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K J Tveter

Publications and source records attributed to K J Tveter.

At least 19 recordsLinked to original sources
PubMed2001

The effect of bicalutamide on prostate histology.

BACKGROUND: Nonsteroidal antiandrogens are commonly used in the treatment of prostate cancer, but more clinical and laboratory studies on patients with benign as well as malignant prostate diseases are required to define their exact role. METHODS: Light microscopic examination of perineal prostate biopsies of 21 men with BPH was performed pretreatment, after 24 weeks of therapy with 50 mg bicalutamide (Casodex) or placebo and 24 weeks after end of treatment. We assessed whether it was possible to distinguish between patients having received bicalutamide or placebo based on a general histological examination. In addition, the volume fractions of the prostatic epithelial, luminal, and stromal compartments were determined by morphometry. RESULTS: Histological changes following treatment were uncharacteristic and patients treated with bicalutamide were not identified. At morphometry prior to therapy, the prostates of the study participants consisted of 91.8% stroma (range 78.9-97.2), 5.5% epithelium (range 1.4-14.1) and 2.7% glandular lumen (range 0.8-7.5). Changes in the relative content of the three tissue components following treatment were not statistically significant. CONCLUSIONS: We did not observe consistent morphological changes in the prostate following treatment with bicalutamide at a dose of 50 mg daily. However, this dose is lower than the 150 mg dose presently recommended for bicalutamide monotherapy.

Aged↗
PubMed1997

[Urosepsis].

Septicemia as a result of urinary infection is a serious condition, almost always caused by gram-negative bacteria. The bacterial toxins have a profound influence on haemostasis, microcirculation, and cardiac anf respiratory function. This article contains a brief review of aetiology, pathogenesis, pathophysiology, diagnostic work-up and treatment of this life-threatening condition. As soon as specimens from urine and blood are sent for bacteriological examination, intravenous antibiotics are given. It is essential that free drainage of urine from both kidneys is established by means of a bladder catheter, retrograde catheterization or percutaneous nephrostomy. The development of septic shock is a life-threatening condition which should be treated in an intensive care unit with continuous monitoring of vital parameters.

Humans↗
PubMed1997

[Maximal androgen blockade in metastatic prostatic carcinoma].

In Norway the standard treatment for metastatic prostatic cancer has been surgical or medical castration. Only recently have antiandrogens been approved for treatment of advanced cancer of the prostate. The authors examine the principles for total or maximal androgen blockade and discuss American and European studies that indicate an improvement in survival as a result of maximal androgen blockade therapy in patients with low volume disease and good performance. Though not yet statistically proven in prospective trials, it is recommended that such patients should be given maximal androgen blockade therapy, also in Norway.

Androgen Antagonists↗
PubMed1997

Prognostic factors in patients with metastatic (stage D2) prostate cancer: experience from the Scandinavian Prostatic Cancer Group Study-2.

PURPOSE: Nuclear texture reflects the overall structures of the chromatin organization. We recently reported the principles and prognostic importance of image analysis of nuclei from metastatic prostate cancer. Immunohistochemical up regulation of the adhesion molecule sialyl Lewis(x) is also reported to be a prognostic parameter. Presently we analyzed statistically the prognostic impact of these 2 new parameters compared to well-known clinical parameters in metastatic prostate cancer. MATERIALS AND METHODS: Prognostic factors, such as sedimentation rate, alkaline and acid phosphatases, hemoglobin, testosterone, performance status, pain due to metastasis, T category, histological grade and patient age, were included in a multivariate Cox proportional hazards regression analysis based on 262 patients from the Scandinavian Prostatic Cancer Group Study-2. Extent of bone lesions, deoxyribonucleic acid ploidy, texture analysis and sialyl Lewis(x) molecules based on subsets of these 262 patients were also analyzed in the same multivariate model. RESULTS: This test identified chromatin texture as the most important factor (p < 0.001), followed by reaction of the oligosaccharide sialyl Lewis(x) (p < 0.01). Among the routine clinical and laboratory data, sedimentation rate, alkaline phosphatase and hemoglobin (p < 0.05) showed prognostic importance. Performance status, pain due to metastasis and extent of bone lesions showed prognostic value in the univariate analysis (p < 0.05). CONCLUSIONS: These data indicate that computerized nuclear texture analysis as well as up regulation of sialyl Lewis(x) molecules may be new important prognostic factors in metastatic prostate cancer. Furthermore the prognostic importance of sedimentation rate, alkaline phosphatase and hemoglobin was confirmed.

