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L Boccon-Gibod

Publications and source records attributed to L Boccon-Gibod.

At least 37 records · Page 2Linked to original sources
PubMed2001

Frequency of renal phosphate leak among patients with calcium nephrolithiasis.

BACKGROUND: Nephrolithiasis is a frequent disorder affecting 10 to 15% of the population in Europe and the United States. More than 80% of renal stones are made of calcium oxalate and calcium phosphate. The main identified risks for calcium renal stone formation are hypercalciuria and urinary saturation. A urine phosphate (Pi) loss is often associated with hypercalciuria; furthermore, hyperphosphaturia increases urinary saturation. METHODS: To determine whether urinary phosphate loss is associated with calcium urolithiasis, we measured renal Pi threshold (TmPi) in 207 stone formers with normal parathyroid hormone (PTH) serum concentration and in 105 control subjects. RESULTS: The TmPi followed a normal distribution in both groups. The mean TmPi was significantly lower in stone formers versus controls (0.72 +/- 0.13 vs. 0.87 +/- 0.18 mmol/L, P < 0.0001) because of a shift to the left of the TmPi distribution curve in the stone former population, with no evidence for bimodal distribution. Five percent of the controls had a TmPi <0.63 versus 19% of the stone formers. Daily urinary calcium excretion was significantly higher in stone formers than in controls. Calcium excretion was also significantly higher in stone formers with TmPi <0.63 mmol/L compared with those with TmPi > or =0.63. Serum PTH and ionized calcium concentrations were not different in stone formers and in control subjects, whatever the TmPi value. CONCLUSIONS: : A low TmPi is more frequently encountered in stone formers with a normal PTH concentration than in control subjects and is associated with a high urinary Ca excretion. The hypophosphatemia induced by a renal phosphate leak may predispose the subject to calcium stone formation by increasing the serum calcitriol level, calcium excretion, and urinary saturation.

Adult↗
PubMed2001

Osteochondromyxoma of bone: a congenital tumor associated with lentigines and other unusual disorders.

This article describes the clinical and pathologic features of four unusual bone tumors. Three were congenital or most likely so; the fourth, detected at age 1 year, was probably of considerable duration. The patients, three boys and one girl, each presented with a painless mass. Two had the Carney complex, a familial lentiginous and multiorgan tumorous syndrome; another probably had this disorder; the fourth did not show it, but his mother did. The tumors occurred in the nasal region (n = 2) and the diaphysis of the tibia and radius (n = 1 each). Roentgenographically, three had benign characteristics; the fourth, malignant features. Grossly, the tumors were gelatinous, cartilaginous. and bony. Microscopically, they featured benign-appearing polymorphic cells with few division figures arranged in sheets and lobules set in a myxomatous, cartilaginous, osseous, and hyaline fibrous matrix. Cellularity was low to moderate. The tumors eroded bone, one infiltrated between bony trabeculae, and three had soft tissue extension. Complete resection of one tumor was curative; incomplete excision of two tumors resulted in local recurrence (intracranial and fatal) in one and persistence in the other; the fourth tumor remains under observation after biopsy. No tumor metastasized.

Bone Neoplasms↗
PubMed2001

Rising PSA with a negative biopsy.

The use of prostate-specific antigen (PSA) as a diagnostic and screening tool has led to a significant rise in the numbers of patients undergoing prostate biopsy. However, the specificity of the PSA test is low, and the majority of patients in the diagnostically uncertain serum PSA range of 4-10 ng/ml will be negative for prostate cancer on biopsy. In addition, current biopsy techniques are sub-optimal. Improvements in technique are needed to increase the tumour detection rate and reduce the number of repeat biopsies. Several biopsy techniques have now been described that sample the prostate gland more effectively, by taking extra core samples in addition to the established sextant biopsy core samples. Sampling of peripheral areas of the gland results in significantly improved tumour detection rates while morbidity to the patient is not increased. The presence of prostatic intraepithelial neoplasia (PIN) is evidence that cancer is present, or is likely to appear, in the prostate, but has not been sampled in the biopsy. In the event of a rising PSA and negative biopsy, serum free/total PSA (% free PSA) measurement can be beneficial in discriminating between cancer and other possible causes of raised PSA, such as benign prostatic hyperplasia. PIN in association with reduced % free PSA is a valuable indicator in the decision to carry out a repeat biopsy.

