Intraductal papillary mucinous neoplasms of the pancreas: clinicopathological features and long term outcome related to histopathological group

BACKGROUND/AIMS

To investigate the clinicopathological features of intraductal papillary mucinous neoplasms and evaluate the prognosis between histopathological groups.

METHODOLOGY

Retrospective review of 55 consecutive patients operated between 1991 and 2006, analysis of clinicopathological features and survival.

RESULTS

Group I comprised of 9 mild and 14 moderate dysplasias, group II of 11 carcinomas in situ and group III of 21 invasive cancers. Age, diabetes, anorexia and jaundice were significantly more frequent in group III. Thirty-two patients (58.2%) presented main duct type which was more frequently associated with invasive carcinoma. Mean tumoral size progress from group I to group III (26.1mm vs. 27.4mm vs. 32.0mm p=0.015) as the mean size of the pancreatic duct (6.7mm vs. 7.9mm vs. 11.5mm p=0.008). Median follow-up was 154 months with 5-year survival rate of 60.7 %. For group I, II and III it was 76.3 %, 100 % and 25.8 % respectively (p=0.00007). Lymph node positivity was associated with poor outcome: 44.1% vs. 0% (N0 vs. N+) (p=0.0019).

CONCLUSIONS

The prognosis of non-invasive intraductal papillary mucinous neoplasms of the pancreas is favourable. For patients with invasive cancer, nodal invasion is a factor of worst prognosis.

Pancreatic adenocarcinoma: general histological overview

In Belgium, approximately 1100 new cases of pancreatic ductal adenocarcinoma are diagnosed each year. Although in the last twenty years several advances have been registered in the field of pancreatic pathology, few therapies are efficacious, and it remains one of the deadliest of all cancers. Histological variants with a somewhat different prognosis have been recognised, and precursor lesions identified. This article reviews the histological aspects of ductal adenocarcinoma, its variants and the precursor lesions. Study and knowledge of these precursor lesions offers the best hope for treating pancreatic cancer before an incurable invasive tumour develops.

Assessment of the quality of the pathological evaluation of total mesorectal excision specimens: Differences in evaluation between local pathologists and a review committee in the context of an improvement project

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Background: Data on quality control of the pathologic evaluation of total mesorectal excision specimens are scarce. Differences between evaluation by local pathologists participating in PROCARE, a Belgian improvement project on rectal cancer, and a review panel were assessed. Methods: Based on photographic material and histopathology slides, a review committee of pathologists with a particular interest in colorectal pathology re-evaluated the mesorectal plane, the circumferential resection margin (CRM), the tumour differentiation grade, the (y)pT stage and the tumour regression grade (according to Dworak) in 444 cases (354 low anterior resection and 90 abdomino-perineal resection specimens). Results: The surgical plane was reported in 89% and the CRM in 88% of cases by the local pathologist. The median number of lymph nodes harvested in patients undergoing long-course neoadjuvant radiochemotherapy was 11, whereas this was 14 in the other patients. The review committee downgraded the surgical plane of 17% of patients from (intra)mesorectal to intramuscular, and upgraded it in 27% from intramuscular to (intra)mesorectal. Tumour differentiation grade, T stage and tumour regression grade differed between local pathologists and review committee in 15%, 10% and 38%, respectively. T stage was upgraded in 8% of cases, mainly from T2 to T3. Tumour regression was judged by the review panel to be less advanced in 15% of cases. Conclusions: Acknowledging some shortcomings (comparison between a photographical evaluation and an evaluation on a fresh specimen), this study gives a realistic view of clinical practice. There are differences in interpretation with regard to macroscopic and microscopic analysis of TME specimens. These findings indicate a need for more objective and reproducible criteria in histopathology. Being aware of this is a first step for improvement.

Various nanostructures on macroscopically large areas prepared by tunable ion-swelling

Various nanostructures were fabricated by ion irradiation on large area (100) Si surfaces covered by colloidal Langmuir-Blodgett films as nanolithographic masks. The ordered structure of the Langmuir-Blodgett monolayer composed from spherical Stöber silica particles of 200 nm and 450 nm diameter offer the possibility to form local surface swelling patterns during the ion bombardment step. Utilizing the dependence of the surface morphology on the irradiation parameters the tunability of nanostructuring was studied for 40 keV Ar+ and 500 keV Xe2+ ions. We show that the periodicity of the resulted surface pattern is determined by the size of the masking particles, while the height of nanostructures can be tuned by the ion fluence. The quality of projection of the nanomask contours to the substrate-the contrast of masking-can be set by choosing appropriate ion energy, thereby determining the curvature of the surface pattern. Moreover, deformation of the nanomask due to ion-nanoparticle interactions should be taken into account since these effects can be also utilized for tailoring various structures. The silica masking layers before and after ion irradiation and the resulting Si surface patterns were investigated by field emission scanning electron microscopy and atomic force microscopy analysis.