Aged↗
PubMed1997

Treatment of benign prostatic hyperplasia. A pharmacoeconomic perspective.

Men with moderate symptoms of benign prostatic hyperplasia (BPH) are the best candidates for medical treatment, while surgery is usually indicated for patients with severe symptoms. Men with mild symptoms do not usually need treatment, but they might be re-evaluated annually if desirable. Finasteride, which produces selective hormonal deprivation, is now established as a well tolerated drug for the long term medical therapy of BPH. Recent studies suggest that finasteride is most effective in men with large prostates (> 40 ml), and the drug should probably be reserved for these patients. alpha-Blockers work in men with small or large prostates, and their rapid onset of action facilitates the identification of responders. alpha-Blockers are more effective than finasteride during the first year of treatment, but only finasteride induces regression of the prostate and offers increased efficacy over time. Even if drug therapy reduces the need for prostate surgery, the total economic cost of BPH treatment is likely to rise because of the increasing application of medical treatment. The magnitude of this increase depends largely on what percentage of the male population embark on long term therapy, at what age treatment is started, and how successful it is. At present, the answers to these questions are largely unknown. The personal economic expenses for men who begin long term medical therapy will probably be an important factor in deciding how common drug treatment for BPH will become in the future. For many men, the main benefit of drug treatment will be the relief of urinary symptoms, but whether this improvement is substantial enough to improve their overall quality of life has not yet been clearly demonstrated in controlled studies.

Adrenergic alpha-Antagonists↗
PubMed1996

[Treatment of benign prostatic hyperplasia with Proscar (finasteride). Results of a 10-year Scandinavian study].

707 patients with moderate prostatic hyperplasia were recruited to a two-year Scandinavian multicenter study. The study was randomized, prospective and double-blind. Half of the patients were treated with finasteride (5 mg daily) and the controls were given placebo. The patients were monitored with regard to symptoms, urinary flow rate and prostate volume. In addition, various laboratory examinations were performed. A statistically significant difference was found between the groups with regard to symptom improvement and increase in urinary flow rate in favour of finasteride. Finasteride reduced prostate volume and stopped further growth, leading to a difference of 30% in prostate volume between the two groups after two years of treatment. Thus, finasteride was able to stop the continuous growth of the prostate in the elderly male. The proportion of patients with adverse clinical experiences was similar in both treatment groups. However, the finasteride-treated group contained more patients with sexual dysfunction. We conclude that finasteride is an alternative to vigilant waiting for patients with moderate symptoms of benign prostatic hyperplasia.

Aged↗
PubMed1996

[Diagnosis and treatment of benign prostatic hyperplasia in general practice. Norwegian Medical Society].

The prevalence of benign prostatic hyperplasia increases with increasing age. The growing number of elderly men in the population will cause a marked increase in the number of men suffering from this condition. The magnitude of the problem necessitates close cooperation between urologists and general practitioners in future in order to take care of patients with benign prostatic hyperplasia. The purpose of the present survey is to present guidelines for general practitioners to enable them to diagnose this condition and to present the various alternative treatments currently available. Patients with mild and modest symptoms do not need to be referred to an urologist and can be taken care of by the general practitioners themselves.

Diagnosis, Differential↗
PubMed1996

Entropy-based texture analysis of chromatin structure in advanced prostate cancer.

A new texture operator, gray-level entropy matrix (GLEM), was developed, and nine new textural features were extracted from this matrix. These textural features were applied to light microscopy images of nuclei taken from monolayers of advanced prostate cancer cells representing two different prognostic groups: hormone-sensitive (good prognosis) and hormone-resistant (poor prognosis) tumors. A comparison between the classification results obtained from GLEM features and those obtained from standard textural estimators is also discussed. Single features that gave correct classification rates better than 65% were included in a discriminant analysis in order to find the optimal set of features to discriminate between the two prognostic groups in the training data set. The best combination of features includes three GLEM features together with ENTROPY extracted from gray-level cooccurrence matrix, and this combination gave a correct classification rate of 95% using the leaving-one-out technique. The influences of image sharpness and number of cells were also investigated. The features based on entropy or degree of scatter of minute structures can be used to discriminate between hormone-sensitive and hormone-resistant prostate carcinomas.

