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F M Debruyne

Publications and source records attributed to F M Debruyne.

At least 73 records · Page 4Linked to original sources
PubMed1999

Kidney cancer mortality in The Netherlands, 1950-94: prediction of a decreasing trend.

BACKGROUND: Incidence and mortality rates of kidney cancer are known to be increasing world-wide. The reasons for these increases are not clear, but despite this it may still be possible to predict changes in the trend of occurrence. METHODS: Male and female kidney (plus ureter and urethra) cancer mortality per 10(5) person-years, from 1950 to 94, were calculated using national demographic and mortality data. Changes in the age structure of the Dutch population were adjusted using direct standardisation to the European standard population. The effects of age, calendar period and birth cohort on the temporal trend in mortality were evaluated using log-linear modelling. RESULTS: Male mortality from kidney cancer increased from three per 10(5) person-years in the 1950s to eight per 10(5) in the mid 1980s and remained relatively stable thereafter. Female mortality rates showed a comparable trend, from two per 10(5) in the 1950s to four per 10(5) in the 1980s. In addition to the effects of age, the temporal trend in males can be sufficiently explained as a birth cohort effect. Successive birth cohorts appear to have higher risks of dying from kidney cancer until the 1930 cohort. The younger birth cohorts appear to have lower risks. The trend in women is comparable to that in men but is less pronounced and shows only after excluding women under the age of 45. CONCLUSION: The decreasing risk for generations born after 1930 will probably result in a decreasing trend in kidney cancer mortality in the near future. It is suggested that at least part of this changing trend in men (but not in women) is caused by the changing smoking behaviour of the Dutch population.

Adolescent↗
PubMed1998

Identification of intermediate cell types by keratin expression in the developing human prostate.

BACKGROUND: The secretory acini of the adult human prostate contain basal, luminal, and intermediate types of exocrine cells. Intermediate cells are thought to play an important role in normal growth and neoplastic transformation. In this study we investigated whether this cell type is present in early stages of prostate development, using keratin antibodies specific for them. METHODS: Autoptic tissue from 11 prepubertal and 5 normal adult prostates was immunohistochemically stained with four keratin antibodies capable of specifically detecting basal, luminal, or intermediate cell types. RESULTS: Morphologically, in fetal prostate cells differentiation was often not evident. However, basally located cells usually displayed a basal-cell keratin-phenotype. Morphologically similar cells with more luminal localization expressed keratins typical of luminal cells, or of intermediate cells. CONCLUSIONS: 1) In early stages of prostate development, cells with intermediate keratin-phenotype can be identified. 2) Their large numbers comply with a hierarchical pathway of cellular differentiation from basal to luminal cells. 3) The presence of intermediate cells at such an early fetal age may reflect their regulatory function in prostate development.

Adult↗
PubMed1998

A computer model of the neural control of the lower urinary tract.

Better understanding of the underlying working mechanism of the neural control of the lower urinary tract will facilitate the treatment of dysfunction with a neurogenic cause. We developed a computer model to study the effect of a neural control system on lower urinary tract behavior. To model the mechanical properties and neural control, assumptions had to be made. These assumptions were based, as much as possible, on knowledge and hypotheses taken from the literature. With valid assumptions, it should be possible to simulate normal as well as pathological behavior. To test the computer model, first, normal behavior of the lower urinary tract was simulated, and secondly, the known features of bladder outlet obstruction were simulated after the properties of the urethra were changed. The simulation results are comparable with measured data, so the assumptions on which the model is based could be valid. If the assumptions are valid, the feedback loops used in the model are also important feedback loops in vivo, and the model can be used to gain insight into the underlying mechanism of neural control.

Computer Simulation↗
PubMed1998

Automated image analysis for bladder cancer.

The genetic and epigenetic changes that occur during cancer development result in apparent morphological changes. Light microscopic image analysis provides objective assessment of cellular and nuclear morphology. The complexity of changes reflects the basic nature of dedifferentitation: a multi-hit process. Image analysis methods proved valuable for the assessment of malignancy in bladder cancer. Clinically applicable systems have been developed to diagnose urothelial cell cancer and predict prognosis. What is the place of these systems in daily practice?

