2010 to 2016 were assessed for the incidence rate (IR) compared with the population in the given year by 100,000 person-year (py). The date of diagnosis was the index date. After matching with non-PR individuals (1:10) for age, sex and the year of index date, we calculated the hazard ratios (HRs) with 95% confidence intervals (CIs). The risk of developing the various rheumatic diseases and adult immunodeficiency syndrome (AIDS) as the outcome diseases in PR cohort was estimated. This risk was compared with that of matched non-PR cohort.

Results:

Of 19,724 PR patients (8,665 males and 11,059 females), the mean age was 50.2 ± 14.9 years (47.7 ± 14.4 years in males and 52.6 ± 14.9 years in females,p< 0.001). The ratio of male to female patients with PR was approximately 1:1.28. The annual IR of PR was 7.02 (6.92-7.12) per 100,000 py (6.22 (6.09-6.35) and 7.80 (7.66-7.95) per 100,000 py in males and females, respectively). The mean duration to develop the outcome diseases was significantly shorter in PR cohort compared that of non-PR cohort (19.4 vs. 35.8 months,p< 0.001). The most common outcome disease was RA (7.34% of PR patients; 80.0% of total outcome diseases), followed by AS, SLE, BD, SjS, MCTD, DM/PM, SSc, RP, psoriatic arthropathy, and AIDS in PR cohort. The patients with PR had an increased risk of RA (HR 46.6, 95% CI [41.1-52.7]), psoriatic arthropathy (44.79 [15.2-132.4]), SLE (24.5 [16.2-37.2]), MCTD (22.0 [7.7-63.3]), BD (21.0 [13.8-32.1]), SjS (12.4 [8.5-17.9]), AS (9.0 [6.7-12.2]), DM/PM (6.1 [2.6-14.8]), and SSc (3.8 [1.5-9.6]) but not of AIDS. The risk of developing RA was greater in male patients (HR 58.9, 95% CI [45.6-76.2] vs. 43.2 [37.4-49.8],pfor interaction = 0.037) while female patients encountered a higher risk of developing AS (15.8 [8.9-28.1] vs. 7.2 [5.0-10.3],pfor interaction = 0.023). The risk of developing RA, SLE, SjS, and BD were significantly more highly affected in younger age (pfor interaction < 0.001, = 0.003, 0.002, and 0.017, at each).

Conclusion:

This nationwide, population-based cohort study demonstrated that patients with PR had an increased risk of developing various rheumatic diseases, not only RA but also psoriatic arthropathy. Therefore, patients with PR needs to be cautiously followed up for their potential of diverse outcome other than RA: RA, SLE, SjS, and BD in younger patients, RA in males, and AS in females, in particular.

Disclosure of Interests:

None declared

Knowledge, attitudes and behaviour towards needlestick injuries among junior doctors

BACKGROUND

Needlestick injuries (NSIs) are common healthcare-related injuries and possible consequences include blood-borne infections. Despite that, a large proportion of NSIs are not reported.

AIMS

To estimate the prevalence of under-reporting of NSIs and to evaluate the knowledge, attitude and behaviour towards NSIs among junior doctors in a tertiary hospital in Singapore.

METHODS

An explanatory sequential mixed-methods design was employed. Quantitative data were collected through questionnaires completed by 99 junior doctors. Descriptive statistics and bivariate analysis were performed to evaluate socio-demographic characteristics, NSI history and NSI reporting practices. Qualitative data were collected through 12 in-depth interviews. Participants were purposively recruited, and semi-structured topic guides were developed. Data were analysed using a thematic approach.

RESULTS

Fifty-two per cent of respondents had history of NSI. Of those with history of NSI, 31% did not report injury. NSI reporters were 1.52 times as likely to be aware of how to report injury (P < 0.05), and 1.63 times as likely to feel that reporting benefits their health (P < 0.01) compared with non-reporters. NSI reporters were 83% more likely to report a clean NSI (P = 0.05). For non-reporters, the main reasons for not reporting were perceived low risk of transmission (41%) and lack of time to report (35%). Themes identified in the qualitative data include perceived benefits, perceived barriers, perceived threats, cues to action and organizational culture.