Cell Nucleus↗
PubMed1996

Nuclear texture analysis: a new prognostic tool in metastatic prostate cancer.

This report describes the prognostic value of computerized nuclear texture analysis in metastatic prostate cancer. Seventy-seven patients with histologically verified prostate carcinomas and skeletal metastases were selected from a Scandinavian multicenter study (SPCG-2). Thirty-six therapy-resistant patients experienced objective progression and cancer-related death within 2 years after orchiectomy. Thirty patients responded well to orchiectomy, i.e., showed objective disease remission and no signs of progression during 3 years of follow-up. From this data set, 10 randomly chosen therapy-resistant and 10 randomly chosen therapy-sensitive carcinomas were used in our previous study to find the optimal combination of features that can discriminate between the two groups (Yogesan et al.: Cytometry 24:268-276, 1996). In addition to these two groups, 11 patients experienced stable disease or disease remission during the first year and a secondary progression during the second or third year of follow-up, with subsequent cancer-related death. Traditional clinical prognostic factors such as histopathological grading and serum markers could not discriminate between these groups of patients. Therefore, image analysis techniques based on texture analysis have been utilized in this study of prognosis of prostate cancer. Feulgen-stained monolayers of nuclei were prepared from paraffin-embedded material taken from the primary tumor before endocrine ablation. Four different textural features were selected from the training data set to calculate the discriminating function. This function separated the therapy-sensitive and the therapy-resistant patients with 87% accuracy in the independent data set. This study demonstrates that it is possible to predict tumor progression and survival for endocrine-ablated metastatic prostate carcinomas using computerized nuclear texture analysis on light microscopy images from prostate biopsies taken at the time of diagnosis.

Aged↗
PubMed1996

Effects on the endocrine system of long-term treatment with the luteinizing hormone-releasing hormone agonist leuprolide in patients with benign prostatic hyperplasia.

Hormonal changes resulting from long-term use of the luteinizing hormone-releasing hormone agonist leuprolide depot were studied in a randomized placebo-controlled study comprising 50 evaluable patients with benign prostatic hyperplasia (BPH). A total of 26 patients received 3.75 mg leuprolide depot intramuscularly every 28 days for 24 weeks and 24 received a placebo. The patients were followed up for a further 24-week period. Serum concentrations of luteinizing hormone decreased by 90% and follicle-stimulating hormone by 55% during the treatment period. Mean testosterone levels decreased by 96% to 0.7 nmol l-1 and dihydrotestosterone decreased by 90%. The adrenal androgens androstenedione and dehydroepiandrosterone sulphate decreased by 48 and 24%, respectively. In most patients, estradiol decreased to non-detectable values, while the decrease in estrone was 35%. There was no change in prolactin and sex hormone-binding globulin as compared to the placebo group. Hormonal changes were reversible, but the suppression of testicular hormone production was not completely normalized in all patients 24 weeks after discontinuation of the treatment.

Aged↗
PubMed1996

Morphometry of benign prostatic hyperplasia during androgen suppressive therapy. Relationships among epithelial content, PSA density, and clinical outcome.

We performed light microscopic morphometry on prostate biopsies of 41 patients who underwent androgen suppressive therapy for 24 weeks with the luteinizing hormone releasing hormone (LHRH) agonist leuprolide depot for symptomatic benign prostatic hyperplasia (BPH). Before treatment started, the prostates consisted of 88.4% stroma, 9.0% epithelium and 2.6% glandular lumen. After completion of therapy, the percentages were 94.7, 3.0 and 2.3, respectively. The absolute reductions of volume were 27% for stroma, 77% for epithelium and 40% for lumen. Correlations between pretreatment parameters (epithelial content, stromal epithelial ratio and prostate specific antigen density (PSAD)) and the clinical outcome parameters (prostate volume reduction, improvement in maximum flow rate, reduction of symptom score and reduction in outflow resistance) were not statistically significant, indicating that the histological composition of BPH tissue or PSAD are poor parameters to predict differences in response for individual patients during hormonal therapy for BPH. By comparing morphometry results of the core biopsies with morphometry performed on corresponding TURP tissue, it appeared that the lumen content of the biopsies was somewhat underestimated.

Aged↗
PubMed1996

Scanning electron microscopy of the accessory sex glands of the adult male rat.