Cell Nucleus↗
PubMed1998

Selective detrusor activation by sacral ventral nerve-root stimulation: results of intraoperative testing in humans during implantation of a Finetech-Brindley system.

Electrical sacral nerve-root stimulation can be used to induce bladder contraction. However, bladder emptying is hampered by simultaneous contraction of the external urethral sphincter. Voiding may improve when using a stimulation method that allows selective detrusor activation. Both theoretical and animal studies have demonstrated that it is possible to obtain selective detrusor activation by sacral root stimulation using an selective anodal block. The objective of this paper is to demonstrate the feasibility of this stimulation method in humans. For investigation of the stimulation method, intraurethral and intravesical pressure responses to sacral root stimulation were measured in acute experiments on 12 patients. The results show that selective detrusor activation is possible in patients. Future perspectives are discussed.

Electric Stimulation↗
PubMed1998

Long-term results of lower energy transurethral microwave thermotherapy.

PURPOSE: We evaluate long-term results of lower energy transurethral microwave thermotherapy (Prostasoft 2.0*) and identify pretreatment characteristics that predict a favorable outcome. MATERIALS AND METHODS: Between December 1990 and December 1992, 231 patients with lower urinary tract symptoms were treated with lower energy transurethral microwave thermotherapy. Subjective and objective voiding parameters were collected from medical records and a self-administered questionnaire. Kaplan-Meier plots were constructed to assess the risk of re-treatment. RESULTS: Of the patients 41% underwent invasive re-treatment within 5 years of followup and 17% were re-treated with medication. The re-treatment-free period was somewhat longer in patients with a peak flow rate greater than 10 ml. per second, a Madsen score 15 or less, a post-void residual volume 100 ml. or less and age greater than 65 years at baseline. Prostate volume did not modify the outcome. No incontinence was caused by transurethral microwave thermotherapy, 8% had recurrent urinary tract infection and 8% had retrograde ejaculation. Only 1 patient had a urethral stricture after transurethral microwave thermotherapy. CONCLUSIONS: At 5 years after transurethral microwave thermotherapy 41% of the patients received instrumental treatment. Patients with a lower Madsen score and lower residual volume, and those with higher peak flow and age were somewhat better responders to lower energy transurethral microwave thermotherapy.

Aged↗
PubMed1998

Edge detection in prostatic ultrasound images using integrated edge maps.

OBJECTIVE: We investigated an algorithm to detect grey level transitions with multiple scales of resolution to improve edge detection and localisation in ultrasound images of the prostate. INTRODUCTION: We had developed a non-analytical operator for prostate contour determination implemented with minimum and maximum filters and locate edges. We implemented a technique for improved determination of boundary parts in prostatic ultrasound images by adjusting the edge detection parameter to signal information. METHODS: First the influence of prefilter settings and edge detection parameters is investigated in a test image and a real ultrasound image. Then, local standard deviation is used to identify or fewer homogeneous regions that are filtered with course resolution, while areas with larger deviation that grey level transitions occur, which should be preserved using smaller filter sizes to improve edge localisation. RESULTS: Analysis of images with different filter sizes indicated that areas are merged for increasing filter sizes: less pronounced edges disappear or displace for larger filters. Two scales of resolution lead to an improved localisation of edges when smaller filter sizes are used in areas with an increased local standard deviation. CONCLUSIONS: This paper illustrates an edge detection method suitable as pre-processing step in interpretation of medical images. By adapting input parameters to signal information, object recognition can be applied in images from different imaging modalities. Also, disadvantages are discussed, resulting in a new application combining a localisation algorithm to find the initial contour and a delineation algorithm to improve the outlining of the resulting contour.

Algorithms↗
PubMed1998

Bladder wash cytology, quantitative cytology, and the qualitative BTA test in patients with superficial bladder cancer.

