P5350Atrial fibrillation prediction using P wave signal-averaged ECG in patients with embolic stroke of undetermined source

Background

Approximately 10–25% of ischemic strokes are of unknown origin. Determining their potential association with subclinical atrial fibrillation (SCAF) is important for proper secondary prevention. We investigated whether SCAF can be predicted by assessing the atrial substrate with signal-averaged electrocardiography (SAECG).

Methods

Between April 2015 and February 2018, we recruited 125 consecutive patients with embolic stroke of undetermined source (ESUS) and 125 patients with paroxysmal atrial fibrillation (AF) patients as control. All participants underwent P wave SAECG at baseline and ESUS patients were followed up with ECG and Holter ECG, at baseline, 3, 6, and 12 months after discharge, and every 12 months thereafter.

Results

In the ESUS group (69 males, 68.4±12.1 years), 32 (25.6%) patients were diagnosed with SCAF during follow-up. There were no significant differences between both groups in terms of P wave duration [PWD] (ESUS vs. AF, P=0.321). PWD demonstrated a significant predictive efficacy for SCAF detection during follow-up (C-index of standard PWD=0.657, 95% confidence interval (CI) 0.552–0.761, P=0.008).

Stroke recurrence occurred in 22 patients (17.6%) and was significantly associated with PWD but not SCAF (odds ratio 2.756, 95% CI 1.061–7.161, P=0.037).

Conclusion

PWD, an ECG biomarker associated with atrial substrate directly contributes to AF and ESUS, is useful for predicting SCAF. The potential for using this simple ECG biomarker for screening for SCAF amongst ESUS patients merits further exploration.

Dynamic predictive model for postoperative nausea and vomiting for intravenous fentanyl patient-controlled analgesia

Postoperative nausea and vomiting is the most common side-effect of opioid-based intravenous patient-controlled analgesia. Apfel's simplified risk score is popular but it has some limitations. We developed and validated a dynamic predictive model for nausea or vomiting up to 48 postoperative hours, available as an online web application. Fentanyl was used by 22,144 adult patients for analgesia after non-cardiac surgery under general anaesthesia: we randomly divided them into development (80%) and validation (20%) cohorts, repeated 100 times. We used linear discriminant analysis to select variables for multivariate logistic regression. The incidences of postoperative nausea or vomiting were: 0-48 h, 5691/22,144 (26%); 0-6 h, 2749/22,144 (12%); 6-12 h, 2687/22,144 (12%); 12-18 h, 2624/22,144 (12%); 18-24 h, 1884/22,144 (9%); and 24-48 h, 1082/22,144 (5%). The median (95%CI) area under the receiver operating characteristic curve was 0.72 (0.71-0.73) up to 48 postoperative hours compared with 0.65 (0.64-0.66) for the Apfel model, p < 0.001. The equivalent areas for 0-6 h, 6-12 h, 12-18 h, 18-24 h and 24-48 h were: 0.70 (0.69-0.72); 0.71 (0.69-0.73); 0.69 (0.68-0.71); 0.70 (0.67-0.72); and 0.69 (0.66-0.71), respectively. Our web application allows clinicians to calculate incidences of nausea and vomiting in patients receiving intravenous fentanyl for patient-controlled analgesia.

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.

Direct Observation of Proton-Neutron Short-Range Correlation Dominance in Heavy Nuclei

We measured the triple coincidence A(e,e^{'}np) and A(e,e^{'}pp) reactions on carbon, aluminum, iron, and lead targets at Q^{2}>1.5  (GeV/c)^{2}, x_{B}>1.1 and missing momentum >400  MeV/c. This was the first direct measurement of both proton-proton (pp) and neutron-proton (np) short-range correlated (SRC) pair knockout from heavy asymmetric nuclei. For all measured nuclei, the average proton-proton (pp) to neutron-proton (np) reduced cross-section ratio is about 6%, in agreement with previous indirect measurements. Correcting for single-charge exchange effects decreased the SRC pairs ratio to ∼3%, which is lower than previous results. Comparisons to theoretical generalized contact formalism (GCF) cross-section calculations show good agreement using both phenomenological and chiral nucleon-nucleon potentials, favoring a lower pp to np pair ratio. The ability of the GCF calculation to describe the experimental data using either phenomenological or chiral potentials suggests possible reduction of scale and scheme dependence in cross-section ratios. Our results also support the high-resolution description of high-momentum states being predominantly due to nucleons in SRC pairs.

Abstract P3-08-12: PIK3CA mutations in breast cancer: Mutational landscape and clinical implications in ER+/HER2- subtype

Introduction: PIK3CA mutation is one of the most frequent genomic alterations in breast cancer. We evaluated PIK3CA mutational status including spatial and temporal heterogeneity, clinical characteristics and prognostic impact focused on ER+/HER2- subtype.

Methods: We performed targeted ultra-deep sequencing (CancerSCAN™) of breast cancer tissue in a prospective cohort. Burden of disease was assessed by metabolic tumor volume(MTV) in 18F-FDG-PET scan. Association with clinical characteristics or survival were tested in ER+/HER2- subtype, using Chi square test or Kaplan-Meier method.