Antagonism of the antithrombotic and anti-atherosclerotic actions of aspirin by rofecoxib in the cholesterol-fed rabbit

BACKGROUND AND PURPOSE

Most patients at elevated cardiovascular risk receive long-term aspirin (ASA) anti-platelet treatment. The present study specifically addresses the pharmacological interactions between selective COX-2 inhibitors and ASA and the possible consequences for the thrombotic risk during long-term treatment.

EXPERIMENTAL APPROACH

New Zealand white rabbits were fed a standard laboratory diet supplemented with 1% cholesterol (CON) for 12 weeks. Age-matched control rabbits were fed the same standard diet without addition of cholesterol (SD). Rabbits were randomly assigned to one of the following groups: rofecoxib (ROFE, 25 mg·kg⁻¹, bid), acetylsalicylic acid (ASA, 5 mg·kg⁻¹, bid) or a combination of both (ASA + ROFE). At the end of the feeding period, the severity of atherosclerotic plaque formation was assessed in the aorta. Thrombus formation was assessed in the left carotid artery using a modified Folts procedure.

KEY RESULTS

Treatment of cholesterol-fed rabbits with ASA significantly reduced plaque formation. This reduction in lesion size was not observed in animals treated with the combination of rofecoxib and ASA. In the modified Folts model, treatment with either rofecoxib or ASA increased the total blood flow above that of untreated animals. This increase was statistically significant in the case of ASA, while cotreatment with rofecoxib abolished this ASA effect completely and reduced the total flow rate to the levels seen in untreated hypercholesterolaemic controls.

CONCLUSIONS

COX-2 inhibition by rofecoxib attenuates the antithrombotic and anti-atherosclerotic effects of ASA during long-term treatment in cholesterol-fed rabbits.

Role of Ca²+-sensitive K+ currents in controlling ventricular repolarization: possible implications for future antiarrhytmic drug therapy

Normal heart function and repolarization of the cardiac action potential (AP) is to a high extent subjective to synchronized activity of sarcolemmal K(+) channels, expressed in both ventricular and atrial myocardium, largely contributing to regulation of the resting potential, the pacemaker activity, and the shape and duration of the AP. Clinical observations and experimental studies in cardiomyocytes and multicellular preparations provided firm evidence for the sensitivity of some major outward K+ currents and the corresponding ion channels to shifts in intracellular Ca(2+) concentration ([Ca(2+)](i)). Direct regulation via interaction between [Ca(2+ )](i) and the channel protein or indirect modulation via Ca(2+ ) signaling pathways of these currents have strong implications to mechanical and electrical performance of the heart, and its physiological adaptation to altered load. It may also lead to severe cardiac dysfunction, if [Ca(2+ )](i) handling is disturbed in a variety of pathological conditions. In this review we attempt to summarize the present state of the topic on two ubiquitous repolarizing K(+) currents (I(to1) and I(K1)) with documented Ca(2+)-sensitivity and critical significance in cellular antiarrhythmic defense, to highlight fields where clue data are missing, and discuss the apparently unsolved "mystery" of the cardiac small conductance Ca(2+ )-activated K(+ ) (SK) channels. We have collected the available information on the known novel, although usually still not enough selective inhibitors and activators of these currents justifying the need for more selective ones. Finally, we emphasize a few related therapeutical perspectives to be considered for future experimental research and particularly in pharmaceutical development.

Lean non-alcoholic fatty liver disease (Lean-NAFLD): a major cause of cryptogenic liver disease

AIMS

Non-alcoholic fatty liver disease (NAFLD) is strongly associated to obesity and type 2 diabetes, but may occur in the absence of these factors. Based on a large series of liver biopsies, we have evaluated the clinical, biochemical, metabolic and pathological characteristics of a new entity, which we refer to as "lean-NAFLD".

METHODS

Among 1,777 patients, who underwent liver biopsy for chronic liver disease, Lean-NAFLD, defined as patients with NAFLD without obesity (BMI < 30 kg/m2) and without diabetes was found in 50 of them (2.8%), being the most frequent cause (38%) of cryptogenic liver disease. Thirty-one patients from the Lean-NAFLD group were compared to 48 Obese-NAFLD patients diagnosed during the same period and 8 healthy control patients. Insulin resistance was determined using the homeostasis model assessment method.