OBJECTIVES: Two new methods for the detection of transitional tumor cells in bladder wash (karyometry: QUANTICYT) and voided urine material (BARD BTA test) were compared with bladder wash cytology for the prediction of histology and tumor recurrence. METHODS: Bladder wash material and voided urine were sampled from 138 patients. Bladder wash karyometric (BWK) image analysis and the BTA test were applied. A subsequent urethrocystoscopy was performed and a bladder tumor, when present, was resected. Moreover, each patient was followed for tumor recurrence and progression. RESULTS: Sensitivities for the detection of tumors were 34.4%, 44.8%, and 69.0% for the BTA test, bladder wash cytology (BWC), and BWK, respectively (BTA versus BWC, P = 0.64; BTA versus BWK, P = 0.0002; BWC versus BWK, P = 0.0001, using the McNemar test). Specificities for the different tests were 81.3%, 92.5%, and 72.5%, respectively (BTA versus BWC, P = 0.096; BTA versus BWK, P = 0.031; BWC versus BWK, P = 0.001, using the McNemar test). Combinations of tests did not result in better prediction of the presence of tumor. Sensitivity of carcinoma in situ for the three tests was 0 of 3, 3 of 3, and 3 of 3, respectively. Follow-up analysis after a negative cystoscopy revealed comparable predictive values for BWC and BWK. CONCLUSIONS: The BTA test may be useful for patients with recurrent, low-grade papillary lesions. However, sensitivity for detection of these lesions, although higher than that for BWC, was only 42.9%. The highest specificity was found for BWC; however, this was accompanied by the lowest sensitivity of all three tests. The lower specificity of BWK was accompanied by a better prediction of tumor recurrence after a normal urethrocystoscopy. BWK is particularly sensitive for the recurrence of high-grade bladder lesions.

Carcinoma, Transitional Cell↗
PubMed1998

Impact of urometabolic evaluation on prevention of urolithiasis: a retrospective study.

OBJECTIVES: To obtain information on compliance to therapy and study its effect on recurrences. Over the past 20 years, a selective therapy protocol has been formed for prevention of urolithiasis recurrence. Many studies have been performed on the effectiveness of this therapy, but compliance has never been examined. METHODS: Data were abstracted from 177 medical records of patients who were seen at the outpatient clinic between 1985 and 1994. At that time, they were advised to follow a specific therapy regimen (high fluid intake, medication, and/or specific diet) on the basis of the outcome of a standardized metabolic evaluation. RESULTS: Thirty-six percent of the study population was still compliant to the prescribed therapy after a mean period of 5.3 years of follow-up. Therapy-compliant patients were older and had had more treatments, more lithiasis-related complaints, and more frequent follow-up visits. These characteristics suggest that patients' awareness of their disease might improve compliance. Survival analyses showed that patients can be classified into two groups characterized by the frequency of stone formation: a single stone episode versus frequent periods of stone formation. It appeared that the stone recurrence rate was twice as high among patients with a history of frequent stones compared with patients with a single stone episode, even though compliance to therapy seemed lower in the latter group. CONCLUSIONS: The usefulness of urometabolic evaluation and subsequent therapy advice seems questionable. Compliance to a life-long therapy is very low after a relatively short follow-up period. This study also suggests a prognostic classification based on stone rate.

Adult↗
PubMed1998

Long-term follow-up of an EORTC randomized prospective trial comparing intravesical bacille Calmette-Guérin-RIVM and mitomycin C in superficial bladder cancer. EORTC GU Group and the Dutch South East Cooperative Urological Group. European Organisation for Research and Treatment of Cancer Genito-Urinary Tract Cancer Collaborative Group.

