Malignant behavior of a well­differentiated digestive neuroendocrine tumor with peritoneal carcinomatosis: A case report.

Neuroendocrine neoplasms (NENs) are a heterogenous group of tumors, arising from enterochromaffin cells, with different biological and clinical characteristics. Well-differentiated Grade 1 (G1) small intestinal NENs are often characterized by a slow progression rate and a good prognosis. Peritoneal carcinomatosis of a G1 digestive NEN is not a very common finding, and thus there is little published evidence regarding its progression and management. The complex, multistage interplay between the peritoneum and the metastasizing neuroendocrine cells is not well understood, and a reliable predictive tool to identify these patients earlier in their disease course is lacking. The present study describes the case of a 68-year-old woman presenting with an oligosymptomatic, stage IV, small intestinal G1 NEN (pTxpN1pM1) with synchronous liver metastases, multifocal mesenteric tumor deposits and a low Ki67 labeling index (1%). Over a period of 15 months, the patient developed rapidly progressive peritoneal metastatic disease with repetitive self-limiting obstructive symptoms and eventually succumbed to her illness. The present case report discusses the potential relationship between low-grade NEN, location of the primary tumor and the metastatic site, and also speculates on the role of the underlying subcellular mechanisms, specific micro-environment, spreading modalities and therapeutic strategy.

Evolution of laparoscopic left lateral sectionectomy without the Pringle maneuver: through resection of benign and malignant tumors to living liver donation.

BACKGROUND: Laparoscopic left lateral sectionectomy (LLS) has gained popularity in its use for benign and malignant tumors. This report describes the evolution of the authors' experience using laparoscopic LLS for different indications including living liver donation. METHODS: Between January 2004 and January 2009, 37 consecutive patients underwent laparoscopic LLS for benign, primary, and metastatic liver diseases, and for one case of living liver donation. Resection of malignant tumors was indicated for 19 (51%) of the 37 patients. RESULTS: All but three patients (deceased due to metastatic cancer disease) are alive and well after a median follow-up period of 20 months (range, 8-46 months). Liver cell adenomas (72%) were the main indication among benign tumors, and colorectal liver metastases (84%) were the first indication of malignancy. One case of live liver donation was performed. Whereas 16 patients (43%) had undergone a previous abdominal surgery, 3 patients (8%) had LLS combined with bowel resection. The median operation time was of 195 min (range, 115-300 min), and the median blood loss was of 50 ml (range, 0-500 ml). Mild to severe steatosis was noted in 7 patients (19%) and aspecific portal inflammation in 11 patients (30%). A median free margin of 5 mm (range, 5-27 mm) was achieved for all cancer patients. The overall recurrence rate for colorectal liver metastases was of 44% (7 patients), but none recurred at the surgical margin. No conversion to laparotomy was recorded, and the overall morbidity rate was 8.1% (1 grade 1 and 2 grade 2 complications). The median hospital stay was 6 days (range, 2-10 days). CONCLUSIONS: Laparoscopic LLS without portal clamping can be performed safely for cases of benign and malignant liver disease with minimal blood loss and overall morbidity, free resection margins, and a favorable outcome. As the ultimate step of the learning curve, laparoscopic LLS could be routinely proposed, potentially increasing the donor pool for living-related liver transplantation.

Immunohistochemistry as a screening tool for NTRK gene fusions: results of a first Belgian ring trial.

A Belgian ring trial for pan-TRK immunohistochemistry (IHC) staining was organised to harmonise pan-TRK IHC staining protocols and interpretation. As a reference method, the VENTANA pan-TRK Assay (clone EPR17341) on the Benchmark Ultra platform was selected. Six samples were selected: 2 negative, 2 fusion positive and 2 samples with wild-type endogenous TRK expression. Each participating laboratory stained the slides using their routine pan-TRK IHC and reported their results. In addition, they were asked to return one TRK-stained slide from each case. The coordinating lab evaluated these slides, compared them with the reference method and scored them. Two clones were used during the ring trial: A7H6R (Cell Signaling) and EPR17341 (Abcam/Ventana). Seven protocols achieved a sufficient performance mark, and three labs were advised to further optimise the protocol. Interpretation of pan-TRK IHC proved to be challenging in cases with physiological TRK expression. In addition, depending on the NTRK fusion partner, the staining can vary strongly in both intensity and staining pattern. Labs using the Ventana ready-to-use system based on the EPR17341 clone and using the recommended protocol settings scored best. However, given some small optimisation, all labs scored well on the technical staining and the succeeding evaluation.