RESULTS

In the Lean-NAFLD group as compared to the obese-NAFLD group, patients were younger : median 40 vs. 49 years, p = 0.047, with male predominance: 71 vs. 46%, p = 0.037. Fasting glucose and HbA1c were lower, as was insulin sensitivity: 1.7 vs. 3.0, p = 0.049. Blood pressure was significantly lower (p = 0.001) while triglycerides and HDL-cholesterol were similar. Although there was less inflammation (p = 0.038) and fibrosis (p = 0.029), non-alcoholic steatohepatitis and fibrosis were present in 61% and 55% of the Lean-NAFLD group, respectively. Compared to healthy controls, Lean-NAFLD were less insulin sensitive, with a insulin sensitivity index of 59 vs. 110 (p = 0.015), and more hypertriglyceridemic (p = 0.003).

CONCLUSIONS

Lean-NAFLD is a new unrecognized clinicopathological entity, a frequent cause of cryptogenic liver disease.

Quality of care indicators in rectal cancer

Quality of health care is a hot topic, especially with regard to cancer. Although rectal cancer is, in many aspects, a model oncologic entity, there seem to be substantial differences in quality of care between countries, hospitals and physicians. PROCARE, a Belgian multidisciplinary national project to improve outcome in all patients with rectum cancer, identified a set of quality of care indicators covering all aspects of the management of rectal cancer. This set should permit national and international benchmarking, i.e. comparing results from individual hospitals or teams with national and international performances with feedback to participating teams. Such comparison could indicate whether further improvement is possible and/or warranted.

Putative contribution of CD56 positive cells in cetuximab treatment efficacy in first-line metastatic colorectal cancer patients

Background

Activity of cetuximab, a chimeric monoclonal antibody targeting the epidermal growth factor receptor, is largely attributed to its direct antiproliferative and proapoptotic effects. Antibody-dependent cell-mediated cytotoxicity (ADCC) could be another possible mechanism of cetuximab antitumor effects and its specific contribution on the clinical activity of cetuximab is unknown.

Methods

We assessed immune cells infiltrate (CD56, CD68, CD3, CD4, CD8, Foxp3) in the primary tumor of metastatic colorectal cancer (mCRC) patients treated with a first-line cetuximab-based chemotherapy in the framework of prospective trials (treatment group) and in a matched group of mCRC patients who received the same chemotherapy regimen without cetuximab (control group). The relationship between intra-tumoral immune effector cells, the K-ras status and the efficacy of the treatment were investigated. We also evaluated in vitro, the ADCC activity in healthy donors and chemonaive mCRC patients and the specific contribution of CD56⁺ cells.

Results

ADCC activity against DLD1 CRC cell line is maintained in cancer patients and significantly declined after CD56⁺ cells depletion. In multivariate analysis, K-ras wild-type (HR: 4.7 (95% CI 1.8-12.3), p = 0.001) and tumor infiltrating CD56⁺ cells (HR: 2.6, (95%CI:1.14-6.0), p = 0.019) were independent favourable prognostic factors for PFS and response only in the cetuximab treatment group. By contrast CD56⁺ cells failed to predict PFS and response in the control group.

Conclusions

CD56⁺ cells, mainly NK cells, may be the major effector of ADCC related-cetuximab activity. Assessment of CD56⁺ cells infiltrate in primary colorectal adenocarcinoma may provide additional information to K-ras status in predicting response and PFS in mCRC patients treated with first-line cetuximab-based chemotherapy.

Neuroendocrine tumors of pancreas: how can we apply the 2006 TNM proposal?

BACKGROUND/AIMS

In 2006, a TNM system for foregut neuroendocrine tumors has been proposed. Our study aimed to present the management of neuroendocrine tumors of pancreas according to this classification and to highlight some of its limitations.

METHODOLOGY

Clinical, biochemical, radiological, surgical and pathological data were retrospectively collected on 22 consecutives patients, who underwent surgery for neuroendocrine tumors of pancreas between November, 1991 and September, 2005. These data were used to set the TNM.

RESULTS

After excluding 5 patients, the remaining 17 patients were analyzed. In 9 patients, with a mean age of 39 years, tumors were benign with a mean size of 1.8 cm, classed at stage I-IIa, whereas for 8 patients with a mean age of 57 years, tumors were malignant with a mean size of 6cm and were classed at stage IIb-IV. There were 3 deaths in stage IIb-IV, and none in stage I-IIa.