OBJECTIVES: To determine long-term efficacy of intravesical mitomycin C (MMC) versus bacille Calmette-Guérin (BCG) in patients with superficial bladder cancer with regard to recurrences and progression. METHODS: Patients with superficial bladder cancer (pTa, pT1, pTis) were treated with intravesical MMC (30 mg, weekly for 4 weeks, and thereafter monthly for 5 months) or BCG (weekly for 6 weeks). RESULTS: Three hundred forty-four patients were eligible (171 in the BCG group, 173 in the MMC group). The median follow-up was 7.2 years. Toxicity was not significantly different between the two treatment groups. Efficacy of the two treatment policies was similar with regard to tumor recurrence. With regard to progression to invasive disease, MMC was more effective than BCG in patients without carcinoma in situ (CIS) (P = 0.006). CONCLUSIONS: We can confirm the conclusions of other studies that intravesical treatment with 30 mg of MMC remains an effective treatment option that can also be used in high-risk patients. Like others, we could not confirm that a 6-week course of BCG is more effective in the prevention of tumor progression. Of the 33 patients with tumor progression after intravesical therapy, 20 died of bladder cancer, confirming that tumor progression after intravesical therapy carries a poor prognosis. In this study the difference in toxicity between BCG and MMC was not significant. When comparing studies with MMC and BCG, differences in treatment schedule and/or patient selection should be kept in mind.

Adjuvants, Immunologic↗
PubMed1998

Immunohistochemical analysis of intratumoral heterogeneity of [131I]cG250 antibody uptake in primary renal cell carcinomas.

In previous studies, highly heterogeneous uptake of 131I-labelled chimeric monoclonal antibody G250 ([131I]cG250) in primary renal cell carcinomas has been observed (intratumoral differences > factor 100). In this study, we investigated a possible correlation between intratumoral antibody uptake and four immunohistochemically determined parameters: G250 antigen expression, blood vessel density, neovascularization and percentage of viable tumour cells. Whole tumour slices of four different tumours were cut into 1-cm3 cubes, and in each cube the [131I]cG250 uptake was determined. The correlation between [131I]cG250 uptake and each individual parameter was determined in a multiple regression analysis. Additionally, the data were reanalysed after introducing arbitrary cut-off values for each parameter. If a sample showed expression of a parameter above the introduced threshold value, this sample fulfilled one condition. Subsequently, the Pearson correlation coefficients were calculated from [131I]cG250 uptake and the number of fulfilled conditions (0-3). All tumour samples with high [131I]cG250 uptake [> 0.1% of the injected dose per gram (ID g(-1))] showed high antigen expression (> 50%). However, not all samples with high antigen expression displayed high uptake. A statistically significant correlation between [131I]cG250 uptake and antigen expression was found (beta = 0.44, 0.69 and 0.74) in three out of four tumours analysed. Of the other determined parameters, no consistent correlation with [131I]cG250 uptake was found; only the percentage of viable tumour cells correlated significantly in two out of four tumours (beta = 0.80 and 0.26). Calculation of the Pearson correlation coefficients showed a statistically significant correlation between [131I]cG250 uptake and an increased number of fulfilled conditions in all tumours, indicating that each of the individual parameters contribute to the uptake of [131I]cG250. These observations indicate that high antigen expression is a prerequisite for high antibody uptake. However, regional differences in antibody uptake within a tumour cannot be explained by antigen expression alone.

Antibodies, Monoclonal↗
PubMed1998

Treatment of mid- and lower ureteric calculi: extracorporeal shock-wave lithotripsy vs laser ureteroscopy. A comparison of costs, morbidity and effectiveness.

OBJECTIVES: To determine the efficacy and costs of extracorporeal shock-wave lithotripsy (ESWL) compared with ureteroscopy (URS) in the treatment of mid- and lower ureteric calculi. PATIENTS AND METHODS: The records of patients treated primarily by ESWL and URS were analysed retrospectively. Treatment with ESWL included 63 patients (42 men and 21 women, mean age 52 years, range 23-78, 19 mid- and 44 lower ureteric calculi). All patients received 4000 shock waves at a mean energy setting of 18.1 kV. URS was used in 105 patients, with a 7.2 F miniscope or the 7.1 F flexible scope. Stones were fragmented with a pulsed-dye laser lithotripter at 504 nm and a power of up to 130 mJ (mean 53 mJ) using a 200 or 320 microns fibre. All ureteroscopies were performed with the patient under general (n = 17) or spinal (n = 87) anaesthesia in a mean treatment duration of 34 min. Stones were located in the mid-ureter in 24 patients and in the lower ureter in 80. The outcome was assessed by stone-free rates, re-treatment rates, time to become stone-free, complication and costs. RESULTS: ESWL for mid- and lower ureteric calculi resulted in a success rate of 90% and 81%, respectively, compared with 96% and 99% for URS. However, patients treated with URS were stone-free within 2 days, whereas patients in the ESWL group required up to 4 months. The best results for ESWL were achieved with stones of < 50 mm2. The costs of URS were higher than those for ESWL. CONCLUSIONS: ESWL provides a noninvasive, simple and safe option for the management of mid- and lower ureteric calculi, provided that the stones are < 50 mm2; larger stones are best treated by URS.