CONCLUSION

Under-reporting of NSIs may have significant implications for patients and healthcare workers. Addressing identified factors and instituting targeted interventions will help to improve reporting rates.

Abstract ES10-2: Understanding breast cancer using a developmental perspective

Parallels among embryonic development, stem cells, and cancer have long been recognized. We identified, isolated, and characterized stem cells that first become committed to a mammary fate during embryogenesis; we refer to these cells as fetal mammary stem cells (fMaSCs). Lineage tracing, in vitro sphere formation, and in vivo transplantation studies by our group and many others all confirm that cells in the embryo are the bipotent progenitors of the mammary gland. There is debate, however, on whether such bipotent cells persist into the adult, or whether the luminal and basal lineages are maintained by unipotent progenitors. To gain insight into the relationships between fMaSCs and breast cancer, and to investigate their potential persistence in the adult, we have applied bulk and single cell RNA-sequencing (sc-RNA-seq) and single nucleus ATAC-sequencing (snATAC-seq) throughout mammary development. The results to be discussed demonstrate that fMaSC transcriptomes are heterogeneous, but all share co-expression of genes associated with luminal and basal cell fates. This fits a model in which the bipotent state is created by a balance of lineage specifiers. We also find that the fMaSC transcriptome is highly enriched in basal-like human breast cancers and identify potential embryonic pathways that correlate with poor prognosis. We used a variety of computational tools to infer the gene expression programs that ensue when fMaSCs commit to luminal and basal states. The data from scRNA-seq and snATAC-seq demonstrate that the transitions are gradual, not precipitous, and that luminal and basal cells exhibit significant transcriptomic and epigenetic heterogeneity. This challenges the notion that the mammary gland consists of discrete cell types defined by rigid transcriptomic parameters, and reveals a potential for intrinsic phenotypic plasticity of normal mammary cells. Using the combined databases, we identified Sox10 as a significantly differentially expressed cell state regulator. We show that tumors are heterogeneous with regard to Sox10 expression, and that locally invasive cells tend to express high Sox10 levels. Elevated Sox10 correlates with acquisition of a neural-crest like, EMT-related state. Implications for interception of metastasis by targeting neural crest-like cells will be discussed. Finally, we have generated a web resource that is available to the scientific community to enable the transcription and epigenetic characteristics of any gene of interest to be tracked through mammary development (https://wahl-labsalk.shinyapps.io/Mammary_snATAC/).

Citation Format: GM Wahl, Z Ma, C Chung, C Dravis, BT Spike, RR Giraddi, O Balcioglu, C Fan, B Hagos, R Heinz, Herrera-Valdez J, X Hou, J Hwang, R Lasken, G Luna, NE Lytle, EM Mehrabad, M Novotny, CM Perou, O Poirion, S Preissl, B Ren, T Reya, CL Trejo, KT Varley. Understanding breast cancer using a developmental perspective [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr ES10-2.

P5731Optimal blood pressure in diabetic hypertensive patients with overt proteinuria

Background

Evidence for the benefit of intensive blood pressure lowering in diabetic nephropathy is not clear at this time. The objective of this study was to demonstrate whether lower mean blood pressure (BP) in treated hypertensive patients with diabetic nephropathy is associated with better prognosis.

Methods

From the National Health Insurance Service (NHIS) Health Examination Database, diabetic hypertensive subjects with proteinuria between 2009 and 2010 were selected and followed-up until 2015 (N=8,663). Mean of the recorded systolic and diastolic BP during follow-up health examinations were stratified into five categories (SBP: <120, 120 to <130, 130 to <140, 140 to <150, and ≥150 mmHg; DBP: <70, 70 to <80, 80 to <90, 90 to <100, and ≥100 mmHg). All-cause death, myocardial infarction (MI), stroke, and renal outcome (progression to end stage renal disease or doubling of serum creatinine) were examined by Cox proportional hazard models with the propensity scores adjusted method.

