M. Pocard

Proof of prometastatic niche induction by hepatic stellate cells

BACKGROUNDnAn interaction between tumor cells and the microenvironment, as well as the development of angiogenesis, are required to form liver metastases (LMs).nnnMATERIAL AND METHODSnImmunofluorescence detection of α-smooth muscle actin, desmin, Ki67, laminin, and CD31 was used to analyze the kinetics of tumor angiogenesis determinants, especially the contribution of hepatic stellate cells (HSCs) to angiogenesis in hepatic metastasis produced by intrasplenically injected LS174 colorectal cancer cells. Immunostaining was performed at various times (days 9, 14, 28, and 39).nnnRESULTSnAt the earliest stage, micrometastases consisted of proliferating cancer cells, a well-organized network of activated HSCs and laminin deposits. No vascular network was observed. As the LMs grew in size, an organized vascular network appeared; the laminin network colocalized with CD31 immunostaining. At the later stages, all the immunostained markers became peripheral as a central necrosis developed. Purified activated HSCs isolated from transgenic mice livers developing hepatocellular carcinoma secreted laminin and showed enhanced human umbilical vein EC network formation in a Matrigel assay. In a coinjection LM experiment, activated HSCs enhanced the metastatic process. Moreover, colorectal LMs from six patients were analyzed, and a pattern of marker distribution similar to the coinjection experiment was found in human LMs.nnnCONCLUSIONSnFor the first time, our results show that HSCs play a crucial role in organizing and accelerating the progression of metastasis in modulating the prometastatic niche, interacting with colorectal cancer cell recruitment, and the organization of angiogenesis during colorectal LM development. Therefore, HSCs may be an early therapeutic target in colorectal cancer therapies.

Diffusion-weighted magnetic resonance imaging in colorectal cancer

Magnetic resonance imaging (MRI) plays now a major role in patients with colorectal cancer regarding tumor staging, surgical planning, therapeutic decision, assessment of tumor response to chemoradiotherapy and surveillance of rectal cancer, and detection and characterization of liver or peritoneal metastasis of colorectal cancers. Diffusion-weighted MRI (DW-MRI) is a functional imaging tool that is now part of the standard MRI protocol for the investigation of patients with colorectal cancer. DW-MRI reflects micro-displacements of water molecules in tissues and conveys high degrees of accuracy to discriminate between benign and malignant colorectal conditions. Thus, in addition to morphological imaging, DW-MRI has an important role to accurately detect colorectal neoplasms and peritoneal implants, to differentiate benign focal liver lesions from metastases and to detect tumor relapse within fibrotic changes. This review provides a comprehensive overview of basic principles, clinical applications and future trends of DW-MRI in colorectal cancers.

Multidisciplinary Management of Gastrointestinal Fibrotic Stenosis in Crohn’s Disease

Crohn’s disease (CD) is a chronic inflammatory bowel disease that can involve virtually any part of the gastrointestinal tract. CD complications are the main indications for surgery. A large proportion of these interventions are due to stricturing disease. Although immunosuppressive treatments have been used more frequently during the last 25xa0years, there is no significant decrease in the need for surgery in patients with CD. Unfortunately, surgery is not curative, as the disease ultimately reoccurs in a substantial subset of patients. To best identify the patients who will require a specific treatment and to plane the most appropriate therapeutic approach, it is important to precisely define the type, the size, and the location of CD stenosis. Diagnostic approaches aim to distinguish fibrotic from inflammatory strictures. Medical therapy is required for inflammatory stenosis. Mechanical treatments are required when fibrotic CD strictures are symptomatic. The choice between endoscopic balloon dilation, stricturoplasty, and laparoscopic or open surgery is based on the presence of perforating complications, the remaining length of small bowel, and the number and length of strictures. The non-hierarchical decision-making process for the treatment of fibrotic CD therefore requires multidisciplinary clinical rounds with radiologists, gastroenterologists, interventional endoscopists, and surgeons.

Anti-TNFα therapy early improves hemodynamics in local intestinal and extraintestinal circulations in active Crohn's disease

BACKGROUND AND AIMSnActive Crohns disease affects intestine but may alter other locations as eyes vasculature. Previous studies provide evidence of elevated blood flow velocities (BFv) and volume (BFV) in superior mesenteric artery (SMA). We prospectively studied hemodynamics in feeding arteries of bowel and eyes before and 2 weeks after treatment induction with anti-TNFα.nnnMETHODSnFifteen patients (5 females, 10 males, 35.4 ± 9.0 years, mean ± SD) with active Crohns disease for 7.5 ± 7.7 years were enrolled. Ultrasound imaging was performed before and 2 weeks after treatment in SMA and retrobulbar arteries: central retinal (CRA), temporal posterior ciliary (TPCA) and ophthalmic (OA) arteries. Serum markers of inflammation (CRP and fibrinogen), arterial blood pressures (ABP) and skin flow-mediated dilation (sFMD) were measured and patients were compared to 10 control age- and sex-matched subjects.nnnRESULTSnBefore treatment, CRP and fibrinogen plasma concentrations, SMA BFV (339 ± 100 mL/min) were higher in patients than in controls by 8.5-fold (p<0.001), 1.4-fold (p<0.01) and 1.5-fold, respectively (p<0.01). BFv in CRA (3.5 ± 0.7 cm/s) and TPCA (4.4 ± 1.0 cm/s), sFMD (371 ± 469%) were significantly lower than in controls by 83%, 73% and 52% respectively (p<0.05). Two weeks after treatment, CRP and fibrinogen decreased, SMA BFV was normalized (230 ± 39L/min, p<0.01), BFv in CRA, TPCA and OA increased respectively to 4.0 ± 1.1 (p<0.05), 5.2 ± 1.4 (p<0.001), 8.9 ± 3 cm/s (p<0.05). ABP and sFMD remained unchanged.nnnCONCLUSIONSnIn active Crohns disease, a first anti-TNFα administration rapidly normalized concomitantly plasma inflammatory markers and blood-flows in the mesenteric and retrobulbar arteries without affecting blood pressure and endothelial function.

