Development of an Electroporation and Nanoparticle-based Therapeutic Platform for Bone Metastases.

Purpose To assess for nanopore formation in bone marrow cells after irreversible electroporation (IRE) and to evaluate the antitumoral effect of IRE, used alone or in combination with doxorubicin (DOX)-loaded superparamagnetic iron oxide (SPIO) nanoparticles (SPIO-DOX), in a VX2 rabbit tibial tumor model. Materials and Methods All experiments were approved by the institutional animal care and use committee. Five porcine vertebral bodies in one pig underwent intervention (IRE electrode placement without ablation [n = 1], nanoparticle injection only [n = 1], and nanoparticle injection followed by IRE [n = 3]). The animal was euthanized and the vertebrae were harvested and evaluated with scanning electron microscopy. Twelve rabbit VX2 tibial tumors were treated, three with IRE, three with SPIO-DOX, and six with SPIO-DOX plus IRE; five rabbit VX2 tibial tumors were untreated (control group). Dynamic T2*-weighted 4.7-T magnetic resonance (MR) images were obtained 9 days after inoculation and 2 hours and 5 days after treatment. Antitumor effect was expressed as the tumor growth ratio at T2*-weighted MR imaging and percentage necrosis at histologic examination. Mixed-effects linear models were used to analyze the data. Results Scanning electron microscopy demonstrated nanopores in bone marrow cells only after IRE (P , .01). Average volume of total tumor before treatment (503.1 mm3 ± 204.6) was not significantly different from those after treatment (P = .7). SPIO-DOX was identified as a reduction in signal intensity within the tumor on T2*-weighted images for up to 5 days after treatment and was related to the presence of iron. Average tumor growth ratios were 103.0% ± 75.8 with control treatment, 154.3% ± 79.7 with SPIO-DOX, 77% ± 30.8 with IRE, and -38.5% ± 24.8 with a combination of SPIO-DOX and IRE (P = .02). The percentage residual viable tumor in bone was significantly less for combination therapy compared with control (P = .02), SPIO-DOX (P , .001), and IRE (P = .03) treatment. The percentage residual viable tumor in soft tissue was significantly less with IRE (P = .005) and SPIO-DOX plus IRE (P = .005) than with SPIO-DOX. Conclusion IRE can induce nanopore formation in bone marrow cells. Tibial VX2 tumors treated with a combination of SPIO-DOX and IRE demonstrate enhanced antitumor effect as compared with individual treatments alone. © RSNA, 2017 Online supplemental material is available for this article.

Two Decades of ICU Utilization and Hospital Outcomes in a Comprehensive Cancer Center.

OBJECTIVE: To investigate ICU utilization and hospital outcomes of oncological patients admitted to a comprehensive cancer center. DESIGN: Observational cohort study. SETTING: The University of Texas MD Anderson Cancer Center. PATIENTS: Consecutive adults with cancer discharged over a 20-year period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The Cochran-Armitage test for trend was used to evaluate ICU utilization and hospital mortality rates by primary service over time. A negative binomial log linear regression model was fitted to the data to investigate length of stay over time. Among 387,306 adult hospitalized patients, the ICU utilization rate was 12.9%. The overall hospital mortality rate was 3.6%: 16.2% among patients with an ICU stay and 1.8% among non-ICU patients. Among those admitted to the ICU, the mean (SD) admission Sequential Organ Failure Assessment score was 6.1 (3.8) for all ICU patients: 7.3 (4.4) for medical ICU patients and 4.9 (2.8) for surgical ICU patients. Hematologic disorders were associated with the highest hospital mortality rate in ICU patients (42.8%); metastatic disease had the highest mortality rate in non-ICU patients (4.2%); sepsis, pneumonia, and other infections had the highest mortality rate for all inpatients (8.5%). CONCLUSIONS: This study provides a longitudinal view of ICU utilization rates, hospital and ICU length of stay, and severity-adjusted mortality rates. Although the data arise from a single institution, it encompasses a large number of hospital admissions over two decades and can serve as a point of comparison for future oncological studies at similar institutions. More studies of this nature are needed to determine whether consolidation of cancer care into specialized large-volume facilities may improve outcomes, while simultaneously sustaining appropriate resource utilization and reducing unnecessary healthcare costs.