The Predictive Value of the Syntax Score in Patients With Chronic Coronary Artery Disease Undergoing Percutaneous Coronary Intervention or Coronary Artery Bypass Grafting: A Pilot Study

Objectives:

To evaluate the usefulness of the SYNTAX score (SS) in predicting 1-year clinical outcomes in a population of patients with chronic coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG).

Background:

Despite the proven prognostic value of the SS in patients with multivessel and/or left main (LM) CAD, its usefulness in other patient subsets remains uncertain.

Methods:

This was a prospective single centre cohort study conducted from September 2012 to November 2014 at the Nicosia General Hospital, Cyprus. Patients (n=140; 94% men and 6% women) with chronic CAD undergoing revascularization with either PCI or CABG were evaluated.

Results:

At 1-year, angina occurred in 20 patients (14.3%), myocardial infarction (MI) in 3 patients (2.1%), repeat revascularization procedures in 9 patients (6.4%) and death in 12 patients (8.6%). The SS independently predicted angina (p=0.024) but was not predictive of MI (p=0.964), death (p=0.292) or repeat revascularization (p=0.069).

Conclusion:

In this patient population, the SS predicted angina in the year following revascularization but was not predictive of MI, death or repeat revascularization.

Abstract P3-03-01: Intracranial PDX models of breast cancer metastasis

Background: Overexpression of the human epidermal growth factor receptor 2 (HER2) in breast cancer is an independent factor for development of brain metastases. Up to 37% of patients with HER2 positive disease relapse intracranially despite control of extra-cranial metastatic disease. Inability of anti-cancer agents to cross an intact blood-brain barrier (BBB) is a possible explanation for the increased incidence of brain metastases.

Subcutaneous (SQ) patient-derived xenograft (PDX) models are increasingly used for efficacy studies in drug development. However, orthotopic PDX models may confer a translational advantage as the patient tumor microenvironment is more closely mimicked. Especially when targeting brain tumors, the major impact of the BBB on drug bioavailability must be taken into consideration. The aim of this study was therefore to develop a panel of intracranial PDX models of breast cancer brain metastases for pre-clinical efficacy studies of new anticancer drugs.

Methods: SQ tumors from three different HER2 positive PDX breast cancer models designated ST340, ST1339 and ST1616B were enzymatically digested and used for intracranial stereotactic injection in nude mice. Contrast-enhanced T1- and T2-weighted Magnetic Resonance Imaging (MRI) were used to determine tumor take. Intracranial tumor growth was monitored using MRI and positron emission tomography (PET) in conjunction with the amino acid radio tracer 18F-FET.

Results: MRI confirmed tumor take in one model as early as 2 weeks after intracranial implantation. Increased 18F-FET uptake was detected in all models. MRI could be effectively used to monitor tumor growth and the corresponding 18F-FET PET images demonstrated increased 18F-FET uptake over time.

Conclusion: Three different HER2 positive intracranial PDX breast metastases models were established from low passage SQ PDX models. We suggest, that using these intracranial PDX models of brain metastases, new drugs for advanced breast cancer can be evaluated in preclinical models that more closely mimic the microenvironment and the BBB in patients. In addition, translational imaging techniques can be evaluated during preclinical testing and the potential of tracers like 18F-FET as imaging biomarkers of therapeutic response can be assessed. Together, the established SQ and orthotopic PDX models of breast cancer and brain metastases can be used as a relevant translational platform for testing of new drugs.

Citation Format: Nielsen CH, Nedergaard MK, Wick MJ, Papadopoulos K, Tolcher AW, Kjaer A. Intracranial PDX models of breast cancer metastasis. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-03-01.

Soybean oil: a potentially new intravascular perfusate

BACKGROUND

Given that micelles of lipids are colloids, the hypothesis was generated that the rapid administration of large volumes of soybean oil micelles would be an effective perfusion fluid. We also hypothesized that oxygen loading would be enhanced due to the greater solubility of oxygen in lipids compared to water.

METHODS

A 100% lethal mouse model of blood loss was used to compare the ability of soybean oil micelles to that of Ringer's lactate, blood and other fluids, with respect to raising and maintaining the blood pressure for one hour. Oxygen on- and off-loading of various concentrations of soybean oil micelles was determined using mass spectroscopy. Nitric oxide uptake by micelles was also determined in a similar fashion.

RESULTS

A 20% soybean oil emulsion was superior to Ringer's lactate in raising and maintaining blood pressure. A 20% soybean oil emulsion with 5% albumin added was superior to shed blood as well as solutions comprised of 5% albumin added to either normal saline or Ringer's lactate. There was a linear relationship between oxygen content and micelle concentration between 10% and 30%. Off-loading of oxygen from the micelles was nearly as fast as off-loading from water. Nitric oxide also loaded preferentially onto soybean oil micelles.

CONCLUSIONS

(1) Soybean oil emulsions were superior to other fluids in restoring and maintaining the blood pressure; (2) oxygen-carrying ability of soybean oil micelles exceeds that of water and follows Henry's law between 10% and 30% w/v oil content; (3) nitric oxide was carried by the micelles; (4) animals receiving soybean oil micelles did not exhibit fat embolization; (5) colloids comprised of soybean oil-containing micelles may be used to replace blood loss and may be used to deliver oxygen and other potentially therapeutic gases such as nitric oxide to tissues.