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Biomedical subjects

R Bouvier

Publications and source records attributed to R Bouvier.

At least 37 records · Page 2Linked to original sources

[Meconium periorchitis. Two case reports].

CASE REPORTS: Two cases of meconium periorchitis respectively in a ten-day- and a five-month-old infant are reported. The presenting symptom was a scrotal mass, isolated in one case and associated with pain and inflammation in the other case. Intraoperative histological diagnosis allowed conservative surgery in one case. COMMENTS: About 40 cases of scrotal manifestations of an intrauterine perforation of the gastrointestinal tract are reported in the literature. In cases with associated intraperitoneal calcifications, the diagnosis is easy and surgical exploration may be avoided, spontaneous resolution being the rule. However, in half of the cases, a scrotal mass is the only manifestation and raises the question of a testicular tumor. CONCLUSION: Unfamiliarity with this unusual entity may lead to unnecessary orchiectomy.

Diagnosis, Differential↗

Does nephroblastomatosis influence the natural history and relapse rate in Wilms' tumour? A single centre experience over 11 years.

The presence of multifocal or diffuse nephrogenic rests (NRs) in one or both kidneys is termed nephroblastomatosis (Nbm). Nbm may be a predisposing factor for Wilms' tumour (WT). The aim of this retrospective study was to evaluate the impact of Nbm on the outcome of WT in children. We assessed the outcome of 81 children with Wilms tumours and practical implications of Nbm in the treatment and follow-up. All the pathology slides have been reviewed in 1997. 63 had WT without Nbm (group A) and 18 had WT associated with Nbm (group B). There was no statistical difference between the two groups according to the age at diagnosis and histology. Clinical abnormalities were more frequent in group B (33 versus 8%). There was no statistical difference between the percentage of stage IV in both groups, but bilaterality (stage V) was present only in the group B. Relapse was observed in 20/81 patients (25%): 11 (17%) in group A and 9 (50%) in group B. Mean delay of relapse was longer (25 months) in group B than in group A (10 months). For the whole population, with a median follow-up of 9 years, the event-free survival (EFS) and the overall survival (OS) probabilities were respectively 74%+/-10 and 83%+/-9 at 120 months. The difference in EFS between groups A (82+/-9%) and B (38%+/-29) was significant (P=0.004). The discovery of Nbm in the non-tumoral part of the kidney with WT can be an adverse factor and in particular favours the subsequent development of a new Wilms tumour. It justifies separate follow-up guidelines.

Adolescent↗

[Standards, Options, and Recommendations for brachytherapy in patients with prostate cancer: efficacy and toxicity].

CONTEXT: The "Standards, Options and Recommendations" (SOR) collaborative project was initiated in 1993 by the Federation of the French Cancer Centres (FNCLCC), with the 20 French Regional Cancer Centres, several French public university and general hospitals, as well as private clinics and medical specialty societies. Its main objective is the development of serviceable clinical practice guidelines in order to improve the quality of health care and the outcome of cancer patients. The methodology is based on a literature review, followed by a critical appraisal by a multidisciplinary group of experts. Draft guidelines are produced, then validated by specialists in cancer care delivery. OBJECTIVES: Produce clinical practice guidelines for the brachytherapy of prostate cancer using the methodology developed by the Standards, Options and Recommendations project. METHODS: The FNCLCC and the French Urology Association (AFU) first designated the multidisciplinary group of experts. Available data were collected by a search of Medline and lists selected by experts in the group. A first draft of the guidelines was written, they validated by independent reviewers. RESULTS: The main recommendations are: 1/Brachytherapy with permanent seeds alone is a possible curative treatment for prostate cancer patients with the following prognosis factors: tumour stage T1 or T2a (TNM 1992), Gleason score < or = 6 and PSA < 10 micrograms/L. 2/Combined treatment with brachytherapy and hormonal therapy could be more efficient than brachytherapy alone for prostate cancer patients with Gleason score > 7 and/or PSA > 10.3/Combination of brachytherapy and external beam radiation therapy can be proposed to prostate cancer patients with intermediate prognosis. 4/Before and after seed implantation, risks of infection must be prevented by appropriate antibiotic therapy (recommendation). 5/Brachytherapy must not be performed within 2 months of transurethral prostate resection. 6/The height of the urethra receiving more than 200% of the prescribed dose must be reported. The portion of the rectum receiving 100 and 120% of the prescribed dose must be limited to 10 and 5 mm length, respectively.

Antineoplastic Agents, Hormonal↗

Expression of hMLH1 and hMSH2 and assessment of microsatellite instability in testicular and mediastinal germ cell tumours.