Absence of placental growth factor blocks dextran sodium sulfate-induced colonic mucosal angiogenesis, increases mucosal hypoxia and aggravates acute colonic injury.

Angiogenesis has recently been described as a component of inflammatory bowel disease. Placental growth factor (PlGF), a vascular endothelial growth factor (VEGF) homologue, establishes its angiogenic capacity under pathophysiological conditions. We investigated the function of PlGF in experimental models of acute colitis. Acute colonic damage was induced in PlGF knock-out ((-/-)) mice and PlGF wild-type ((+/+)) mice by dextran sodium sulfate (DSS) and trinitrobenzenesulfonic acid (TNBS). The concentrations of PlGF and VEGF were measured in distal colonic lysates using an enzyme-linked immunosorbent assay. Colonic injury was evaluated by assessing colon length, colonocyte apoptosis (by terminal dUTP nick-end labeling), colonic cytokine production and histological score. Infiltration of polymorphonuclear cells was determined by assaying myeloperoxidase (MPO) activity. In a separate experiment, recombinant PlGF was administered to PlGF(-/-) mice by adenoviral transfer before DSS administration. Mucosal vascularization was quantified by computerized morphometric analysis of CD31-stained distal colonic sections. Colonic mucosal hypoxia was visualized by pimonidazole staining. Both VEGF and PlGF were upregulated during acute colitis. In addition, compared with PlGF(+/+) controls, PlGF(-/-) mice showed a significant increase in weight loss and colonic shortening during both DSS and TNBS colitis. This correlated with enhanced colonocyte apoptosis, elevated colonic cytokine levels and increased histological damage score, but not with enhanced inflammatory cell infiltration (MPO activity). The increased morbidity of PlGF(-/-) mice during DSS colitis was preventable by adenovirus (Ad)-mediated overexpression of PlGF. After the administration of DSS, strongly reduced mucosal angiogenesis was observed in PlGF(-/-) mice compared with PlGF(+/+) mice. This was associated with an early increase in intestinal epithelial pimonidazole accumulation in PlGF(-/-) mice, suggesting a function of enhanced epithelial hypoxia in the observed differences between the two groups. In summary, our data show that the absence of PlGF strongly inhibits mucosal intestinal angiogenesis in acute colitis, which is associated with an early increase in intestinal epithelial hypoxia and aggravation of the course of the disease.

Alteration of N-glycome in diethylnitrosamine-induced hepatocellular carcinoma mice: a non-invasive monitoring tool for liver cancer.

BACKGROUND AND AIMS: There is a demand for serum markers that can routinely assess the progression of liver cancer. DENA (diethylnitrosamine), a hepatocarcinogen, is commonly used in an experimental mouse model to induce liver cancer that closely mimics a subclass of human hepatocellular carcinoma (HCC). However, blood monitoring of the progression of HCC in mouse model has not yet been achieved. In this report, we studied glycomics during the development of mouse HCC induced by DENA. METHODS: Mouse HCC was induced by DENA. Serum N-glycans were profiled using the sequencer assisted-Fluorophore-assisted carbohydrate electrophoresis technique developed in our laboratory. Possible alteration in the transcription of genes relevant to the synthesis of the changed glycans was analysed by real-time polymerase chain reaction. RESULTS: In comparison with the control mice that received the same volume of saline, a tri-antennary glycan (peak 8) and a biantennary glycan (peak 4) in serum total glycans of DENA mice increased gradually but significantly during progression of liver cancer, whereas a core-fucosylated biantennary glycan (peak 6) decreased. Expression of alpha-1,6-fucosyltransferase 8 (Fut8), which is responsible for core fucosylation, decreased in the liver of DENA mice compared with that of age-matched control mice. Likewise, the expression level of Mgat4a, which is responsible for tri-antennary, significantly increased in the liver of DENA mice (P<0.001). CONCLUSIONS: The changes of N-glycan levels in the serum could be used as a biomarker to monitor the progress of HCC and to follow up the treatment of liver tumours in this DENA mouse model.