Adolescent↗
PubMed1998

Transurethral resection of the prostate vs high-energy thermotherapy of the prostate in patients with benign prostatic hyperplasia: long-term results.

OBJECTIVE: To evaluate the outcome and durability of high-energy transurethral microwave thermotherapy (HE-TUMT) in comparison with transurethral resection of the prostate (TURP). PATIENTS AND METHODS: Fifty-two patients with BPH and lower urinary tract symptoms were randomized and treated either by TURP (21 patients; mean prostate volume 45 mL, SD 15) or HE-TUMT (31 patients, mean prostate volume 43 mL, SD 12). Long-term results were obtained at a mean (SD) follow-up of 2.4 (0.5) years. RESULTS: During the follow-up, the mean symptomatic improvement stabilized at 56% after TUMT and 74% after TURP. The mean maximum urinary flow rate increased by 62% after TUMT and 105% after TURP. Before treatment, 78% of patients in the TURP group were obstructed according to urodynamic investigation and after treatment, 14% remained obstructed. In the TUMT group, 67% of patients were obstructed before treatment and 33% remained so afterward. Six patients (19%) underwent TURP after TUMT (four after 1 year) and two patients were also treated with medication. One patient underwent a bladder neck incision after TURP to treat bladder neck sclerosis. Three patients were not satisfied with the outcome after the additional TURP. CONCLUSION: Both treatment modalities show good symptomatic and objective results at > 2 years of follow-up. Most re-treatments were performed > or = 1 year after treatment and were based on subjective findings.

Aged↗
PubMed1998

Expression of periglandular tenascin-C and basement membrane laminin in normal prostate, benign prostatic hyperplasia and prostate carcinoma.

OBJECTIVE: To evaluate the structural relationship of the distribution between tenascin (tenascin-C, an extra-cellular matrix glycoprotein involved in stromal-epithelial interactions in both normal and pathological conditions) and laminin, an important component of the basement membrane, in normal and neoplastic human prostate, and to establish whether changes in the basement membrane are accompanied by changes in tenascin staining. MATERIALS AND METHODS: Seventy-five snap-frozen prostate samples representing normal glands, nodular benign prostatic hyperplasia and prostate carcinoma were stained for tenascin. From these, 15 samples were selected for dual-immunofluorescence staining and a confocal laser scan microscope was used to simultaneously visualize tenascin and laminin immunoreactivity. RESULTS: Tenascin was expressed in the extracellular matrix, mainly at the periphery of the glands, in tumour foci and blood vessels. In cases with intact basement membranes, e.g. normal glands and hyperplastic lesions, tenascin expression was weak. Low- and moderate-grade tumours were characterized by strong tenascin expression, while laminin expression was weak and/or showed discontinuities, indicating disturbances in basement membrane composition. High-grade tumours had sparse tenascin staining and a marked loss of laminin immunoreactivity. CONCLUSION: These results indicate that periglandular tenascin expression correlates with the integrity of the basement membrane in the human prostate. By influencing stromal-epithelial interactions, tenascin may play a role in maintaining tissue homeostasis in the prostate.

Basement Membrane↗
PubMed1998

The predictive value of baseline variables in the treatment of benign prostatic hyperplasia using high-energy transurethral microwave thermotherapy.

