Search PubMed⌕ Search

Biomedical subjects

G R Prout

Publications and source records attributed to G R Prout.

At least 163 records · Page 9Linked to original sources
PubMed1976

In vitro uptake of 3H testosterone and its conversion to dihydrotestosterone by prostatic carcinoma and other tissues.

Needle biopsies of normal, benign hyperplastic, neoplastic and metastatic prostatic tissues were used to study the uptake of 3H testosterone by these tissues and their ability to convert testosterone to dihydrotestosterone. Histological quantification is important because stroma is active in both of these areas of biochemical activity. The 3H testosterone uptake by the tissues is relatively similar but benign prostatic hyperplasia and normal tissue consistently convert more testosterone to dihydrotestosterone than do neoplastic tissues. The least active in this regard are pure biopsies of neoplastic cells obtained from nodal metastases, suggesting extensive loss or repression of 5-alpha-reductase activity. Further, this defect is present in neoplastic tissues even if the patient has had an orchiectomy and/or received hormonal therapy. It is not known whether testosterone may substitute for dihydrotestosterone in the neoplastic nucleus. Our studies indicate that animal models that yield data on suppresion of 5-alpha-reductase activity by certain agents may have limited relevance to the tissues of human prostatic carcinoma.

Aged↗
PubMed1976

Retroperitoneal fat necrosis producing ureteral obstruction.

We present 3 cases of a rare syndrome of extrinsic ureteral obstruction produced by retroperitoneal fat necrosis and compare the medical records and histopathology to 19 cases of classic idiopathic retroperitoneal fibrosis. Clinical similarities include average age of onset in the fourth and fifth decades, male preponderance, abdominal or back pain as the presenting symptom, elevation of the blood urea concentration prior to diagnosis and tendency toward bilateral involvement. Histologically, the 2 conditions were different. Retroperitoneal fat necrosis is characterized by coalescence of fat cells into fat cysts bordered by foreign body giant cell granulomas, foam cells, light chronic inflammatory infiltrate and unimpressive fibrosis. The microscopic pathology of idiopathic retroperitoneal fibrosis is dominated by densely collagenized fibrous tissue of varying cellularity without evidence of fat necrosis. Of the 3 cases of retroperitoneal fat necrosis 2 featured prior ischiorectal abscesses and this is considered in a discussion of the etiology of this unusual cause of ureteral compression.

Adipose Tissue↗
PubMed1976

The continued evaluation of the effects of chemotherapy in patients with advanced carcinoma of the prostate.

The response and duration of survival were evaluated for patients with stage D relapsing prostatic cancer who were randomized to cyclophosphamide (Cytoxan),5-fluorouracil (5-FU) or standard therapy, or to subsequent chemotherapies. The chemotherapies on initial randomization were superior to the standard therapy in the number of responders and duration of response. Survival was longer for responders (stable or partial regression) on chemotherapy by comparison to responders (stable only) on standard therapy. The survival for patients receiving initial and crossover chemotherapy was significantly improved for patients who responded to therapy. Chemotherapy of advanced relapsing stage D prostatic cancer is more beneficially treated by specific chemotherapy as shown in this randomized study.

Carcinoma↗
PubMed1976

A new look at bladder neck obstruction by the food and drug administration regulators: guide lines for investigation of benign prostatic hypertrophy.