Biopsy↗
PubMed2001

Pulmonary sarcoidosis in children: a follow-up study.

Progression of pulmonary sarcoidosis in children remains poorly documented. The aim of this work was to gather follow-up information on pulmonary outcomes in children with sarcoidosis and to obtain data of relevance to a discussion of the optimal length and regimen of glucocorticoid therapy. In the present study, the authors experience of pulmonary sarcoidosis in 21 children referred to the paediatric pulmonary department over a 10-yr period is reported with a documented follow-up of at least 4 yr. Evaluation of the disease during the follow-up included analysis of clinical manifestations, chest radiographs, pulmonary function tests with measurements of the vital capacity (VC), dynamic lung compliance (CL,dyn), lung transfer for CO (TL,CO), and arterial blood gases, as well as bronchoalveolar lavage (BAL) with determination of total and differential cell counts. After initial evaluation the decision was a careful observation of four children without therapy. Corticosteroid treatment was initiated in 17 children. Analysis of results indicated that after 6-12 months of treatment most clinical manifestations of the disease and chest radiograph abnormalities disappeared, and beneficial effects on VC and TL,CO were apparent. After 18 months of steroids no benefit on pulmonary function tests could be noticed, with mainly persistence of alterations of CL,dyn. Results of BAL studies documented the presence of an alveolitis with increased lymphocyte populations throughout the follow-up. Relapses were observed in four children during tapering of prednisone; they were not reported after discontinuation of steroid therapy. Taken together data obtained in the presented population can lead to the following suggestions for the management of pulmonary sarcoidosis in children. BAL should be performed at the initial evaluation to document alveolitis; however, nothing seems to be gained from repeating this investigation during follow-up in the absence of specific reasons. Once the decision to initiate glucocorticoid therapy is made, 18 months may be a reasonable treatment duration. Discontinuation of therapy can be decided even if the pulmonary function tests remain abnormal, but the child should then be carefully monitored for a relapse.

Adolescent↗
PubMed2001

Prospective evaluation of prostate cancer detected on biopsies 1, 2, 3 and 4: when should we stop?

PURPOSE: We evaluated biochemical parameters and pathological features, as well as biopsy related morbidity of prostate cancer detected on biopsies 2, 3 and 4 in men with total serum prostate specific antigen (PSA) between 4 and 10 ng./ml. These features were compared to those detected on prostate biopsy 1. MATERIALS AND METHODS: In this prospective European Prostate Cancer Detection study 1,051 men with total PSA between 4 and 10 ng./ml. underwent transrectal ultrasound guided sextant biopsy and 2 additional transition zone biopsies. All patients in whom biopsy samples were negative for prostate cancer underwent biopsy 2 after 6 weeks. If also negative, biopsies 3 and even 4 were performed at 8-week intervals. Those patients with clinically localized cancer underwent radical prostatectomy. Pathological and clinical features of patients diagnosed with cancer on either biopsy 1 or 2 and clinically organ confined disease who agreed to undergo radical prostatectomy were compared. RESULTS: Cancer detection rates on biopsies 1, 2, 3 and 4 were 22% (231 of 1,051), 10% (83 of 820), 5% (36 of 737) and 4% (4 of 94), respectively. Overall, of the patients with clinically localized disease, which was 67% of cancers detected, 86% underwent radical prostatectomy and 14% opted for watchful waiting or radiation therapy. Overall, 58.0%, 60.9%, 86.3% and 100% of patients had organ confined disease on biopsies 1, 2, 3 and 4, respectively. Despite statistically significant differences in regard to multifocality (p = 0.009) and cancer location (p = 0.001), including cancer on biopsy 2 showing a lower rate of multifocality and a more apico-dorsal location, there were no differences in regard to stage (p = 0.2), Gleason score (p = 0.3), percent Gleason grade 4/5 (p = 0.2), serum PSA and patient age between biopsies 1 and 2. However, cancer detected on biopsies 3 and 4 had a significantly lower Gleason score (p = 0.001 and 0.001), lower rate of grade 4/5 (p = 0.02), and lower volume (p = 0.001 and 0.001) and stage (p = 0.001), respectively. CONCLUSIONS: Despite differences in location and multifocality, pathological and biochemical features of cancer detected on biopsies 1 and 2 were similar, suggesting comparable biological behaviors. Cancer detected on biopsies 3 and 4 had a lower grade, stage and volume compared with that on biopsies 1 and 2. Morbidity on biopsies 1 and 2 was similar, whereas biopsies 3 and 4 had a slightly higher complication rate. Therefore, biopsy 2 in all cases of a negative finding on biopsy 1 appears justified. However, biopsies 3 and 4 should only be obtained in select patients with a high suspicion of cancer and/or poor prognostic factors on biopsy 1 or 2.