Acute colonic diverticulitis: an update on clinical classification and management with MDCT correlation

Currently, the most commonly used classification of acute colonic diverticulitis (ACD) is the modified Hinchey classification, which corresponds to a slightly more complex classification by comparison with the original description. This modified classification allows to categorize patients with ACD into four major categories (I, II, III, IV) and two additional subcategories (Ia and Ib), depending on the severity of the disease. Several studies have clearly demonstrated the impact of this classification for determining the best therapeutic approach and predicting perioperative complications for patients who need surgery. This review provides an update on the classification of ACD along with a special emphasis on the corresponding MDCT features of the different categories and subcategories. This modified Hinchey classification should be known by emergency physicians, radiologists, and surgeons in order to improve patient care and management because each category has a specific therapeutic approach.

Gastrointestinal stenting: Current status and imaging features

The use of stents in the gastrointestinal tract has been subjected to major changes. Initially, the use of stents was restricted to malignant strictures in patients with metastatic disease. But thanks to reduction of the morbidity and mortality rates, they are now used with curative intention and in patients with benign diseases after careful selection. However, for patients presenting with colon obstruction due to an advanced colon carcinoma, the mortality and morbidity are still high. The purpose of this review is to provide an overview of indications, techniques and further developments of the stents in the gastrointestinal tract and to highlight the predominant role of multidetector row computed tomography (MDCT) in the detection of potential complications.

What is the established contribution of laparoscopy in the treatment of rectal cancer

The results of laparoscopic treatment of rectal cancer have been evaluated in several randomized trials. Still, the validity of this approach remains controversial because of concerns regarding its oncological safety. In this review, oncological results of laparoscopic rectal resection were similar to those of laparotomy, with no observed survival difference. Conversion from laparoscopy to laparotomy seemed to be associated with worse oncological results and an increased post-operative morbidity including nervous sequelae. Intra-operative blood loss was significantly reduced with the laparoscopic approach, but post-operative morbidity was not different. Post-operative pain and length of hospital stay were decreased by the laparoscopic approach, and short-term quality of life was improved. There was no demonstration of significant reduction in late morbidity such as incisional hernia and bowel adhesions.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei of appendicular and extra-appendicular origin: Treatment of appendicular and extra-appendicular pseudomyxoma peritonei

The prognostic value of the primary neoplasm responsible for pseudomyxoma peritonei (PMP) remains poorly studied. The aim of this study was to determine the prognosis for patients with extra‐appendicular PMP (EA‐PMP) treated optimally with complete cytoreductive surgery (CCRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

Prediction of Resectability in Pseudomyxoma Peritonei with a New CT Score

BackgroundCurative treatment of pseudomyxoma peritonei (PMP) is complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC).ObjectiveThe aim of this study was to build and evaluate a preoperative imaging score to predict resectability.Patients and methodsBetween 2007 and 2014, all PMP patients in two tertiary reference centers who underwent laparotomy with intent to undergo CRS and HIPEC were included in this study retrospectively. Thickness of tumor burden was measured on preoperative multidetector-row computed tomography (MDCT) by two radiologists blinded to surgical results in five predetermined areas. Patients were divided into two cohorts with the same resectability rate (building and validation). The performances of the scores were assessed using receiver operating characteristic (ROC) curve analyses.ResultsOverall, 126 patients were included, with compete CRS being achieved in 91/126 patients (72.2%). Two cohorts of 63 patients matched by age, sex, burden of disease, resectability rate, and pathological grade were constituted. The MDCT score was the sum of the five measures, and was higher in unresectable disease [median 46.2xa0mm (range 27.9–74.6) vs. 0.0xa0mm (range 0.0–14.0), pxa0<xa00.001]. Area under the ROC curve was 0.863 (range 0.727–0.968) and 0.801 (range 0.676–0.914) in the building and validation cohorts, respectively. A threshold of 28xa0mm yielded a sensitivity, specificity, positive predictive and negative predictive value of 94, 81, 81 and 94% in the building cohort, and 80, 68, 59 and 85% in the validation cohort, respectively. Using our score, overall and disease-free survival were increased in the group classified as resectable.ConclusionA simple preoperative MDCT score measuring tumor burden in the perihepatic region is able to predict resectability and survival of PMP patients.

Small bowel volvulus due to torsion of pedunculated uterine leiomyoma: CT findings.

Torsion of a uterine leiomyoma is a rare complication that can be life threatening because of ischemia or necrosis. This condition may also lead to gastrointestinal complications such as obstruction or, more rarely, small bowel volvulus. Its diagnosis is difficult and can be facilitated with the use of computed tomography or magnetic resonance imaging. Treatment is based on emergency surgical resection of the twisted uterine leiomyoma and detorsion of the small bowel volvulus.