A basic assumption of current guide lines to test drug therapy for benign prostatic hypertrophy is that the clinical disease is caused by bladder neck obstruction and its sequelae and complications. Asymptomatic non-prostatic hypertrophy, no matter how large the adenoma, is considered to be a pre-clinical phase of the disease as long as bladder trabeculation, impairment of the flow rate and residual urine are absent. The guide lines recognize that histological changes and gross anatomical enlargement of the prostate are the essence of the disease but objective signs of current therapeutic relief of symptoms lend themselves more practically to measurement of progression or remission, whereas no current drug has a clear enough effect on prostatic histology to predict subsidence of the clinical picture. Since no one criterion or single test serves this purpose a cluster of symptoms, with flow rate and residual urine, provides the hardest data. It would be preferable for each patient to serve as his own control in a prospective double-blind randomized study, since the literature shows no uniformity of approach, methodology, patient population or other useful data for clinical norms. Guide lines have been developed with the aid of clinical pharmacologists, biostatisticians, lawyers and government officials and approved by the Food and Drug Administration. Misconceptions outside of the profession of Urology need to be dispelled and further research in methodology, urodynamics, ultrasonic evaluation of the prostate, definition of symptoms, criteria for efficacy, etiology of the disease, and mode of action of drugs, placebo and surgery were highlighted. The literature does not have an overabundance of data but does contain evidence of definite but weak drug efficacy in the treatment of this condition.

Diagnosis, Differential↗
PubMed1976

One-stage radical cystectomy for bladder carcinoma: operative mortality, cost/benefit analysis.

An analysis of cystectomies performed between September 1, 1969 and December 31, 1974 was conducted to determine the rates of morbidity (59 per cent) and operative mortality (4.1 per cent). Comparison of these figures for single operations with data published from other sources concerning staging of the therapeutic procedures suggests that there is no benefit for the patient relative to surgical morbidity or mortality if the latter course is followed. Conversely, prolongation of hospital experience, multiple operations, absence from productive activity and increased health care cost are associated with the staged procedures. Application of cost/benefit analysis suggests that this experience may act as a model to evaluate competing forms of therapy involving other disorders. When costs are not equivalent and benefits are the same the more expensive form of therapy should not be offered except for unusual circumstances.

Adult↗
PubMed1975

Lactic dehydrogenase isoenzymes in human bladder cancer.

The lactic dehydrogenase isoenzymic patterns of normal, atypical and neoplastic urothelium were studied. In comparison to normal, the atypical urothelium had a significant increase in the LDH-V/I ratio. In neoplastic urothelium the LDH-I per cent was increased in low grade tumors, while the LDH-V per cent and LDH-V/I ratio was increased in high grade tumors. The findings in high grade tumors are thought to represent altered genetic expression with activation of the gene locus controlling M subunit synthesis.

Biopsy↗
PubMed1975

Prostatic cancer and SCH-13521: II. Histological alterations and the pituitary gonadal axis.

We herein report on the results of treatment of 13 men with stage D prostatic carcinoma with a non-steroidal compound, SCH-13521 (flutamide). The dosage of the drug was 750 mg. in 3 divided doses daily and treatment extended for 2 to 20 months. Two patients failed to respond in any fashion, 7 had objective evidence of response and the others had varying degrees of subjective response. Plasma testosterone was never suppressed and sexual potency was not altered by the drug. Gynecomastia occurred in several patients, 1 patient had intractable vomiting and 2 had thromboembolic disease. In tissue biopsies after therapy, cytotoxic changes in some acinar cells were noted but healthy-appearing neoplastic cells were always abundant. These observations suggest the pre-treatment existence of autonomous cells that no conventional hormonal manipulation will succeed in destorying. However, the palliation that flutamide seems to afford makes it important to conduct an appropriately designed study that will compare it in a suitable fashion to the effectiveness of diethylstilbestrol.

Aged↗
PubMed1975

Chemotherapy of advanced prostatic carcinoma with cyclophosphamide or 5-fluorouracil: results of first national randomized study.

The National Prostatic Cancer Project has randomized this study for endocrine-resistant prostatic cancer patients for treatment with standard hormonal or other therapies compared to 5-fluorouracil and cyclophosphamide. Both agents were found at the probability level of 0.05 to have a significant advantage over standard treatment in terms of objective response, subjective improvement and minimal toxicity. Additional chemotherapy protocols are currently under way. This randomized trial is the first report of such a national study completed to date. We are much encouraged by this program and believe that additional agents now under consideration will provide additionally encouraging results.

Clinical Trials as Topic↗