Aged↗
PubMed2001

[Can a precise vesiculectomy be performed during radical prostatectomy?].

OBJECTIVE: To define the anatomical landmarks allowing precise vesiculectomy to be performed during radical prostatectomy for cancer. MATERIAL AND METHODS: 12 non-formalin-preserved anatomical subjects were dissected as during retropubic and perineal prostatectomy, with and without coloured latex vascular injection. RESULTS: Three anatomical landmarks were defined: 1) Denonvilliers' fascia; 2) vas deferens; 3) arteries supplying the seminal vesicles. CONCLUSIONS: These three anatomical landmarks ensure: complete resection, preservation of adjacent anatomical structures and elective haemostasis.

Aged↗
PubMed2000

Complete necrosis induced by preoperative chemotherapy in Wilms tumor as an indicator of low risk: report of the international society of paediatric oncology (SIOP) nephroblastoma trial and study 9.

BACKGROUND: The SIOP Nephroblastoma therapeutic protocols include a period of preoperative chemotherapy followed by nephrectomy and a period of postoperative chemotherapy. From the outset, identification of low-risk groups has been an aim of the SIOP Nephroblastoma Trials and Studies. Now that 90% of children with Wilms tumor can be cured, attention is even more focused on the identification of patients who could benefit from less aggressive postoperative therapy, thus minimizing the morbidity and late effects associated with treatment. The prognostic implications of total necrosis in nephroblastoma after chemotherapy have not been investigated hitherto. PROCEDURE: Between November 1, 1987 and June 30, 1993, 599 patients referred to the SIOP-9 Nephroblastoma Trial and Study were preoperatively treated and classified as stages I-IV nonanaplastic Wilms tumor. RESULTS: Of these 599 patients, pathologic examination of the nephrectomy specimen revealed a completely necrotic Wilms tumor (CNWT) with no viable tumor remaining in 59 (10%): these comprised 37 stages I-III and 22 stage IV. Of these patients, 58 (98%) had no evidence of disease at 5 years vs. 90% for the rest of the cohort (P < 0.05). Stages I-III patients represented 63% of CNWT and had a 97% overall survival rate. The only death was related to veno-occlusive disease and occurred in a stage I patient in the month following nephrectomy. Stage IV patients represented 37% of CNWT (vs. only 10% of all other cases of unilateral nonanaplastic Wilms tumor) and had a 100% rate of survival. Children with CNWT were older (mean 59 months vs. 43 months); their tumor at diagnosis was larger and had regressed more significantly at subsequent ultrasound examination. The data also uphold the hypothesis that Wilms tumors of blastemic pattern are most aggressive, but also are extremely responsive to chemotherapy. CONCLUSIONS: Patients with unilateral nonanaplastic WT that showed total necrosis following preoperative chemotherapy had excellent outcome and should benefit from less aggressive postoperative treatment in further trials. Other very responsive tumors, such as Wilms with <10% viable tumor, should also be assessed.

