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Christophe Laurent

Publications and source records attributed to Christophe Laurent.

11 recordsLinked to original sources

Comparison of functional results and quality of life between intersphincteric resection and conventional coloanal anastomosis for low rectal cancer.

PURPOSE: The technique of intersphincteric resection permits sphincter preservation with good oncologic results in very low rectal cancer. This study aimed to investigate functional results and quality of life after intersphincteric resection compared with conventional coloanal anastomoses. METHODS: From 1990 to 2000, 170 patients underwent total mesorectal excision with coloanal anastomosis for low rectal tumors. Questionnaires were obtained from 77 patients alive without colostomy: 37 had a conventional coloanal anastomosis and 40 had intersphincteric resection. Both groups were similar according to age, gender, anastomotic stenosis, colonic pouch, anastomotic leakage, preoperative radiotherapy, and follow-up (median, 56 months). Assessment included one functional and two quality-of-life questionnaires: the SF-36 Health Status and the Fecal Incontinence Quality of Life score. RESULTS: There was no difference in stool frequency, fragmentation, urgency, dyschesia, and alimentary restriction between patients with and without intersphincteric resection. Patients with intersphincteric resection had significantly worse continence (Wexner score, 10.8 vs. 6.9; P < 0.001) and needed more antidiarrheal drugs (60 vs. 35 percent; P = 0.04) than those without. Compared with conventional coloanal anastomoses, quality of life was altered by intersphincteric resection for the subscale embarrassment ( P < 0.01) in the Fecal Incontinence Quality of Life score, whereas no difference of quality of life was observed with SF-36. CONCLUSIONS: Compared with conventional coloanal anastomoses, patients with intersphincteric resection have a higher risk of fecal incontinence and a slightly altered quality of life.

Adult↗

Long-term functional results after sphincter-saving resection for rectal cancer.

INTRODUCTION: A number of patients suffer from gastrointestinal side effects following sphincter-saving resection of the rectum. The aim of this study was to assess frequency and risk factors of long-term gastrointestinal side effects after sphincter-saving resection for rectal cancer. PATIENTS AND METHODS: Between 1980 and 1997, among 209 patients treated for rectal cancer by rectal resection and sphincter conservation, 145 who were alive without recurrence or colostomy, responded to a questionnaire. There were 85 males and 60 females with a mean age of 64 Years; the follow-up was 5.4 Years. The functional result was considered good if the number of stools per 24h was three or less with normal continence and poor if the number of stools was four or more or if fecal incontinence was present. Influence of age, gender, anastomotic height, type of sutured colon, colonic pouch, defunctioning stoma, leakage, stenosis, radiotherapy, history of irritable bowel syndrome and follow-up were analyzed. RESULTS: The mean anastomotic height was 5 cm from the anal margin. Functional results were good in 56% of patients and poor in 44%. Univariate analysis showed three variables to be significantly associated with the functional results: anastomotic height (P=0.001), radiotherapy (P=0.03) and follow-up > 24 Months (P=0.009). Multivariate analysis showed that only anastomotic height independently influenced functional results. They were good in 76%, 53% and 35% of patients for anastomoses located above 6 cm, between 6 and 3 cm, and below 3 cm from the anal margin, respectively. CONCLUSION: After sphincter-saving resection for rectal cancer, about half of patients have poor long-term functional results, the latter being related only to the anastomotic height. This suggests the need to preserve a small part of the rectum when oncologically feasible.

Adult↗

FNH-like nodules: Possible precursor lesions in patients with focal nodular hyperplasia (FNH).

BACKGROUND: The typical lesion of focal nodular hyperplasia (FNH) is a benign tumor-like mass characterized by hepatocytic nodules separated by fibrous bands. The solitary central artery with high flow and the absent portal vein give the lesions their characteristic radiological appearance. The great majority of cases seen in daily practice conform to the above description. Additional small nodules (from 1-2 up to 15-20 mm in diameter) detected by imaging techniques or on macroscopic examination may be difficult to identify as representing FNH if they lack the key features of FNH as defined in larger lesions. The aim of this study was to characterize these small nodules, and to compare their characteristics with those of typical lesions of FNH present in the same specimens. RESULTS: Eight patients underwent hepatic resections for the removal of a mass lesion ("nodule") diagnosed as: FNH (1 patient); nodules of unknown nature (5 patients); or nodules thought to be adenoma or hepatocellular carcinoma (2 patients). Six nodules out of 9 discovered by imaging techniques met histopathological criteria for the diagnosis of typical FNH, at least in parts of the nodule; 2 nodules corresponded to a minor form of FNH ("subtle FNH") and one nodule to a steatotic area. Although FNH was thought to be found in a normal or nearly normal liver, this study revealed that, in addition, there were various types of small FNH-like nodules and vascular abnormalities in the liver with typical FNH nodule. The various types of small FNH-like nodules (n = 8, diameter 2 to 20 mm) consisted of the association to various degrees of numerous and/or enlarged arteries in portal tracts or in septa, with hyperplastic foci, slight ductular reaction, and regions of sinusoidal dilatation, accompanied by thin fibrous bands. Vascular abnormalities consisted of unpaired arteries, portal tracts with arteries larger than the associated bile duct, and regions of sinusoidal dilatation. CONCLUSIONS: Although these small nodules can be considered as insufficient type or abortive forms of FNH, or adenoma, they can be precursors of the large mass lesions in which FNH was recognized and defined.