The aim of this study was to investigate DNA mismatch repair deficiency in male germ cell tumours. We analysed the expression of two mismatch repair proteins, human mutL homologue 1 (hMLH1) and human mutS homologue 2 (hMSH2), and evaluated the frequency of microsatellite instability with 10 mononucleotide and two dinucleotide repeat sequences, in 39 paired tumour/normal DNA samples obtained from 17 testicular and two mediastinal germ cell tumours. In all 19 cases, hMLH1 and hMSH2 both showed nuclear immunolocalization in invasive and testicular in-situ tumours. In non-neoplastic seminiferous tubules, hMLH1 was expressed only in premeiotic germ cells, while hMSH2 was seen in all stages of spermatogenesis. Genetic analysis of dinucleotide markers revealed loss of heterozygosity in one of two testicular yolk sac tumours at D18S58 and an allelic shift at D2S123 in two of three testicular embryonal carcinomas, while none of the 12 seminomas exhibited a genetic abnormality at these loci. No abnormalities were demonstrated with the 10 mononucleotide markers. The two mediastinal germ cell tumours showed no genetic instability or allelic loss with all 12 markers. We suggest that genetic alterations as assessed by microsatellite analysis in germ cell tumours may reflect tissue maturation and phenotypic differentiation rather than tumour progression. In addition, we suggest that hMLH1 and hMSH2 genes may not be implicated in the genesis of germ cell tumours.

Adaptor Proteins, Signal Transducing↗

Collagenous gastritis: a report of six cases.

Collagenous gastritis is an exceptional entity with eight cases documented to date characterized by the presence of a thick subepithelial collagen band associated with an inflammatory infiltrate of the gastric mucosa. The aim of our study was to describe the clinical and histologic characteristics of six new cases of collagenous gastritis. All cases showed a subepithelial collagen band that averaged 30 microm but often measured up to 120 microm. This finding was almost always accompanied by mixed chronic inflammation in the lamina propria and by surface epithelial damage of varying severity. Our study seems to delineate two subsets in patients with collagenous gastritis: 1) collagenous gastritis occurring in children and young adults presenting with severe anemia, a nodular pattern on endoscopy, and a disease limited to the gastric mucosa without evidence of colonic involvement, and 2) collagenous gastritis associated with collagenous colitis occurring in adult patients presenting with chronic watery diarrhea. These findings highlight the fact that subepithelial collagen deposition may be a generalized disease affecting the entire gastrointestinal tract.

Adult↗

Association of GSTT1 non-null and NAT1 slow/rapid genotypes with von Hippel-Lindau tumour suppressor gene transversions in sporadic renal cell carcinoma.

The von Hippel-Lindau (VHL) tumour suppressor gene is commonly mutated in renal cell carcinoma of clear cell type (CCRCC). We investigated the possible relationship between VHL mutations in sporadic CCRCC and polymorphism of genes encoding enzymes involved in carcinogen metabolism: two cytochrome P450 monooxygenases (CYP1A1 and CYP2D6), one NAD[P]H:quinone oxidoreductase (NQO1), three glutathione S-transferases (GSTM1, GSTT1 and GSTP1) and two arylamine N-acetyltransferases (NAT1 and NAT2). We analysed DNA from tumour and nontumoural kidney tissue from 195 CCRCC patients. Single VHL mutations were identified in 88 patients and double mutations were present in two patients. Nine of 18 transversions were GC to TA, four were AT to TA, four were GC to CG and one was AT to CG. Ten of 19 transitions were GC to AT and nine were AT to GC. We also identified 53 frameshifts and two GC to AT at CpG. An excess of transversions was observed in a subset of patients with active GSTT1 [GSTT1 (+) genotype] and probably defective NAT1 (NAT1 S/R variant genotype). All 18 transversions were in GSTT1 (+) patients, whereas only 76% of transitions (P = 0.05) and 81% of the other mutations (P = 0.06) occurred in this genotype. We found that 28% of the transversions were in the NAT1 S/R genotype versus 12% of the transitions (P = 0.40) and 4% of the other mutations (P = 0.01). This suggests that pharmacogenetic polymorphisms may be associated with the type of acquired VHL mutation, which may modulate CCRCC development.

Acetyltransferases↗

Transrectal high intensity focused ultrasound for the treatment of localized prostate cancer: factors influencing the outcome.