Results

Compared to SBP of 130 to <140 mmHg, SBP of 120 to <130 mmHg was associated with lower risk of all-cause death (HR=0.78; 95% CI, 0.64–0.95), stroke (HR: 0.65; 95% CI, 0.45–0.94), and renal outcome (HR: 0.81; 95% CI, 0.68–0.97). SBP of <120 mmHg was associated with benefit for renal outcomes (HR: 0.69; 95% CI 0.55–0.88) but not with elevated risk of other outcomes. Compared to DBP of 80 to <90 mmHg, DBP of 70 to <80 mmHg were associated with lower risk of all-cause death (HR: 0.75; 95% CI, 0.64–0.88) but with higher risk of MI (HR: 1.52; 95% CI, 1.05–2.21). DBP of <70 mmHg was associated with reduced risk of all-cause death (HR: 0.79; 95% CI, 0.64–0.98).

Conclusion

In diabetic hypertensive subjects with overt proteinuria, deterioration of renal function decreased with decreasing SBP and the lowest risk of all-cause death and stroke were observed in SBP <130 mmHg. Low DBP was associated with low risk of all-cause death but there was a J curve phenomenon for MI in DBP of 70 to <80 mmHg.

P10.01 Anti-migration and anti-invasion effects of curcumin via suppression of fascin expression in glioblastoma cells

BACKGROUND

The natural compound Curcumin was known to inhibit migration and invasion of glioblastoma (GBM) cells. Fascin, a kind of actin-binding proteins, is correlated with migration and invasion of GBM cells. The purpose of this study was to investigate anti-migration and anti-invasion effects of Curcumin via suppression of fascin expression in GBM cells.

MATERIAL AND METHODS

U87 cell line was used as an experimental model of GBM. Fascin was quantified by Western blot analysis. And, the signal transducer and activator of transcription 3 (STAT3), known to play an important role in migration and invasion of tumor cells, were analyzed by sandwich-ELISA. Migration and invasion capacities were assessed by attachment, migration and invasion assays. Cellular morphology was demonstrated by immunofluorescence.

RESULTS

At various concentrations of curcumin and exposure times, fascin expression decreased. After temporarily exposure to 10μM/L Curcumin during 6 hours as less invasive concentration and time, fascin expression temporarily decreased at 12 hours (18.4%, p=0.024), and since then recovered. And, the change of phosphrylated STAT3 level also reflected the temporarily decreased pattern of fascin expression at 12 hours (19.7%, p=0.010). Attachment, migration, and invasion capacities consistently decreased at 6, 12, and 24 hours. And, immunofluorescence showed the change of shape and the reduction of filopodia formation in cells.

CONCLUSION

Curcumin is likely to suppress the fascin expression in GBM cells, and this might be a possible mechanism for anti-migration and anti-invasion effects of Curcumin via inhibition of STAT3 phosphorylation.

P14.27 The significance of multicentric noncontrast-enhancing lesions distant from surgically resected glioblastoma: Case series of 3 patients

BACKGROUND

Glioblastoma is the most malignant primary brain tumor. The tumor location and multiplicity plays an important role in surgical and further treatment. The incidence of multiple lesions at the time of diagnosis was known as 1–20%, which showed a poor prognostic factor. Most researches has focused on multiple contrast-enhancing lesions, however, multicentric non-enhancing lesions distant from glioblastoma has been rarely evaluated. The authors reported the case series of the patient who showed multicentric non contrast-enhancing lesions without connection to histologically-proven glioblastoma.

MATERIAL AND METHODS

Multicentric non contrast-enhancing lesions were defined as areas of FLAIR hyperintensity and mass effect without post-contrast enhancement, separated from the histologically-proven glioblastoma in a newly diagnosed disease. Three patients who showed distant non-enhancing lesions with appearance of a multicentric low-grade glioma were included in this study. The typical enhancing lesions were surgically resected and standard chemo-radiotherapy was followed in all patients.

RESULTS

All patients were male and their age was 38, 60 and 65 years old respectively. Multicentric tumor location was as follows: Case 1, left frontal lobe with non-enhancing lesion in left parahippocampal gyrus; Case 2, left parietal with non-enhancing lesion in left anteromedial temporal lobe; Case 3, left thalamus with non-enhancing lesions in both basal frontal and right temporal lobe. Pathologically, the resected enhancing tumor revealed glioblastoma in 2 patients and diffuse midline glioma in 1. All tumors were IDH-wild type. The resected enhanced lesion showed no progression but all non-enhancing lesions developed contrast-enhancing tumors at 3, 13 and 17 months after initial treatment, with high tracer uptake on 18FDG-PET or 18FDOPA-PET. Despite multidisciplinary treatment, two patients died from disease progression at 30 and 32 months after diagnosis and one patient is still alive with overall survival of 15 months.