Monoclonal antibody 14C5 targets integrin alphavbeta5.

This study identifies and characterizes the antigen recognized by monoclonal antibody (mAb) 14C5. We compared the expression of antigen 14C5 with the expression of eight integrin subunits (alpha1, alpha2, alpha3, alphav, beta1, beta2, beta3, and beta4) and three integrin heterodimers (alphavbeta3, alphavbeta5, and alpha5beta1) by flow cytometry. Antigen 14C5 showed a similar expression to alphavbeta5 in eight different epithelial cancer cell lines (A549, A2058, C32, Capan-2, Colo16, HT-1080, HT-29, and SKBR-3). Specific binding of P1F6, an anti-alphavbeta5 specific antibody, was blocked by mAb 14C5. After transient expression of alphavbeta5 in 14C5-negative Colo16 cells, mAb 14C5 was able to bind a subpopulation of alphavbeta5-positive cells. We evaluated the tissue distribution of the 14C5 antigen in colon (n = 20) and lung (n = 16) cancer tissues. The colon carcinoma cells stained positive for 14C5 in 50% of tumors analyzed, whereas bronchoalveolar lung carcinoma and typical carcinoid were not positive for the antigen. More common types of non-small cell lung cancer, i.e., squamous (n = 5) and adenocarcinoma (n = 3), stained positive in 2 of 5 squamous carcinomas and in 1 of 3 investigated adenocarcinoma. Colon (95%) and lung (50%) carcinoma tissues showed extensive expression of antigen 14C5 in the stroma surrounding the tumor cells and on the membrane of the adjacent fibroblasts. We show for the first time that mAb 14C5 binds the vascular integrin alphavbeta5, suggesting that mAb 14C5 can be used as a screening agent to select colon and lung cancer patients that are eligible for anti-alphavbeta5-based therapies.

An intravital microscopic study of the hepatic microcirculation in cirrhotic mice models: relationship between fibrosis and angiogenesis.

This intravital fluorescence microscopy (IVFM) study validates cirrhotic mice models and describes the different intrahepatic alterations and the role of angiogenesis in the liver during genesis of cirrhosis. Cirrhosis was induced by subcutaneous injection of carbon tetrachloride (CCl(4)) and by common bile duct ligation (CBDL) in mice. Diameters of sinusoids, portal venules (PV), central venules (CV) and shunts were measured at different time points by IVFM. Thereafter, liver samples were taken for sirius red, CD31, Ki67, vascular endothelial growth factor (VEGF) and alpha-smooth muscle actin (alpha-SMA) evaluation by immunohistochemistry (IHC). In parallel with fibrogenesis, hepatic microcirculation was markedly disturbed in CCl(4) and CBDL mice with a significant decrease in sinusoidal diameter compared to control mice. In CCl(4) mice, CV were enlarged, with marked sinusoidal-free spaces around CV. In contrast, PV were enlarged in CBDL mice and bile lakes were observed. In both mice models, intrahepatic shunts developed gradually after induction. During genesis of cirrhosis using CD31 IHC we observed a progressive increase in the number of blood vessels within the fibrotic septa area and a progressively increase in staining by Ki67, VEGF and alpha-SMA of endothelial cells, hepatocytes and hepatic stellate cells respectively. In vivo study of the hepatic microcirculation demonstrated a totally disturbed intrahepatic architecture, with narrowing of sinusoids in both cirrhotic mice models. The diameters of CV and PV increased and large shunts, bypassing the sinusoids, were seen after both CCl(4) and CBDL induction. Thus present study shows that there is angiogenesis in the liver during cirrhogenesis, and this is probably due partially to an increased production of VEGF.

The value of laparoscopic liver surgery for solid benign hepatic tumors.

