Factors Affecting Local and Intra Hepatic Distant Recurrence After Surgery for Hcc: An Alternative Perspective on Microvascular Invasion and Satellitosis - A Western European Multicentre Study.

BACKGROUND: Few studies have focused on risk factors which may predict an intrahepatic local recurrence (LR) on the surgical edge rather than a distant recurrence (DR) in other liver segments after surgery for hepatocarcinoma (HCC). The purpose of this study was to assess the risk factors for both patterns of recurrence. METHODS: An international, multicentre, retrospective study was conducted by collecting data on all consecutive patients with a first diagnosis of HCC who were treated between 2010 and 2017. The presence of macrovascular invasion was an exclusion criteria. RESULTS: About 376 patients were enrolled, and, among them, 62 presented LR, while 90 had DR. Baseline characteristics were comparable between the two groups, but the DR group had a much higher rate of HCV infection (48.9% vs 29%, p 0.014) and a higher median nodule size (3.40 cm IQR 2.2-5.5 versus 3.0 cm IQR 2.0-5.0 in the LR group, p 0.025). A positive surgical margin (R1, HR 4.721; 95% CI 1.83-12.17; p 0.001) was the only independent risk factor for LR, while MVI (HR 1.837; 95% CI 1.03-3.77; p 0.039) and satellitosis (HR 2.440, 95% CI 1.43-3.77, p 0.001) were the only predictive factors for DR. CONCLUSION: MVI and satellitosis are predictive factors of intrahepatic distant recurrence, configuring a probable hallmark of advanced systemic disease, regardless of the treatment. LR has to be considered the expression of surgical failure.

[Evaluation of ischemic injury of the spinal cord following endoprosthesis implantation in the thoraco-abdominal aorta on a rat model]. / Avliação da isquémia medular após implantação de endoprótese na aorta toraco-abdominal do rato.

INTRODUCTION: Spinal cord ischemia is one of the most dreaded complication which may occur after conventional surgery of the thoraco-abdominal aorta, as well as following endoprostheses implantation. A better understanding of its pathogeny and physiopathology may lead to the introduction of means or measures for its prevention. The widespread utilization of the endovascular management of thoraco-abdominal aortic pathology stimulated the search for new alternatives to overcome the problem. MATERIAL AND METHODS: An experimental study was conducted, using Wistar-Lewis rats. Thirty-six animals were employed to assess the spinal cord consequences following the implantation of PTFE endoprosthesis in the thoraco-abdominal aorta. The endoprostheses were introduced through a distal aortotomy and advanced until the limits of the subclavian artery, down to the celiac axis. A similar group of animals underwent the conventional surgical management. To evaluate the neurologic repercussions, a sensor was placed in the spinal cord aimed at the registry of the bioelectric potentials, every two hours, until a limit of eight hours, in subgroups of six animals. Finally, the spinal cord was removed for histological examination. RESULTS AND DISCUSSION: The collected data revealed that significant ischemic alterations occurred eight hours after the implantation of the endoprostheses and that 48 hours later some signs of recovery could be observed, probably by means of collateral blood flow arising from the spinal cord itself or from branches of the thoraco-abdominal vasculature. However, it must be stressed that these results were obtained in healthy animals, with normal arteries, and that the resistance of the nervous tissues to the ischemia is certainly lower than in individuals with previous arterial pathology.

[Analysis of intrasac pressure after the implantation of endoprotheses with different diameters, in an animal model of abdominal aortic aneurysm]. / Análise da pressão do saco aneurismático após a implantação de endoproteses de diâmetros diferentes, num modelo animal em aneurismas da aorta abdominal.

PURPOSE: The effect of a plain 48-wire self-expanding flexible stent (Wallgraft Boston Scientific) on abdominal aortic aneurysms has been studied in a new animal model. We performed this study in order to analyze the mechanical properties of a bare-metal Wallgraft endoprostheses to investigate their responses to hemodynamic forces. METHODS: Aneurysms were created by interposing fusiform segments of PTFE into the infrarenal aortas of 12 Large White pigs. The pigs were assessed after 2 weeks by telemetry pressure, ultrasonography and arteriography methods. Endovascular placement of the stents, 2 weeks after aneurysm creation, was performed under arteriographic control in the half of pigs (second group of study). These pigs were assessed by telemetry pressure, ultrasonography and arteriography methods, weekly after stenting; they were then sacrificed for pathological examination. RESULTS: At 6 weeks the aneurysms in the first group were pulsatile with partial endothelialisation and no mural thrombus. Placement of the stent of different sizes in the second group was easily accomplished. Stenting resulted in an immediate reduction in wall pulsatility of all aneurysms and thrombosis of the excluded aneurysm sac occurred in three cases. In the other three cases the pulse pressure in the sac was reduced. In all cases there was a significant reduction in the maximum aneurysm diameter when measured weekly after stenting. DISCUSSION AND CONCLUSIONS: A pulsatile, non-thrombogenic aortic aneurysm model approaching human dimensions has been successfully developed for the study of endoprostheses prior to their clinical use. Endovascular placement of a plain, multiple-wire Wallgraft was associated with reductions in aneurysm pulsatility, pulse pressure within the sac and maximum aneurysm diameter over the study period. Stenting was associated with thrombosis of the excluded aneurysm sac in 50% of the cases.

[Histological evaluation of ischemic injury to the spinal cord. Experimental study in the rabbit]. / Avaliação histológica das lesões isquémicas na medula espinal. Estudo experimental no coelho.

Sometimes in clinical practice the spinal cord is subjected to a more or less prolonged period of ischemia, after which cellular lesions may occur, causing paraplegia. The purpose of this paper is to quantify morphologically the damage of the spinal cord after an induced ischemia. Seventy male adult rabbits were used. They were divided into three groups: one group was used for evaluation of spinal cord ischemia at 3 hours, the second at 12 hours and the third at 24 hours. The recovery periods ranged from 3, to 12 and 24 hours. At the end of this period, the animals were anesthetized and killed. A clinical evaluation was made using the Tarlov method and criteria. The spinal cord was subjected to a histological evaluation. The results revealed different changes according to the multiple groups of study. The authors discuss the data of the present study and compare to the reports published in the bibliography on the subject.