OBJECTIVES: Efficacy evaluation of high intensity focused ultrasound (HIFU) treatment for localized prostate cancer and identification of the factors affecting the outcome. PATIENTS AND METHODS: 102 patients with prostate cancer stage T1-T2 and noncandidates for radical prostatectomy have been treated with HIFU (Ablatherm, EDAP-Technomed). The disease progression (failure) was strictly defined by any positive sample at control biopsies, whatever the prostate-specific antigen (PSA) level, or by 3 consecutive increases in PSA levels in case of negative biopsies. RESULTS: At inclusion, patients' baseline characteristics were (mean +/- standard deviation): age 70.8 (+/-6.13) years, PSA 8.38 (+/-4.8) ng/ml, prostate volume 33.3 (+/-16.71) cm3. The population mean follow-up was 19 months (3-76 months). The overall success rate was 66%. Statistically significant variations of the overall success with a more favorable outcome were observed when (1) the initial PSA level was < or =10 ng/ml (73 vs. 50%, p = 0.02), (2) the Gleason score was < or =6 (81 vs. 46%, p<0.001) and (3) the pretreatment sextant biopsy evidenced 1-4 positive samples (68 vs. 40%, p = 0.01). CONCLUSION: Results observed after HIFU treatment in localized prostate cancer are now challenging those obtained after radiation therapy. The success rate is influenced by disease-related prognostic factors.

Aged↗

MRI appearance of prostate following transrectal HIFU ablation of localized cancer.

OBJECTIVES: To evaluate the accuracy of gadolinium-enhanced MRI in gauging the extent of the tissue damage induced by transrectal high intensity focused ultrasound (HIFU) therapy and to assess how well the results obtained with this modality correlate with histological findings (control biopsies). METHODS: Twenty-one patients with biopsy-proven prostate cancer (T1-T2-T3a, Nx, M0) who gave informed consent were included in the protocol. They underwent pre- and postoperative (2-5 days after HIFU treatment) MR examinations. Fifteen patients also underwent a follow-up MR examination 1-5 months postoperatively. MR findings were compared with the results of postoperative transrectal biopsy examinations. RESULTS: The prostate volume increased after the HIFU session from 43.9+/-18.6 to 52.1+/-21 cm(3) by day 2 (p<0.001). On fat-saturated gadolinium-enhanced T1-weighted images, the treated area appeared as a hypointense zone surrounded by a peripheral rim of enhancement in all patients. A positive correlation (r = 0.75) was found between the volume of the hypointense zone measured at days 2-5 (30+/-11 cm(3), 67% of the posttreatment prostate volume) and the theoretical target volume (22+/-5 cm(3), 61% of the initial prostate volume). MRI showed that the anterior part of the base was not reached by the ultrasound beam. The mean volume of the untreated zone (prostate without any MRI modifications) was 8 cm(3) (range, 0.4-36). No correlation was found between the MRI appearance of the treated area and the intensity of the necrosis or the presence of foci of residual, viable cancer. CONCLUSION: Gadolinium-enhanced MRI is an accurate way of determining the extent of tissue damage induced in HIFU ablative therapy, but cannot predict histological results.

Aged↗

[Conjunctival epithelial carcinoma in a 9-year-old child with xeroderma pigmentosum. Case report].

We report the case of a conjunctival tumor in a 9-year-old patient, suffering from Xeroderma Pigmentosum. Our patient presented a raspberry-colored conjunctival tumor. The tumor was resecked without any additional treatment. The histological study revealed squamous cell carcinoma. A suspicion of relapse appeared two months later of the same location and a new resection was performed. The initial checkup of this tumor was negative. In this disease, ocular localizations are frequent. The conjunctiva, the cornea, the eyelids and, into a lesser extent, the orbit can be involved. Basal cell carcinoma and squamous cell carcinoma are the most frequent tumors observed in Xeroderma Pigmentosum. Their treatment is mainly surgical.

Carcinoma, Squamous Cell↗

Somatostatin receptor expression profile as a potential criterion for discrimination between seminoma and non-seminoma testicular tumors.

The expression of five (sst1-sst5) somatostatin (SRIF) receptor mRNAs was compared between normal and tumoral testicular samples diagnosed as either seminoma or non-seminoma. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis indicated that all testicular tissues studied (total of 24) contained sst5 receptor transcripts, whereas the sst2 was absent in all of them. In contrast to the normal tissue samples, both types of tumors (total of 12) did not contain sst4 transcripts. sst3 mRNA was expressed in normal and non-seminoma samples, but not in seminomas. sst1 transcripts were not found in normal and seminoma tissues. However, all studied non-seminomas contained this mRNA. Our data thus points to a specific pattern of SRIF receptor mRNA expression in each type of the samples analyzed. Moreover, they further indicate that the presence of sst1 and sst3 transcripts might be used as an additional criterion to distinguish between seminoma and nonseminoma tumors.

Adolescent↗

Cytomegalovirus infection may cause ureteral necrosis.

Cytomegalovirus (CMV) infection has protean presentation among immunocompromised patients, but the urinary tract is rarely involved. We report a case of extensive ureteral necrosis in a renal transplant, 12-year-old patient with typical histological feature of CMV inclusions. The role of CMV was confirmed by immunohistochemical analysis and concomitant CMV DNA detection in peripheral blood leukocytes by polymerase chain reaction analysis. CMV infection can, therefore, be regarded as a possible cause of ureteral necrosis in renal transplant recipients.