CONCLUSION

The appearance of multicentric non-enhancing lesions distant from a typically enhancing tumor showed an uncommon finding in glioblastoma and poor prognostic features. These lesions progress faster than expected for a low-grade glioma. These lesions should be distinguished from typical low-grade glioma and should be considered more advanced lesions than their appearances suggest.

Serum Vitamin D and Age-Related Muscle Loss in Afro-Caribbean Men: The Importance of Age and Diabetic Status

BACKGROUND

Prospective studies examining the potential association of vitamin D with age-related muscle loss have shown inconsistent results.

OBJECTIVE

To examine the association between baseline serum 25-hydroxyvitamin D (25(OH)D), 1,25-dihydroxyvitamin D (1,25(OH)2D), and prospective change in lean mass with aging in African ancestry population. We also determined if associations were modulated by age and diabetes mellitus (DM).

DESIGN

Prospective observational cohort study.

SETTING

Data were collected from a random sub-sample of 574 men, participants of the Tobago Bone Health Study (TBHS).

PARTICIPANTS

574 Afro-Caribbean men, aged 43+ years (mean age: 59.1 ± 10.5), who were randomly selected as the participants in both the baseline and the follow-up visits.

MEASUREMENTS

Baseline fasting serum 25(OH)D was measured using liquid chromatography mass spectrometry (LC-MS/MS), and and 1,25(OH)2D was measured using radioimmunosassay (RIA). Changes in dual-energy X-ray absorptiometry (DXA)-measured appendicular lean mass (ALM), and total body lean mass (TBLM) were measured over an average of 6.0 ± 0.5 years. The associations of 25(OH)D and 1,25(OH)2D with ALM and TBLM were assessed by multiple linear regression model after adjusting for potential confounders.

RESULTS

When stratifying all men into two groups by age, greater baseline 25(OH)D and 1,25(OH)2D levels were associated with smaller losses of ALM and TBLM in older (age 60+ years) but not in younger (age 43 - 59 years) men. When stratifying by DM status, the associations of 25(OH)D and 1,25(OH)2D with declines in ALM and TBLM were statistically significant only in prediabetic, but not among normal glycemic or diabetic men.

CONCLUSION

Higher endogenous vitamin D concentrations are associated with less lean mass loss with aging among older and prediabetic Afro-Caribbean men independent of potential confounders. Our findings raise a possibility that maintaining high serum vitamin D level might be important for musculoskeletal health in elderly and prediabetic African ancestry men.

Effect of different doses of ketamine with low-dose rocuronium on intubation conditions in children: prospective randomized double blind trial

OBJECTIVE

The effect of ketamine on intubation condition, when used as an induction agent with low-dose rocuronium, is unknown. This study aimed to compare the effects of three doses of ketamine used with 0.3 mg/kg rocuronium and 1 µg/kg fentanyl on intubation conditions in children undergoing short elective surgery.

PATIENTS AND METHODS

The study was performed as a prospective, randomized double-blind clinical trial. A total of 60 children aged 2 to 12 years, who were scheduled for inguinal herniorrhaphy under general anesthesia, were randomly allocated into three groups on the basis of ketamine dose: 1 mg/kg (Group K1, n = 20), 1.5 mg/kg (Group K1.5, n = 20), and 2 mg/kg (Group K2, n = 20). The primary outcome was the intubation condition. Other assessments included hemodynamic data, recovery profile, adverse events in the postanesthetic care unit (PACU) and use of fentanyl as a rescue analgesic in the PACU were also assessed.