CONCLUSION

TNM may be considered as a useful tool for prognostic stratification, but true benign tumors need to be excluded in order to improve the classification. Size and age appeared as variables affecting malignant behavior and the prognosis.

Correlations between clinical presentations of adult trigger digits and histologic aspects of the A1 pulley

PURPOSE

We aimed to report by light microscopy the normal histology of the A1 pulley, describe the histologic abnormalities of A1 pulleys in trigger digits, and look for possible correlations between these findings and the severity of the disease.

METHODS

In a series of 104 trigger digits operated on in 80 adult patients, the A1 pulleys were removed and histologically studied. The findings were compared with 55 normal A1 pulleys obtained from fresh-frozen cadaveric specimens.

RESULTS

The normal A1 pulley was composed of 3 layers: layer I, an inner, avascular, concave unicellular or bicellular gliding layer containing cartilage-like cells; layer II, a middle layer, also avascular, characterized by spindle-shaped fibroblasts; and layer III, an outer, richly vascularized layer, continuous with the membranous tendons sheath. We used a 3-grade classification, increasing in severity, to describe the histologic abnormalities observed in trigger digit A1 pulleys. Mild abnormalities (grade 1) were those with a fibrocartilaginous gliding surface almost intact. The margin between the fibrocartilaginous and membranous portions of the pulley was well delineated. In moderate abnormalities (grade 2), the avascular fibrocartilaginous gliding surface appeared fissured and thinner. The inner layer (I) was interrupted and replaced by fibrous tissue, with fissures that did not cross through the middle layer (II). A mild vascular network hyperplasia was observed in the outer layer (III), which began to invade the fibrocartilage. In severe abnormalities (grade 3), the fibrocartilaginous gliding surface was thin, discontinuous, or even completely destroyed. The vascular network hyperplasia became excessive and reached the synovial space of the flexor tendon sheath. The histologic features were correlated with the severity of the clinical symptoms (p < .001).

CONCLUSIONS

The histologic abnormalities observed in the A1 pulley of trigger digits are characteristic and not related to inflammation. As the trigger digit worsens, the gliding surface begins to wear and is gradually replaced by a secondary invasive hyperplasia from the outer layer. These abnormalities could be caused by a modification or an increase of the mechanical stresses along the flexor tendons.

Intraductal optical coherence tomography during endoscopic retrograde cholangiopancreatography for investigation of biliary strictures

BACKGROUND AND STUDY AIMS

Optical coherence tomography (OCT) uses infrared light reflectance to produce high-resolution cross-sectional tissue images. The aim of this study was to demonstrate the feasibility of biliary intraductal OCT during endoscopic retrograde cholangiopancreatography (ERCP) and to assess the potential of the method to detect malignant biliary strictures.

PATIENTS AND METHODS

Thirty-seven patients with biliary strictures were studied during therapeutic ERCP. Malignant strictures were defined as those that demonstrated malignant cells in brushing and/or biopsy specimens, and/or endoscopic ultrasound-guided fine-needle aspiration and/or surgery. Strictures that did not have malignant cells in resected specimens and were without clinical/radiological evidence of disease progression for at least a 12-month follow-up period were considered as benign. Two OCT criteria for malignancy were considered: unrecognizable layer architecture; and presence of large, nonreflective areas compatible with tumor vessels. Sensitivity and specificity for brushings/biopsies as well as OCT criteria were calculated.

RESULTS

Nineteen patients had malignant and 16 had benign strictures. In two patients, OCT assessment could not be performed due to tight strictures. Malignancy was confirmed by biliary brushings/biopsies in 12/19 (63 %) patients. OCT revealed that two malignancy criteria were encountered in 10/19 (53 %) and at least one criterion in 15/19 (79 %) patients with malignant strictures. No patient with benign stricture met both criteria and 5/16 met one criterion (31 %). Combining brushings/biopsy with the observation of at least one OCT criterion resulted in the diagnosis of malignancy in 16/19 (84 %) patients.

CONCLUSIONS

OCT may improve the sensitivity and diagnostic accuracy of biliary brushings/biopsies alone.