Journal Article↗

Gram-scale CCVD synthesis of double-walled carbon nanotubes.

Synthesis of clean double-walled carbon nanotubes by a catalytic chemical vapour deposition (CCVD) method is reported; the catalyst is a Mg(1 - x)Co(x)O solid solution containing additions of Mo oxide; this MgO-based catalyst can be easily removed, leading to gram-scale amounts of clean carbon nanotubes, 77% of which are double-walled carbon nanotubes.

Journal Article↗

Association of adenoma and focal nodular hyperplasia: experience of a single French academic center.

BACKGROUND: We report our experience of the simultaneous occurrence of adenoma and focal nodular hyperplasia (FNH). Liver cell adenoma together with FNH was found in five out of 30 cases of "multiple benign hepatocytic nodules" collected in our files of the Department of Pathology of the University Hospital of Bordeaux, during the last 12 years. All five cases were women on oral contraceptives. In all cases, the reason for surgery was the discovery, by imaging techniques, of an adenoma (4 cases) or of an unidentified benign tumor, possibly an adenoma. RESULTS: Four cases of FNH were discovered by imaging techniques, prior to surgery. Additional small nodules were diagnosed either during surgery or during the slicing of the specimen in 3 cases. Adenoma and the FNH cases identified by imaging techniques were confirmed as such by light microscopy. Some small nodules could not be categorized with certainty because they contained biliary structures without ductular reaction. In one case, the non-nodular liver was abnormal around the area in which there were multiple nodules: there was approximation of portal tracts with portal and hepatic venous thromboses, and portal tract remnants with arteries surrounded with a rim of fibrosis. In two cases, some large hepatic veins had thickened walls. CONCLUSIONS: The association of FNH and adenoma could be coincidental or secondary to shared causal mechanisms: a) systemic and local angiogenic abnormalities induced by oral contraceptives; b) tumor-induced growth factors; c) thrombosis and local arterio-venous shunting. A better recognition of the association of adenoma and FNH, particularly in the context of multiple nodules, could be useful in clinical practice.

Journal Article↗

Multiple telangiectatic focal nodular hyperplasia: vascular abnormalities.

The aim of this study was to look for vascular abnormalities in the liver of patients with multiple telangiectatic focal nodular hyperplasia. Four patients, all women on oral contraceptives, were included in this study. In none of the cases was the diagnosis of multiple telangiectatic focal nodular hyperplasia made preoperatively. In the nodules, the pathological aspect was quite characteristic with dilated sinusoidal areas surrounding compact areas. Compact areas comprised portal tract-like structures with vessels, mainly thickened arteries, usually amidst an inflammatory reaction. A ductular reaction of varied intensity was present in three cases. The non-nodular liver was grossly normal. However, in rare areas, there were obvious or minor vascular abnormalities looking like minimal abnormalities seen inside telangiectatic nodules. These results seem to support the concept that multiple telangiectatic focal nodular hyperplasia is a non-specific reaction to focal ischemia induced by various mechanisms such as hepatic vein thrombosis induced, perhaps, by oral contraceptives.

Adult↗

Familial liver adenomatosis associated with hepatocyte nuclear factor 1alpha inactivation.