This study describes the morphology of the accessory sex glands of the adult male rat as observed by scanning electron microscopy (SEM). The purpose was to obtain a systematic and comparative SEM description of these glands and to evaluate different preparation techniques. A common morphological feature is polyhedral delineation of the cells, which exhibited a variable convexity of their apical surface. The cell apices were more or less studded with microvilli. Nevertheless, it was possible to distinguish the glands by their surface morphology. In the ventral prostate, there was a considerable heterogeneity in cell surface appearance. The lateral lobe had a characteristic brush border, and in the dorsal lobe, surface blebbing and intracellular cisternae were observed. The cells of the seminal vesicle were covered by long microvilli, while particularly distinct, elevated cell borders and intracellular cisternae were typical for the coagulating gland. The secretory mechanism was merocrine in the ventral and lateral prostate and the seminal vesicle, and was mainly apocrine in the dorsal prostate. Surprisingly, only merocrine secretion was obvious in the coagulating gland. The most controversial observation, which needs further investigation, was the discovery of large orifices in the apical surface of individual seminal vesicle cells. These orifices may be indicative of an additional apocrine secretion in this gland. In studying this organ system, SEM provides information that adds to previous transmission electron microscopical investigations.

Animals↗
PubMed1996

Effects of castration upon the morphology of the accessory sex organs of the male rat--a scanning electron microscopy study.

A systematic, comparative study of the accessory sex glands of the adult male rat after androgen withdrawal was carried out. The changes were investigated by using scanning electron microscopy at different intervals after surgical castration. The main common signs of epithelial cell involution were flattening of the cell surface, reduction of the size and number of microvilli, some blurring of the cell borders, cessation of secretory activity and diminution of the luminal volume of the glands. Overall, confident signs of atrophy were evident after one week, and complete epithelial involution was reached by the third week. The epithelial cell atrophy was accompanied by a relative stromal hyperplasia. The new observation seems to be that the process of stroma consolidation is progressing for a considerable time subsequent to the completion of the epithelial involution. This phenomenon is particularly evident in the dorsal prostate, the seminal vesicle and the coagulating gland.

Animals↗
PubMed1995

Up-regulation of the oligosaccharide sialyl LewisX: a new prognostic parameter in metastatic prostate cancer.

Metastatic prostate cancer has an unpredictable long-term prognosis. At present, there are few specific predictors to indicate the outcome for the individual patient. We have studied immunoreactivity for type-2 carbohydrate structures, known to be involved in various cell adhesion processes, in patients with metastatic prostate cancer. One group of patients (n = 26) did not progress within 3 years after orchiectomy, while another group of patients (n = 33) progressed within 1 year following castration and survived less than 2 years. Among the parameters studied, sialyl LewisX carbohydrate up-regulation was the only variable showing significant association with poor prognosis (P < 0.01). Sialyl LewisX discriminated between these two outcome groups with 71% predictability and 96% specificity. Our results indicate that up-regulation of sialyl LewisX is associated with hormonal-resistant, aggressive disease. This prognostic marker may, therefore, have an important role in selecting proper treatment for patients with metastatic prostate cancer.

Adenocarcinoma↗
PubMed1995

Histopathological grading and DNA ploidy as prognostic markers in metastatic prostatic cancer.

The present study compares the prognostic potential of tumour grade and DNA ploidy status in patients with advanced-stage prostatic cancer. Two outcome groups were selected on the basis of time to progression and survival after orchiectomy. A poor-outcome group consisted of 32 therapy-resistant patients who experienced disease progression during the first year after orchiectomy and subsequently death due to prostatic cancer during the following year. A good-outcome group consisted of 27 therapy-responsive patients who showed disease regression and no signs of progression during a 3 year follow-up. The primary tumours were graded twice according to WHO and Gleason classification systems by two pathologists. Final agreement between the pathologists was obtained after a consensus meeting. The analysis revealed no prognostic importance of the two histological classification systems (P = 0.62 and P = 0.70) and disclosed weak inter- and intra-observer reproducibility (kappa < 0.70). DNA ploidy analyses were performed by image cytometry on formalin-fixed, paraffin-embedded samples of the primary tumours. Overall, 48% of the tumours were diploid, 20% tetraploid and 32% anueploid. DNA ploidy status did not discriminate between the two outcome groups (P = 0.46). Histological grade and DNA ploidy showed no prognostic importance in patients with prostatic cancer and skeletal metastases.

Adult↗