Results: PIK3CA analyses were performed in 1274 breast cancer specimens from 1091 patients. 957 patients had early breast cancer. PIK3CA alterations were found in 397 patients(36.3%), and frequency of PIK3CA mutation was significantly lower in triple negative breast cancer(19.0%), compared with 40.4% in ER+/HER2-, 40.9% in ER+/HER2+, and 45.2% in ER-/HER2+ subtype(p&lt;0.0001). 158 patients had more than two biopsies. Among 92 patients with second biopsy within one month, 11%(10/92) had spatial heterogeneity of PIK3CA mutation. After neoadjuvant chemotherapy, 10%(3/30) of patients had change of PIK3CA mutational status. Serial biopsy at time of recurrence revealed loss or gain of PIK3CA mutation in 10 out of 59 patients (17%). In ER+/HER2- subtype, PIK3CA had a trend toward longer distant disease free survival without statistical significance. In patients with stage IV ER+/HER2- disease, PIK3CA hotspot mutations were associated with significant longer overall survival(OS) (71.0 vs. 37.8 months, p=0.048) and better progression free survival(PFS) at 1st line palliative treatment (37.7 vs. 9.4 months, p = 0.0004). Frequency of symptomatic recurrence, recurrence as oligometastases, and specific metastatic sites were not associated with PIK3CA mutational status, except that bone metastases at first distant metastases was less prevalent in patients with PIK3CA hotspot mutations(35.6% vs. 53.8% in PIK3CA wt, p=0.048). Metabolic tumor volume(MTV) at time of first distant metastases was not associated with presence of PIK3CA mutation.

Conclusion: We observed variations in PIK3CA mutational status in more than 10% of patients with &gt;1 repeated biopsy. In stage IV ER+/HER2- disease, PIK3CA hotspot mutation seemed to be associated with longer PFS and OS, however metabolic tumor burden was not associated with PIK3CA alterations.

Citation Format: Ahn HK, Park S, Hyun SH, Park K, Lee E, Kim J-Y, Nam SJ, Kim SW, Lee JE, Lee SK, Yu JH, Ahn JS, Im Y-H, Park YH. PIK3CA mutations in breast cancer: Mutational landscape and clinical implications in ER+/HER2- subtype [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 P3-08-12.

Pan-Asian adapted Clinical Practice Guidelines for the management of patients with metastatic non-small-cell lung cancer: a CSCO-ESMO initiative endorsed by JSMO, KSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of metastatic non-small-cell lung cancer (NSCLC) was published in 2016. At the ESMO Asia Meeting in November 2017 it was decided by both ESMO and the Chinese Society of Clinical Oncology (CSCO) to convene a special guidelines meeting immediately after the Chinese Thoracic Oncology Group Annual Meeting 2018, in Guangzhou, China. The aim was to adapt the ESMO 2016 guidelines to take into account the ethnic differences associated with the treatment of metastatic NSCLC cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with metastatic NSCLC representing the oncological societies of China (CSCO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and was independent of both the current treatment practices and the drug availability and reimbursement situations in the six participating Asian countries. During the review process, the updated ESMO 2018 Clinical Practice Guidelines for metastatic NSCLC were released and were also considered, during the final stages of the development of the Pan-Asian adapted Clinical Practice Guidelines.

CXCR3 ligands in pleural fluid as markers for the diagnosis of tuberculous pleural effusion

SETTING

A tertiary care academic medical centre.

OBJECTIVE

To evaluate the clinical usefulness of C-X-C motif chemokine receptor 3 (CXCR3) ligands in tuberculous pleural effusion (TPE).

DESIGN

We recruited 336 patients with pleural effusion due to various causes. Concentrations of interferon-gamma (IFN-γ) and the CXCR3 ligands CXCL9 and CXCL11 were determined using enzyme immunoassays; adenosine deaminase (ADA) activity was measured in pleural fluid and serum.

RESULTS

TPE was diagnosed in 106 patients. Non-TB conditions included lung cancer (n = 95), para-pneumonic effusion (n = 52), non-lung malignancy (n = 30), other exudate (n = 24) and transudate (n = 29) disorders. All marker levels in serum samples and pleural fluid were significantly higher in the TPE group. Analyses of receiver operating characteristic curves for differentiating TPE from non-TB effusions produced the following results for the area under the curve (AUC) for CXCL9, CXCL11, IFN-γ and ADA, respectively: 0.982, 0.952, 0.982, and 0.952. Marker AUCs in lymphocytic exudates were also high. Combining the levels of CXCL9, IFN-γ and ADA in pleural fluid improved the diagnostic performance. Serum levels of CXCL9 had the highest AUC (0.848) for diagnosing TPE.

CONCLUSION

Levels of CXR3 ligands in pleural effusion are useful for diagnosing TPE.

OncotypeDX Recurrence Score Does Not Predict Nodal Burden in Clinically Node Negative Breast Cancer Patients

BACKGROUND

OncotypeDX recurrence score (RS)^® has been found to predict recurrence and disease-free survival in patients with node negative breast cancer. Whether RS is useful in guiding locoregional therapy decisions is unclear. We sought to evaluate the relationship between RS and lymph node burden.

METHODS

Patients with invasive breast cancer who underwent sentinel lymph node dissection from 2010 to 2015 were identified from a prospectively maintained database. Patients were excluded if they were clinically node positive or if they received neoadjuvant chemotherapy. RS was classified as low (< 18), intermediate (18-30), or high (> 30). The association between RS, lymph node burden, and disease recurrence was evaluated. Statistical analyses were performed in R version 3.4.0; p < 0.05 was considered significant.

RESULTS

A positive SLN was found in 168 (15%) of 1121 patients. Completion axillary lymph node dissection was performed in 84 (50%) of SLN-positive patients. The remaining 84 (50%) patients had one to two positive SLNs and did not undergo further axillary surgery. RS was low in 58.5%, intermediate in 32.6%, and high in 8.9%. RS was not associated with a positive SLN, number of positive nodes, maximum node metastasis size, or extranodal extension. The median follow-up was 23 months. High RS was not associated with locoregional recurrence (p = 0.07) but was significantly associated with distant recurrence (p = 0.0015).

CONCLUSIONS

OncotypeDX RS is not associated with nodal burden in women with clinically node-negative breast cancer, suggesting that RS is not useful to guide decisions regarding extent of axillary surgery for these patients.