BACKGROUND & AIMS: Germline mutations in hepatocyte nuclear factor 1alpha (TCF1/HNF-1alpha) are associated with maturity-onset diabetes of the young type 3 (MODY3), and somatic biallelic inactivations of the gene are found in hepatocellular adenomas and liver adenomatosis. This study investigated cosegregation of HNF-1alpha germline mutations with diabetes and liver adenomatosis in 2 families. METHODS: Two unrelated patients with liver adenomatosis and harboring HNF-1alpha germline and somatic mutations were studied. Subsequently, we screened 9 relatives in the 2 independent families for diabetes, hepatocellular adenomas, and HNF-1alpha germline mutations. RESULTS: In family A, a father and his son presented with an intraperitoneal hemorrhagic rupture of a liver adenomatosis without diabetes. A heterozygous R229X germline mutation was identified in HNF-1alpha in the father and his son and also in his second 27-year-old son without hepatocellular adenomas. In family B, a diagnosis of liver adenomatosis was made fortuitously in a 14-year-old girl. A heterozygous G55fsX57 germline mutation in HNF-1alpha was identified in this patient, her diabetic father, and her 2 sisters. Systematic exploration showed liver adenomatosis in the 2 sisters. Somatic inactivation of the second HNF-1alpha allele was found in liver tumors in both families. CONCLUSIONS: This study describes familial liver adenomatosis and shows the association with germline HNF-1alpha mutations in adults and children. It also highlights the importance of screening for hepatocellular adenomas, diabetes, and HNF-1alpha germline mutations in relatives of patients with liver adenomatosis. Finally, prevalence of liver adenomatosis remains to be evaluated in MODY3 subjects.

Adenoma↗

Molecular profiling of hepatocellular carcinomas (HCC) using a large-scale real-time RT-PCR approach: determination of a molecular diagnostic index.

The aim of this study was to develop and validate a molecular index for the diagnosis of hepatocellular carcinoma (HCC) based on genes whose specificity and level of expression are the most discriminating for the diagnosis of HCC. The level of expression of 219 genes was assessed with a real-time reverse transcription-polymerase chain reaction approach in a training set of samples including normal livers (15), cirrhosis (12), and HCC (16). The most informative genes were selected for the molecular index. This index was prospectively validated in a new set of 40 samples (testing set) and in a set of 45 cirrhotic macronodules. 44 out of the 219 genes were differentially expressed in HCC. 13 out of these 44 genes were finally selected for the molecular index according to their diagnostic performance and after exclusion of most redundant genes. Using this index, 42 out of 43 samples of the training set and 39 out of the 40 samples of the testing set were correctly ranked as HCC or not HCC (normal liver or cirrhosis). The index also enabled correct ranking of 44 out of 45 cirrhotic macronodules into 2 groups: benign (including macroregenerative and dysplastic macronodules) and malignant macronodules. This molecular diagnostic index is an efficient tool both for identification of overt HCC as well as minute lesions (cirrhotic macronodules). It might be useful to correctly diagnose borderline lesion or small well-differentiated hepatocellular carcinomas whose diagnosis is often difficult on a histopathological basis.

Adolescent↗

The identification of small nodules in liver adenomatosis.

BACKGROUND/AIMS: Liver adenomatosis is characterized by the presence of multiple adenomas of various sizes in the liver. The aim of this study was to characterize the morphology of small nodules which can be difficult to identify. METHODS: Seven patients included in this study underwent surgery for the removal of one or several nodules. All, but one, were females. Three out of seven presented with acute bleeding. Five had six or more nodules at presentation, and two only one, who developed nodules later on during follow-up. RESULTS: All of the large nodules that were >2 cm, except one, were typical adenomas with or without hemorrhagic areas. Smaller nodules (1-2 cm), some of which discovered on the resected specimen were either typical adenomas or non-typical nodules. These non-typical nodules were characterized by a polylobulated aspect with steatotic zones, and in between, bands of non-steatotic hepatocytes with portal tracts-like structures containing occasional cytokeratin 7 and less often cytokeratin 19 positive biliary cells. Numerous steatotic foci were also seen in four cases. They were isolated or grouped forming microadenomas or non-typical micronodules (<1 cm) containing biliary elements. Our findings lead to the following hypothesis: adenomatosis is characterized by the simultaneous occurrence of multiple adenomas; if several adenomatous foci expand at the same time in the same area, they will form one polylobulated nodule containing non-adenomatous tissue with portal tracts in between areas of adenomatous tissue (non-typical micronodule). Such a small micronodule may in turn expand and join another micronodule to form a bigger one by the same process (non-typical nodule). As nodules grow, their non-adenomatous components including hepatocytic plates and portal tracts constituents will progressively disappear to end up with the classical aspect of an adenoma. CONCLUSIONS: This hypothesis supports the concept that non-typical nodules/micronodules are adenomas precursors. However, they can be difficult to classify since they resemble focal nodular hyperplasia precursor.

Adenoma↗