BACKGROUND: Laparoscopic liver resection (LLR) has gained wide acceptance for various liver resection procedures, mainly for benign diseases. However, only small series have been reported from a few selected centers. METHODS: Between January 2001 and January 2006, a total of 629 liver resections were performed at our institution. The indication was solid benign liver tumor in 56 (8.9%) patients. LLR was performed in 20 (35.7%) cases. Data from the LLR group were compared with those from a consecutive control group undergoing open liver surgery (OS) for similar indications in a matched-pair analysis during the same period. The pairs were matched as closely as possible for age, gender, American Society of Anesthesiologists (ASA) score, indication for resection, and type and location of the lesions. The endpoint was to investigate overall morbidity and outcome. RESULTS: All patients but one are alive and well after a mean follow-up of 35 months (range 10-60 months). Conversion laparotomy was required in two out of 20 (10%) cases for uncontrolled bleeding (one requiring temporary hemodialysis). LLR was characterized by faster time to first oral intake and shorter hospital stay compared to OS (p = 0.001 and 0.008, respectively). Incisional hernias (25%) were only recorded in the OS (p = 0.047 vs. LLR). Overall morbidity was 45% in OS versus 20% in LLR (p = 0.3). CONCLUSIONS: LLR significantly reduced time to oral intake, hospital stay, and incisional hernias compared to OS. Bleeding is a major risk and should be carefully considered when resecting benign tumors. In the hands of expert surgeons, LLR may become the gold standard for the resection of benign liver tumors located in the anterior and lateral sectors and for minor hepatic resections.

Expression of placental growth factor in regenerating livers after partial hepatectomy in the rat.

BACKGROUND/AIMS: Placental growth factor (PlGF) is known for its role in pathological conditions to protect parenchymal cells of different organs from injury, whereas its presence in the liver and its potential importance in stimulating liver regeneration has never been described. This was investigated in this study using a rat model of partial hepatectomy (PH). METHODS: The rat model of 70, 80, and 90% PH was used. Liver samples were taken peroperatively, 1 h, 1, 2, 3, and 7 days after surgery. Liver regeneration was evaluated by liver weight/body weight ratio, liver regeneration rate (%), and proliferating cell marker Ki67. The expression of PlGF, vascular endothelial growth factor (VEGF), VEGF receptor 1 (Flt-1), VEGF receptor 2 (Flk-1), and hypoxia inducible factor-1α mRNA was measured by quantitative real-time PCR and localized by immunohistochemistry. RESULTS: The mRNA expression of PlGF was upregulated immediately after PH. Compared with 70 and 80% PH groups, the 90% PH group had a significantly lower PlGF and hypoxia inducible factor-1α mRNA expression, in parallel to a delayed liver weight/body weight ratio recovery. Only little differences were observed in VEGF, Flt-1, and Flk-1 mRNA expression among the PH groups. CONCLUSION: This study shows for the first time the PlGF upregulation in regenerating livers, which is related to hypoxia stimulation and liver growth. The swift PlGF upregulation immediately after PH may indicate an important role for the PlGF/Flt-1 pathway in the early stage of liver regeneration.

Is combined 18F-fluorodeoxyglucose-positron emission tomography/computed tomography superior to positron emission tomography or computed tomography alone for diagnosis, staging and restaging of pancreatic lesions?

BACKGROUND AND STUDY AIMS: To evaluate whether combined 18F-FDG PET/CT has an additive value over 18F-FDG-PET or CT alone for diagnosis, staging and restaging of pancreatic lesions. PATIENTS AND METHODS: Forty-six consecutive patients (23 women, 23 men; median age 62.5 years) underwent FDG-PET/CT. Analysis of PET, CT and fused PET/CT images was performed by 2 readers. Patients were divided into 2 groups: diagnosis and staging of primary tumours (n=34) and restaging: screening for recurrent or progressive pancreatic cancer (n=12). Accuracy analysis was performed lesion-by-lesion and patient-by-patient. Results were correlated with histopathology or clinical follow-up. RESULTS: Ninety-five foci were identified on PET, 140 lesions on CT and 119 on PET/CT. Thirty-four lesions were defined as 'definitely pathologic' and localised in pancreas, liver, lung or bone by all 3 techniques with equal certainty. In 11 patients malignancy was ruled out with the highest certainty by PET/CT. All 3 modalities made 2 false positive diagnoses of malignancy and missed metastases or vascular ingrowth in 7 patients. The accuracy rate of PET/CT (91.2%) for diagnosis of primary pancreatic lesions is higher compared to CT (88.2%) and PET alone (82.3%). Also for locoregional staging PET/CT has a higher accuracy rate (85.3%) compared to CT (83.8%) and PET (79.4%). When used for restaging, sensitivity (90.0%) and accuracy rate (91.6%) were highest for PET and PET/CT. CT had a lower sensitivity (80.0%). CONCLUSIONS: Topographical assignment of 'spots' with high FDG uptake is superior with PET/CT compared to PET alone. Fused PET/CT has a slightly higher sensitivity and accuracy rate for diagnosis and locoregional staging of primary pancreatic lesions compared to CT alone. PET and PET/CT perform equally well in screening for recurrent or progressive pancreatic cancer, with high accuracy. Due to its unlimited access, lower radiation exposure and cost, multidetector row CT remains the imaging technique of choice for diagnosis, staging and screening for recurrent pancreatic cancer.

