Synchronous and metachronous colorectal liver metastases: Impact of primary tumor location on patterns of recurrence and survival after hepatic resection

Background: Considerable differences in terms of prognosis exist between the right-sided (RCC) and the left-sided colon cancer (LCC). Aim of the work: In this study, we evaluated prognostic implications of primary tumor location (PTL) among patients who underwent curative-intent hepatectomy for synchronous (SM) and metachronous (MM) colorectal liver metastases (CRLM). Methods: The study population included all consecutive patients affected by CRLM scheduled for first liver resection at three Italian oncological centers. Results: A total of 204 patients who underwent CRLM resection were included, 50% with RCC. Synchronous lesions were prevalent (n=133, 65%). Median OS was respectively 40.3 months for SM-RCC, 53.5 months for SM-LCC, 64.5 months for MM-RCC and 81.6 months for MM-LCC. Patients with MM-LCC showed an OS better than patients with SM-RCC (p=0.008) and SM-LCC (p=0.002). PTL had no influence on RFS. RCC group had less recurrences (75% vs 86.5%), though further surgery with curative-intent was possible more in LCC group (29.3% vs 32.5%). Cox proportional hazards model analysis showed that age and the presence of SM vs MM was associated with a significantly higher hazard ratio (HR) for death (HR=1.024; 95%CI=1.005-1.043; p=0.011 and HR=2.010; 95%CI=1.328-3.043; p=0.001, respectively). Conclusions: We confirmed that patients with CRLM and right-sided primary colon cancer experience worse survival after hepatic resection. The timing of metastasis has been revealed as important prognostic factor

Observations of the Optical Counterpart to XTE J1118+480 During Outburst by the ROTSE-I Telescope

The X-ray nova XTE J1118+480 exhibited two outbursts in the early part of 2000. As detected by the Rossi X-ray Timing Explorer (RXTE), the first outburst began in early January and the second began in early March. Routine imaging of the northern sky by the Robotic Optical Transient Search Experiment (ROTSE) shows the optical counterpart to XTE J1118+480 during both outbursts. These data include over 60 epochs from January to June 2000. A search of the ROTSE data archives reveal no previous optical outbursts of this source in selected data between April 1998 and January 2000. While the X-ray to optical flux ratio of XTE J1118+480 was low during both outbursts, we suggest that they were full X-ray novae and not mini-outbursts based on comparison with similar sources. The ROTSE measurements taken during the March 2000 outburst also indicate a rapid rise in the optical flux that preceded the X-ray emission measured by the RXTE by approximately 10 days. Using these results, we estimate a pre-outburst accretion disk inner truncation radius of 1.2 x 10^4 Schwarzschild radii.Comment: 9 pages, 1 table, 2 figure

The very early afterglow powered by the ultra-relativistic mildly magnetized outflows

In the Poynting Flux dominated outflow (the initial ratio of the electromagnetic energy flux to the particle energy flux $\sigma_0\gg1$) model for Gamma-ray bursts, nearly half of the internally dissipated magnetic energy is converted into the prompt $\gamma-$ray energy emission and the rest is converted into the kinetic energy of the outflow. Consequently, at the end of the $\gamma-$ray burst, $\sigma$ decreases significantly ($\sigma\sim 1$ or even smaller). We numerically investigate the very early reverse shock emission powered by such mildly magnetized outflows interacting with medium--uniform interstellar medium (ISM) or stellar wind (WIND). We show that for $\sigma\sim0.05-1$ and typical parameters of Gamma-ray bursts, both the ISM-ejecta interaction and the WIND-ejecta interaction can power very strong optical emission ($m_{\rm R}\sim 10-12{\rm th}$ magnitude or even brighter). Similar to the very early afterglow powered by the non-magnetized ejecta interacting with the external medium, the main difference between the ISM-ejecta interaction case and the WIND-ejecta interaction case is that, before the reverse shock crosses the ejecta, the R-band emission flux increases rapidly for the former, but for the latter it increases only slightly. (The abstract has been shortened). We suggest that the linear polarization detection of the early multi-wavelength afterglow is highly needed to see whether the outflows powering GRBs are magnetized or not.Comment: 8 pages, 3 figures, A&A in pres

Observation of contemporaneous optical radiation from a gamma-ray burst

The origin of gamma-ray bursts (GRBs) has been enigmatic since their discovery. The situation improved dramatically in 1997, when the rapid availability of precise coordinates for the bursts allowed the detection of faint optical and radio afterglows - optical spectra thus obtained have demonstrated conclusively that the bursts occur at cosmological distances. But, despite efforts by several groups, optical detection has not hitherto been achieved during the brief duration of a burst. Here we report the detection of bright optical emission from GRB990123 while the burst was still in progress. Our observations begin 22 seconds after the onset of the burst and show an increase in brightness by a factor of 14 during the first 25 seconds; the brightness then declines by a factor of 100, at which point (700 seconds after the burst onset) it falls below our detection threshold. The redshift of this burst, approximately 1.6, implies a peak optical luminosity of 5 times 10^{49} erg per second. Optical emission from gamma-ray bursts has been generally thought to take place at the shock fronts generated by interaction of the primary energy source with the surrounding medium, where the gamma-rays might also be produced. The lack of a significant change in the gamma-ray light curve when the optical emission develops suggests that the gamma-rays are not produced at the shock front, but closer to the site of the original explosion.Comment: 10 pages, 2 figures. Accepted for publication in Nature. For additional information see http://www.umich.edu/~rotse

Frequency of left ventricular hypertrophy in non-valvular atrial fibrillation

Left ventricular hypertrophy (LVH) is significantly related to adverse clinical outcomes in patients at high risk of cardiovascular events. In patients with atrial fibrillation (AF), data on LVH, that is, prevalence and determinants, are inconsistent mainly because of different definitions and heterogeneity of study populations. We determined echocardiographic-based LVH prevalence and clinical factors independently associated with its development in a prospective cohort of patients with non-valvular (NV) AF. From the "Atrial Fibrillation Registry for Ankle-brachial Index Prevalence Assessment: Collaborative Italian Study" (ARAPACIS) population, 1,184 patients with NVAF (mean age 72 \ub1 11 years; 56% men) with complete data to define LVH were selected. ARAPACIS is a multicenter, observational, prospective, longitudinal on-going study designed to estimate prevalence of peripheral artery disease in patients with NVAF. We found a high prevalence of LVH (52%) in patients with NVAF. Compared to those without LVH, patients with AF with LVH were older and had a higher prevalence of hypertension, diabetes, and previous myocardial infarction (MI). A higher prevalence of ankle-brachial index 640.90 was seen in patients with LVH (22 vs 17%, p = 0.0392). Patients with LVH were at significantly higher thromboembolic risk, with CHA2DS2-VASc 652 seen in 93% of LVH and in 73% of patients without LVH (p <0.05). Women with LVH had a higher prevalence of concentric hypertrophy than men (46% vs 29%, p = 0.0003). Logistic regression analysis demonstrated that female gender (odds ratio [OR] 2.80, p <0.0001), age (OR 1.03 per year, p <0.001), hypertension (OR 2.30, p <0.001), diabetes (OR 1.62, p = 0.004), and previous MI (OR 1.96, p = 0.001) were independently associated with LVH. In conclusion, patients with NVAF have a high prevalence of LVH, which is related to female gender, older age, hypertension, and previous MI. These patients are at high thromboembolic risk and deserve a holistic approach to cardiovascular prevention