Adolescent↗
PubMed2000

Absence of microsatellite instability in transitional cell carcinoma of the bladder.

OBJECTIVES: To investigate the prevalence of the microsatellite instability related to mismatch repair (MMR) gene defects using a panel of six microsatellite markers, as recommended by a recent workshop on microsatellite instability in colon cancer, because it is still unclear whether abnormalities in DNA MMR genes are involved in transitional cell carcinoma (TCC) of the bladder. METHODS: Three mononucleotide repeats (BAT26, TGFbetaRII, and BAX) were studied in 33 TCC samples and in four bladder cancer cell lines. Three dinucleotide repeats (D2S123, D5S346, and D17S250) were studied in 21 of these 33 TCC samples. RESULTS: No alteration was detected either in the 33 TCC samples analyzed or in the four bladder cancer cell lines (T24, J82, 647V, and 1207) studied. A difference between normal and tumor DNA was observed in only 1 of 21 tumor samples for D17S250. CONCLUSIONS: These data indicate that microsatellite instability is very uncommon in TCC of the bladder.

Aged↗
PubMed2000

Percentage of cancer on biopsy cores accurately predicts extracapsular extension and biochemical relapse after radical prostatectomy for T1-T2 prostate cancer.

PURPOSE: To perform a multivariate analysis to investigate the usefulness of eight preoperative variables as predictors of final pathological stage (pT), positive surgical margins (PSM) and biological progression after radical prostatectomy (RP). MATERIALS AND METHODS: In 143 patients undergoing RP for T1-T2 prostate cancer, the respective values of age, clinical stage, preoperative prostate-specific antigen (PSA), prostate-specific antigen density (PSAD), number of positive biopsies (NPB), Gleason score, length of tissue core invaded by cancer (LTI) and topography (uni/bilaterality) of positive biopsies for predicting extracapsular extension, PSM and biochemical failure (PSA> or =0.05 ng/ml) were evaluated retrospectively. Univariate and multivariate analyses were applied to define the statistical significance of each variable. Actuarial survival without biological progression was calculated using the Kaplan-Meier method (log-rank test). RESULTS: In this series, 44.8% of patients had extracapsular extension with 41.3% PSM. The mean PSA was 12.4 ng/ml. In univariate analysis, LTI (p<0.0001), NPB (p = 0.0023), PSA (p = 0.0039) and Gleason score (p = 0.0136) were the most powerful variables to predict pT stage; however, in logistic regression analysis, LTI was the most predictive feature. For prediction of PSM, some variables (LTI, NPB and PSA) were found to be of statistical value in univariate analysis, and LTI in combination with NPB and PSA in multivariate analysis. For biological progression, statistical analysis (log rank test) showed PSAD and LTI to be significant predictors. CONCLUSION: The pathological report regarding the biopsy contains crucial information influencing the prediction of pT stage, PSM and biological progression after RP. LTI, NPB and PSA are the most useful parameters for this purpose.

Adult↗
PubMed2000

Role of preoperative positive apical biopsies in the prediction of specimen-confined prostate cancer after radical retropubic prostatectomy: a multi-institutional study.

OBJECTIVES: A multi-institutional study of 280 radical prostatectomy specimens obtained from three independent academic hospitals was undertaken to validate a nomogram developed for the prediction of specimenconfined protstate cancer after prostatectomy. METHODS: Three preoperative factors - the Gleason score, prostatespecific antigen (PSA) and apical location of positive biopsies - that were identified with a previous logistic regression formula were collected. Links between margin status and preoperative criteria were confirmed by univariate methods. Subsequently, the predictive indexes of positive margins were calculated and compared to the actual margin status in terms of predictive characteristics. RESULTS: This control series, independent of the initial series that was used to identify the relevant preoperative factors, confirmed that positive apical biopsies(p<0.001), PSA (p<0.005) and the Gleason score (p<0.005) were strongly linked to the occurrence of positive margins. Different cutoff values for the predictive index were compared in a receiver operating characteristic curve. A value of 0.5, similar to the one described in the original series, gave an adequate compromise between sensitivity and specificity with respective values of 68 and 73% and a test accuracy of 72%. In practical terms, it was possible to predict 85% of negative margins, and to delineate two groups with different rates of positive margins (14.5 vs. 50%). CONCLUSIONS: We demonstrated that PSA, the Gleason score and apical biopsy status are cumulative risk factors for positive margins. Risk of positive margins increases when it is not possible to obtain a wide excision of periprostatic fascia, as at the apex. This study substantiates the independent prognostic value of positive preoperative apical biopsies for predicting positive surgical margins.