OBJECTIVE: To evaluate the combination of patient age, prostate size, grade of outlet obstruction and total amount of energy, all independent predictive variables of treatment outcome in patients with lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia (BPH) treated with high-energy transurethral microwave thermotherapy (HE-TUMT), and thus provide nomograms for predicting treatment outcome after HE-TUMT. PATIENTS AND METHODS: Between October 1993 and July 1996, 247 patients with LUTS and BPH were treated with HE-TUMT using the Prostatron device, software version 2.5 (EDAP Technomed, Lyon, France). The World Health Organisation Response Evaluation Criteria were used to evaluate the outcome. Patient age, prostate volume, total amount of energy and grade of outlet obstruction were categorized using the Akaike information criterion (AIC). The probabilities of a good/intermediate vs a poor response at 26 weeks according to the AIC were calculated. RESULTS: Nomograms are presented providing the estimated probability (95% confidence interval) for a good/intermediate response of the evaluation of the International Prostate Symptom Score at 26 weeks by categories of prostate volume, total amount of TUMT energy and age, and of maximum urinary flow rate by categories of bladder outlet obstruction (linear passive urethral resistance ratio, linPURR) and total amount of energy, and of linPURR by categories of prostate volume and total amount of energy. The total amount of energy appeared to have the most impact in the prediction of good/intermediate and poor response in all three response evaluation criteria. CONCLUSIONS: These nomograms may assist urologists in making clinical recommendations for the treatment of men with LUTS and BPH using HE-TUMT.

Adult↗
PubMed1998

Tumor retention of 186Re-MAG3, 111In-DTPA and 125I labeled monoclonal antibody G250 in nude mice with renal cell carcinoma xenografts.

UNLABELLED: In radioimmunotherapy of solid tumors substantial gain might be achieved by carefully selecting the radionuclide and the linker connecting it to the antibody. In contrast to 131I, radiometals such as 90Y and 111In may be retained in the tumor cell after internalization of the antibody, thereby enhancing the radiation dose to the tumor. The physical properties of 186Re with 1.08 MeV beta-emission (71%) and 137 keV gamma-emission (10%) seem ideal for radioimmunotherapy. In this study we investigated in nude mice with s.c. renal cell carcinoma xenografts the biodistribution and the retention in the tumor of 186Re-MAG3 labeled monoclonal antibody (mAb) G250 as compared to 111In-DTPA-G250, to 125I-G250 and to 131I-MN14 (non-specific control mAb). Radiolabeled antibody preparations were i.v. injected. Seventy two hours p.i. the biodistribution of the radiolabel was determined. Blood levels of all mAb G250 preparations were remarkably low (mean: 2.38, 1.40 and 1.43% ID/g for 125I, 111In and 186Re respectively) whereas blood levels of mAb MN14 were significantly higher (mean: 12.3% ID/g), indicating tumor processing of mAb G250. Retention of 111In in the tumor was significantly higher than of 186Re and 125I whereas retention in the tumor of 186Re and 125I did not differ significantly. CONCLUSION: In contrast to other radiometals such as 111In and 90Y, 186Re is not retained in the tumor cell. Therefore 186Re has no additional advantage for radioimmunotherapy with respect to retention in the tumor.

Animals↗
PubMed1998

Influence of decay of laser fibers during laser prostatectomy on clinical results.

Three types of sidefiring laser fibers (34 Urolase, 20 Ultraline, and 114 Prolase II) were visually inspected after a laser prostatectomy, and transmission measurements were performed using a power meter (Aquarius). The results were correlated with the clinical outcome. Despite differences in the amount of loss in transmission for the fibers used, we could not establish any significant effect on clinical outcome measures, such as improvement in maximal flow rate or symptom score. The visual aspect of the Urolase fibers was significantly related to the amount of transmission loss, whereas no such relation was found for the other two types of fibers. Prostate size and the total amount of energy delivered by the laser source also did not correlate with the clinical outcome. To determine the relation between the energy absorbed by the prostate and clinical outcome, a large number of patients must be evaluated, and any factor that can be controlled needs to be monitored. For the latter, the power meter as presented here is a useful complementary tool.

Diuresis↗