RESULTS

The occurrence of a clinically acceptable intubation condition increased with the use of an increased dose (≥ 1.5 mg/kg) (K1/K1.5/K2: 30%/65%/65%; p=0.038, for trends p=0.028). Hemodynamic data, recovery profile and adverse events in PACU showed no difference among groups. Fentanyl dose used in the PACU was higher in K1 than K2 and the number of patients requiring rescue analgesics in the PACU decreased in accordance with the dose of ketamine (K1/K1.5/K2: 30%/15%/0%; p=.031, for trends p=0.013).

CONCLUSIONS

Different intubation conditions were observed on the basis of ketamine dose used in conjunction with 0.3 mg/kg rocuronium and fentanyl 1 µg/kg. Ketamine dose ≥ 1.5 mg/kg with low-dose rocuronium should be used to improve intubation conditions in pediatrics.

Abstract OT3-04-04: A randomized phase II study of pembrolizumab in combination with carboplatin versus carboplatin alone in breast cancer patients with chest wall disease, with immunologic and genomic correlative studies

Background: Thirty percent of patients with breast cancer may experience chest wall recurrence, which is associated with a higher risk of developing distant metastases and a poor prognosis. Cancer cells may evade immune rejection through the programmed cell death 1 (PD-1) pathway. Pembrolizumab, an anti-PD-1 antibody, binds PD-1 and inhibits its interaction with the programmed death ligand 1 (PD-L1) to facilitate tumor immune rejection. We hypothesize that pembrolizumab may be an effective therapy in chest wall recurrence, given the inflammatory nature, and the high expression of PD-1 in tumors with lymphovascular invasion. Platinum agents may enhance anti-tumor immunity in a synergistic manner, and the combination of pembrolizumab and carboplatin has demonstrated efficacy in advanced lung cancer. In this study, the combination of pembrolizumab and carboplatin is being evaluated in breast cancer patients with chest wall disease.

Methods: This is a randomized phase II study of breast cancer patients with advanced, unresectable breast cancer involving the chest wall, being conducted through the Translational Breast Cancer Research Consortium (TBCRC). Patients may have hormone resistant disease (at least 2 prior lines of hormone therapy), triple negative breast cancer, or refractory HER2+ disease for enrollment. They may have other sites of distant metastases, have received any number of prior lines of therapy, have had prior surgery, but prior chest wall radiation is not necessary. Eighty-four patients at 7 TBCRC sites will be randomized 2:1 to treatment with pembrolizumab 200 mg IV and carboplatin AUC 5 IV every 3 weeks followed by pembrolizumab 200 mg IV alone every 3 weeks (Arm A, n=56) or carboplatin AUC 5 IV every 3 weeks (Arm B, n=28), with an option for patients in Arm B to cross-over to single agent pembrolizumab 200 mg IV every 3 weeks (arm Bx) on progression. Patients will undergo imaging with CT chest, abdomen, and pelvis at baseline and every 2 cycles of treatment for response evaluation. The primary endpoint is the disease control rate in the chest wall and distant sites at 18 weeks of treatment, and this study is powered to determine a 20% difference in disease control rates between arms A and B (hazard ratio of 0.52, α= 0.10, β= 0.20). After 18 patients are enrolled into Arm B, an interim analysis for futility will be conducted to enable early closure of that arm for lack of efficacy. Secondary endpoints in the study are toxicity, progression free survival, and response based on PD-L1 expression and irRECIST. Exploratory endpoints, which will be studied using peripheral blood testing and chest wall tumor biopsies at baseline and after 2 cycles of treatment, include determining associations of response with changes in tumor and peripheral blood immune composition, soluble PD-L1 expression, circulating tumor cells, cell free DNA, and tumor PD-L1 and MYC genomic expression. Ultimately this study promises to improve our understanding of checkpoint inhibition and chemotherapy for chest wall disease, and the underlying mechanism of action. This study is open for enrollment and 2 patients are currently enrolled. (NCT03095352).

Citation Format: Vidula N, Goga A, Hwang J, Liu MC, Park BH, Nanda R, Pohlmann PR, Storniolo AM, Brufsky A, Abramson V, Rugo HS. A randomized phase II study of pembrolizumab in combination with carboplatin versus carboplatin alone in breast cancer patients with chest wall disease, with immunologic and genomic correlative studies [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 OT3-04-04.