Aged↗
PubMed2000

Establishment and characterization of a human adrenocortical carcinoma xenograft model.

Adrenocortical carcinomas are rare malignant tumors. They have a poor prognosis, as they are often diagnosed late and are usually resistant to chemotherapy. The lack of a suitable animal model for these tumors has been a major obstacle to the evaluation of new therapeutic agents. The aim of this study was to establish and characterize xenografts of the human adrenocortical carcinoma NCI H295R cell line as a model of adrenocortical carcinoma for future therapeutic trials. This cell line was sc injected (6 x 10(6) cells) into nude mice (n = 20). Solid tumors were locally measurable after 45 days at 90% of the inoculation sites. The xenografts were similar histologically to the original adrenocortical carcinoma from which the cell line was derived. The xenografts precisely reproduced the dysregulation of the insulin-like growth factor (IGF) system [overexpression of the IGF-II and IGF-binding protein-2 (IGFBP-2) genes] typical of adrenocortical carcinoma. Similarly to adrenocortical carcinomas, human IGFBP-2 (but not IGF-II) was secreted in mouse plasma. We analyzed steroid production (cortisol, 17-hydroxypregnenolone, 17-hydroxyprogesterone, dehydroepiandrosterone, delta4-androstenedione, 11-deoxycortisol, corticosterone, and testosterone). Xenografts produced all three class of steroids, with the preferential production of androgens of the delta4 pathway. The H295R xenograft model is a good model of human adrenocortical carcinoma, as it mimics dysregulation of the IGF system usually found in these tumors. It also produces IGFBP-2 and steroids that can be used as tumor markers. This model may therefore be useful for evaluating therapeutic agents.

Adrenal Cortex Neoplasms↗
PubMed2000

[Innervation of Denonvilliers' recto-vesical fascia. Anatomical study].

OBJECTIVE: Dissection of Denonvilliers' rectovesical fascia allows easy cleavage of the prostatorectal and prostatovesical spaces. Its lateral limit in the "neurovascular pedicles" justifies its resection during radical prostatectomy. The objective of this study was to define the course and to observe the structure of nerves crossing the rectovesical fascia, as the sheaths of these nerves may be invaded by prostatic adenocarcinoma tumour cells. MATERIAL AND METHODS: After dissection of a fresh cadavre to define the relations of this fascia with the pedicles, rectovesical fascia biopsies were taken during radical prostatectomies. Transverse sections were performed and examined histologically. RESULTS: Certain nerves, derived from the neurovascular pedicle of the inferior hypogastric plexus, cross the rectovesical fascia to innervate the prostate. CONCLUSION: This confirms the importance of complete resection of the rectovesical fascia during radical prostatectomy for cancer, not only for surgical reasons, but also to ensure oncologically satisfactory surgery, i.e. with healthy resection margins.

Aged↗
PubMed2000

[Features of prostatic cancer in French individuals of African-Caribbean origin].