Child↗

A novel SMAD4 gene mutation in seminoma germ cell tumors.

Transforming growth factor (TGF)-beta is known as an antiproliferative factor in the majority of mammalian cells, including stem germ cells. Lack of TGF-beta-induced growth inhibition has been associated with disruptions of TGF-beta receptors and SMADs. In the present study, we performed a mutational analysis of the TGF-beta signaling system, including TGF-beta receptor type I and type II and SMADs (SMAD1-SMAD7), in 20 seminoma germ cell tumors. Using reverse transcription-PCR, single-strand conformational polymorphism, and sequencing analysis, the COOH-terminal domain of SMAD4 was found to be mutated: a single thymine was inserted between nt 1521 and 1522 in 2 of 20 tumors analyzed. This addition of a thymine creates a frameshift and a new stop signal at codon 492, which leads to premature termination of the encoded protein. Such a mutation potentially abrogates signaling from TGF-beta as well as the other TGF-beta family members, including activin and bone morphogenetic protein, which all use the SMAD pathway. Immunohistological analysis confirmed the loss of expression of SMAD4 protein in the seminoma tissues with the insertional mutation. To our knowledge, this is the first description of a novel SMAD4 insertional mutation in seminoma testicular germ cell tumors. This mutational inactivation of SMAD4/COOH-terminal domain may cause TGF-beta unresponsiveness. It could thus provide a basis for understanding the potential role of the TGF-beta system in germ cell tumorigenesis.

Amino Acid Sequence↗

Membranous nephropathy and orbital malignant tumor.

A 7-year-old girl with membranous nephropathy is reported who suffered 16 months later from an orbital rhabdomyosarcoma. Proteinuria disappeared at the time of the remission of the tumor. Membranous nephropathy as paraneoplastic syndrome is exceptional in children, since only two other cases associated with a solid tumor have been reported in the literature.

Child↗

[Liver transplantation in infants and children. Evaluation of the first 40 cases (March 1991-March 1997)].

BACKGROUND: Liver transplantation (LT) is the treatment of end-stage liver disease in children. We report our experience with LT using grafts from living related (LRD) and cadaver donors (CD). POPULATION: From March 1991 to March 1997, 40 children and infants received a total of 42 liver grafts. A reduced-size liver was used in 28 cases. We studied pre-transplantation status, survival rate, and medical and surgical complications in these patients. RESULTS: The survival rate in our series was respectively 85 and 80% at 1 and 7 years after LT. Low weight infants required a prolonged ventilatory assistance. Five of the six deaths noticed during the first three months after LT occurred in children weighing less than 12 kg. One year after LT, no significant difference in the incidence of rejection was found, neither between low-weight children and the others, nor between patients transplanted from CD or LRD. Biliary tract stricture was the major surgical complication. CONCLUSION: This series consisted of a majority of low-weight children. The survival rate in the patients weighting less than 12 kg is lower than in the others. This may be explained by the nutritional status of these patients and early postsurgical complications. The use of grafts from living donors offers more flexibility since the operation is performed electively, but it did not seem to modify the incidence of acute rejections and surgical complications.

Adolescent↗

Transrectal high-intensity focused ultrasound: minimally invasive therapy of localized prostate cancer.

BACKGROUND AND PURPOSE: Criteria for determining the durability of the response to transrectal high-intensity focused ultrasound (HIFU) ablation of prostate cancer have been established by calculating progression-free probability. PATIENTS AND METHODS: A series of 82 patients (mean age 71 +/- 5.7 years) with biopsy-proven localized (stage T1-T2) cancer who were not suitable candidates for radical surgery underwent transfectal HIFU ablation with the Ablatherm machine. The mean follow-up was 17.6 months (range 3-68 months). The mean serum prostate specific antigen (PSA) value and mean prostate volume were 8.11 +/- 4.64 ng/mL and 34.9 +/- 17.4 cm3, respectively. Progression was rigidly defined as any positive biopsy result, regardless of PSA concentration, or three successive PSA increases for patients with a negative biopsy (PSA velocity > or = 0.75). Times to specific events (positive biopsy and PSA elevation) were analyzed with the Kaplan-Meier survival method. RESULTS: Overall, 62% of the patients exhibited no evidence of disease progression 60 months after transrectal HIFU ablation. In particular, the disease-free rate was 68% for the moderate-risk group of 50 patients (PSA < 15.0 ng/mL, Gleason sum < 8, prostate volume < 40 cm3, and number of positive biopsies < 5). For the low-risk group of 32 patients (PSA < 10 ng/mL and Gleason sum < 7), the disease-free survival rate was 83%. CONCLUSION: Transrectal HIFU prostate ablation is an effective therapeutic alternative for patients with localized prostatic adenocarcinoma.

Adenocarcinoma↗