Expression of galectins-1, -3 and -4 varies with strain and type of experimental colitis in mice

Galectins are increasingly the focus of biomedical research. Although they are involved at different stages in inflammation, data on galectins in colitis remain scarce. The aim of this study was to determine and compare the expression of galectins in acute and chronic experimental colitis in mice. Immunohistochemistry for galectins-1, -3 and -4 was performed on colon tissue from C57BL/6 and BALB/c mice with acute dextran sodium sulphate colitis and from 129 Sv/Ev IL-10 knock-out (IL-10(-/-)) mice. From these three mouse strains, we first detected major differences in galectin expression related to the genetic background in the control animals. With regard to inflammation, chronic colitis in IL-10(-/-) mice was associated with increased galectin-4 expression; in contrast with the two other models, no galectin-1 and -3 alterations were observed in IL-10(-/-) mice. Acute colitis in C57BL/6 and BALB/c mice showed increased galectin-3 expression in the lamina propria and the crypt epithelium, together with a decreased nuclear expression. These results suggest an involvement of galectins in the development and perpetuation of colonic inflammation and illustrate that the choice of the mouse strain for studying galectins might influence the outcome of the experiments.

Complex decongestive physiotherapy decreases capillary fragility in lipedema

Lipedema is a disproportional obesity featuring frequent hematoma formation due to even minor traumatic injuries. On the basis of clinical observations, complete decongestive physiotherapy diminishes the incidence of hematomas due to minor injuries beyond leg volume reduction. Hematoma development may be caused by altered capillary resistance (CR) or altered capillary fragility (CF). We measured capillary fragility (CF) before and after complex decongestive physiotherapy (CDP) to examine, whether CDP could reduce CF. 38 women with lipedema were included in the study. Twenty-one (21) patients were treated with CDP and 17 using exclusively moisturizers as the control group. CDP comprised once daily manual lymph drainage, intermittent pneumatic compression and multilayered short-stretch bandaging performed throughout a 5-day-course. CF was evaluated with the vacuum suction method (VSM) using Parrot's angiosterrometer in both groups. Decongestive therapy resulted in a significant reduction of the number of petechiae while no change was detected within the control group. Complete decongestive physiotherapy significantly reduced CF in patients with lipedema and this reduction may lead to reduced hematoma formation.

Expression of galectin-3 in the tumor immune response in colon cancer

The role of tumor-associated macrophages (TAMs) is controversial. Although most studies on different cancer types associate them with a poorer prognosis, interestingly in colon cancer, most articles indicate that TAMs prevent tumor development; patients with high TAMs have better prognosis and survival rate. M1-polarized macrophages produce high level of tumor necrosis factor-alpha, interleukin-1 beta or reactive oxygen species, which can effectively kill susceptible tumor cells. In contrast, M2-polarized macrophages can secrete different factors that promote tumor cell growth and survival or favor angiogenesis and tissue invasion. Considering the beneficial role of TAMs in colon cancer, we speculated that they may not display the M2 polarization commonly observed in tumor microenvironment, but rather develop M1 properties. Therefore, we used an in vitro model to analyze the effects of supernatants from M1-polarized macrophages on DLD-1 colon cancer cells. Our data indicate that the conditioned medium from LPS-activated macrophages (CM-LAM) contains a high level of granulocyte-macrophage colony-stimulating factor, interleukins-1 beta, -6, -8 and tumor necrosis factor-alpha, and that it exerts a marked growth inhibitory activity on DLD-1 cells. Prolonged exposure to CM-LAM results in cell death by apoptosis. Such exposure to CM-LAM leads to the modulation of gal-3 expression: we observed a marked downregulation of gal-3 mRNA and protein expression following CM-LAM treatment. We also describe that the knockdown of gal-3 sensitizes DLD-1 cells to CM-LAM. These data suggest an involvement of gal-3 in the response of colon cancer cells to proinflammatory stimuli, such as the conditioned medium from activated macrophages.

The galectin family and digestive disease

The soluble-type lectins or galectins constitute a family of proteins defined by shared consensus amino acid sequence and affinity for beta-galactose-containing oligosaccharides. These molecules are widely distributed in the animal kingdom; to date, 15 mammalian galectins have been described but more are likely to be discovered. These proteins are involved in many biological processes including cell-cell and cell-matrix adhesion, growth regulation, signaling, and cytokine secretion. Over the last decade, a vast amount of reports has shown the importance of several galectins in the development and progression of malignancies in the digestive tract, mainly colorectal cancers. More recent data indicate that some of these molecules are also involved in inflammatory bowel diseases. This review focuses on the current knowledge of galectin expression and putative functions in the oesophagus, stomach, small intestine, and colon. It also highlights that the rapid accumulation of research data promises future scenarios in which individual members of the galectin family and/or their ligands will be used as diagnostic and therapeutic modalities for neoplastic as well as inflammatory disorders. However, the concretization of these potential modalities requires substantial improvements in terms of standardization of galectin expression evaluation together with prospective validation of the present data.