OBJECTIVES: To evaluate the clinical, laboratory and histological characteristics of prostate cancer at the time of diagnosis and after radical treatment in various ethnically different patient groups. PATIENTS AND METHODS: Prostatic biopsies were performed in 466 consecutive patients because of an abnormal digital rectal examination and/or isolated elevation of PSA (greater than 3 ng/ml). In this series, 40 patients were Black and 426 were Caucasian. The other aspect of the study concerns 320 patients undergoing radical prostatectomy for stage T1 T2 prostatic tumour (25 Black, 295 Caucasian). In the biopsied group, we analysed mean age, mean PSA, mean cancer length on biopsies and mean Gleason score. In the operated group, we studied preoperative characteristics, histological stage, resection margin status, laboratory progression (PSA greater than 0.05 ng/ml) and time to progression. RESULTS: At the time of diagnosis, the mean age was 61.4 years (48-73) for Blacks and 65.2 years (42-87) for Caucasians (p < 0.05). The median Gleason score was 7 in the two groups. The PSA was 13.4 (1.7-105) ng/ml versus 14.4 (0.4-600) ng/ml, respectively. The mean percentage of invaded tissue on biopsies was 24% versus 18.8% and the mean percentage of positive biopsies was 53% versus 39%, respectively. In the operated group, capsular effraction rates were 39% in Blacks and 48.1% in Caucasians. Positive resection margin rates were 21.7% versus 36.6%, respectively. The laboratory progression rate with a mean follow-up of 33 months (6-126) was identical in the 2 groups (42.1% versus 41.1%), but the time to progression was shorter for Blacks (9 months versus 12.3 months). CONCLUSIONS: In this patient series, Black patients had the same laboratory profile as Caucasian patients at the time of diagnosis. However, they were younger at the time of discovery of the disease, had more positive biopsies and more tumour-invaded tissue on biopsies, and Black patients undergoing radical prostatectomy developed laboratory recurrence more rapidly.

Aged↗
PubMed2000

Extensive biopsy protocol improves the detection rate of prostate cancer.

PURPOSE: We evaluated improvement in the rate of prostate cancer detection when using an extensive biopsy protocol involving peripheral cores. MATERIALS AND METHODS: We prospectively evaluated 303 consecutive men who underwent transrectal ultrasound guided biopsy due to elevated prostate specific antigen (PSA) and/or abnormal digital rectal examination. Ten biopsies were performed, including at least 5 at the base and middle of each lobe. In addition to standard biopsy at a 45-degree angle, a more peripheral 30-degree angle biopsy was obtained. At the apex only 1 standard biopsy was done. However, when prostate volume was greater than 50 cm.3, an additional peripheral biopsy was obtained at the apex. RESULTS: The complication rate in this biopsy protocol was 1% (3 patients). Prostate cancer was detected in 118 of the 303 men (38. 9%). Overall this extensive protocol resulted in 6.6% improvement in the detection rate. Improvement was 6.5% in men with PSA 10 ng./ml. or less and 7% in those with PSA greater than 10 (not significant). CONCLUSIONS: Increasing the number of biopsy cores and improving prostate peripheral zone sampling resulted in a significant improvement in the detection of prostate cancer.

Adult↗
PubMed2000

[Plastic surgery of the penis after circumcision].

One of the possible complications of circumcision is excessive resection of penile skin. This technical note describes two penile plasty techniques using scrotal skin after excessive circumcision.

Circumcision, Male↗
PubMed2000

[Does ureteroscopy still play a role in the treatment of ureteral calculi?].

OBJECTIVES: To evaluate the results obtained by ureteroscopy to treat ureteric stones and the related complications. MATERIALS AND METHODS: 74 ureteroscopies were studied retrospectively, including 62 cases of pelvic ureteric stones. In situ fragmentation was necessary in 28.4% of cases. Success was defined as the absence of stones for one month after ureteroscopy. Success rates were analysed according to size and site of the stone, the need for fragmentation and the patient's sex. RESULTS: Morbidity was 6.8%. Success was obtained in 60.8% of cases: 72.7% in women and 55.8% in men. The mean diameter of successfully treated stones was statistically smaller (6.2 +/- 2.1 mm) than that of stones with a poor result (7.8 +/- 3.7 mm) (p = 0.044, Spearman). CONCLUSIONS: The size and site of the stone and the patient's sex influence the results of ureteroscopy. Ureteroscopy for stone disease remains a topical modality after failure of extracorporeal lithotripsy, but also in the case of poor access of an effective lithotriptor.

Adult↗