Effects of portal vein arterialization on liver regeneration after partial hepatectomy in the rat.

Although portal venous supply is considered essential to preserve hepatic integrity, in this study, effects of portal arterialization on liver regeneration were evaluated in a rat model of partial hepatectomy (PH). Ninety-six Lewis rats were randomly assigned to four groups of 24 rats each: PH only (group 1), PH with either venous or arterialized portal supply (groups 2 and 3, respectively), and PH without portal supply (group 4). Liver regeneration rate (LRR), 5-bromo-2-deoxyuridine (BrdU) labeling index, and liver biological characteristics were assessed on days 1, 2, 3, and 7. Compared with group 1, all tested rats had a marked body weight loss after surgery, and only rats in group 4 showed no signs of recovery on day 7. With maintained portal inflow (groups 1, 2, and 3), LRRs increased steadily to day-7 values of 89.2% +/- 11.8%, 81.4% +/- 8%, and 77.4% +/- 9.4%, respectively (P = not significant), and 24-hour peak values of BrdU labeling index were 159 +/- 26, 157 +/- 42, and 149 +/- 48, respectively (P = not significant). Conversely, rats deprived of portal supply (group 4) showed profound inhibition of these two parameters (14 +/- 13; P <.01;32.1% +/- 7.7%; P <.001, respectively). These results indicate that proper portal blood supply is essential to initiate and maintain liver regeneration after PH. With an equivalent portal inflow rate of either venous or arterial source, the hepatic regeneration response can be sustained.

Active delivery of trefoil factors by genetically modified Lactococcus lactis prevents and heals acute colitis in mice.

BACKGROUND & AIMS: Effective therapeutics for treating acute colitis, caused by disruption of the intestinal epithelial barrier, are scarce. Trefoil factors (TFF) are cytoprotective and promote epithelial wound healing and reconstitution of the gastrointestinal tract, which makes them good candidate therapeutics for acute colitis. However, orally administered TFF stick to the mucus of the small intestine and are absorbed at the cecum. METHODS: We have engineered the food-grade bacterium Lactococcus lactis to secrete bioactive murine TFF. The protective and therapeutic potentials of these TFF-secreting L. lactis were evaluated in parallel with purified TFF in the dextran sodium sulfate (DSS)-induced murine model for acute colitis and in established chronic colitis in interleukin (IL)-10(-/-) mice. Disease was evaluated by blinded macroscopic and microscopic inflammatory scores and by myeloperoxidase activity. RESULTS: Intragastric administration of TFF-secreting L. lactis led to active delivery of TFF at the mucosa of the colon and, in contrast to administration of purified TFF, proved to be very effective in prevention and healing of acute DSS-induced colitis. The in situ secreted murine TFF significantly decreased morbidity and mortality and stimulated prostaglandin-endoperoxide synthase 2 expression, which represents a major therapeutic pathway. In addition, this approach was successful in improving established chronic colitis in IL-10(-/-) mice. CONCLUSIONS: We have positively evaluated a new therapeutic approach for acute and chronic colitis that involves in situ secretion of murine TFF by orally administered L. lactis. This novel approach may lead to effective management of acute and chronic colitis and epithelial damage in humans.