Biomedical subjects

Timothy C Brand

Publications and source records attributed to Timothy C Brand.

7 recordsLinked to original sources

PubMed2006

Looking back at PCPT: looking forward to new paradigms in prostate cancer screening and prevention.

OBJECTIVES: Provide a critical summary of the latest interpretation of findings from the Prostate Cancer Prevention Trial (PCPT). METHODS: Findings from PCPT and recently published post-hoc analyses are reviewed. RESULTS: PCPT demonstrated that finasteride can reduce the prevalence of prostate cancer, permitted the first large-scale assessment of the performance characteristics of prostate-specific antigen for prostate cancer screening, and identified new-onset erectile dysfunction as an early predictor of cardiovascular events. CONCLUSIONS: PCPT has and will continue to yield valuable information regarding future strategies for prostate cancer prevention and detection, benign prostatic hyperplasia, and other matters of public health importance.

5-alpha Reductase Inhibitors↗

PubMed2006

Prostate cancer detection strategies.

Prostate cancer is the most common malignancy in men and, as a result, there has been a nationwide emphasis on screening and detection. With the widespread use of the prostate-specific antigen (PSA), prostate cancer screening effectively detects localized prostate cancer. However, recent reports have identified a significant proportion of prostate cancer in men with low PSA levels. Many of these cancers are higher-grade malignancies. Consequently, PSA may function more effectively as a screening tool when applied over a continuum that is associated with degree of risk, rather than a binary measure. Other markers are currently being investigated. Ideally, a marker will identify the malignancy that is a clinical threat, thereby avoiding intervention for indolent disease. Prevention strategies may be employed for higher-risk patients, and these strategies eventually may be tailored to genetic or other risks.

Genetic Markers↗

PubMed2006

Dealing with non-cancerous findings on prostate biopsy.

Most prostate biopsies do not show malignancy. The proper management of non-cancerous pathologic findings of the prostate is controversial. For this article, we reviewed the current literature for indications for repeat prostate biopsy after initial biopsies demonstrated non-cancerous prostatic tissue or benign prostatic hyperplasia. This review includes discussions of management of asymptomatic prostatitis and how it may affect prostate-specific antigen, and also the management of several potentially premalignant lesions such as atrophy, atypical small acinar proliferation, and high-grade prostatic intraepithelial neoplasia. There is a paucity of randomized trials in this area and, considering the high number of biopsies with non-malignant findings, we conclude that more investigation is warranted in this area.

Biopsy↗

PubMed2006

Chemoprevention of prostate cancer.

Prostate cancer is a common malignancy with multiple potential opportunities for cancer prevention. As the genetic basis of this malignancy is further understood, prevention strategies will be developed for individual patients based on specific risk factors and pathways of carcinogenesis. The PCPT has conclusively proven that prostate cancer prevention is possible. The results of the SELECT should be available within several years. An enormous challenge for the medical community will be the development of an efficient strategy to evaluate the substantial number of dietary, behavioral, and pharmacologic prevention opportunities. Ultimately, the goal of prostate can-cer prevention is to (1) identify men who are destined to develop clinically significant prostate cancer, and (2) provide individualized agents to prevent disease development.

Anticarcinogenic Agents↗

PubMed2006

Management of high risk metastatic prostate cancer: the case for novel therapies.

PURPOSE: We reviewed the results of preliminary studies of select novel agents for metastatic prostate cancer and discuss the potential benefit of these agents for earlier stage disease, eg biochemically recurrent prostate cancer with high risk features. MATERIALS AND METHODS: Available data on select investigational immunotherapies as well as endothelin-A receptor antagonists and survivin inhibitors were obtained and reviewed through PubMed searches, conference proceedings and unpublished proprietary information, when available. RESULTS: A large number of promising agents are in varying stages of development. Phase III results have been reported for the endothelin-A receptor antagonist atrasentan. Several immunotherapies are currently in phase II/III trials, namely the GM-CSF transduced tumor cell vaccine GVAX, the prostatic acid phosphatase loaded dendritic cell vaccine Provenge and the prostate specific antigen expressing poxvirus vaccine PROSTVAC-VF. Another immunotherapy, the prostate specific membrane antigen immunoconjugate MLN2704 (Millennium Pharmaceuticals, Cambridge, Massachusetts), is in phase I/II study. The first clinical inhibitors of survivin are in early phase I studies. Several of these agents, including atrasentan, have shown statistically significant but modest effects in the advanced disease setting in which they have been studied. CONCLUSIONS: Clinical trial design with these novel therapies presents particular challenges since most of these agents may induce disease stabilization rather than disease regression. There is a risk of false-negative results and failure to recognize a potentially efficacious agent if these cytostatic agents are studied only in men with advanced, heavily pretreated disease in whom life expectancy is measured in months. We advocate the early referral and enrollment of men with high risk prostate cancer in clinical trials.

Antineoplastic Agents↗

PubMed2006

Case report: Endoscopic laser lithotripsy of seminal-vesicle stones.

A 25-year-old man presented with painful ejaculation, an ejaculate volume of 0.75, and complaints of passing "granules" in the semen. Transrectal ultrasonography showed bilateral seminal vesicle enlargement. The patient underwent transurethral resection of the ejaculatory duct. The entry point of duct was resected using pure cutting current, resulting in the passage of multiple proteinaceous-appearing stones. Approximately 10 months later, the patient reported recurrent painful ejaculation and passage of granules in his semen. At cystoscopy, the ejaculatory duct openings were intubated with a cone-tipped catheter to perform bilateral seminal vesiculograms, which showed numerous mobile filling defects and a Steinstrasse appearance at the ejaculatory ducts. A 7F semirigid ureteroscope entered the lumen without difficulty over a guidewire, and the stones were fragmented with a 270-microm holmium laser fiber. The ejaculatory ducts were balloon dilated to 18F. To our knowledge, this is the first reported case where a ureteroscope was utilized to treat seminal-vesicle stones. The seminal vesiculogram proved to be extremely valuable in the diagnosis.

Adult↗

PubMed2006

Chemoprevention of prostate cancer with finasteride.

Prostate cancer is a significant cause of disease and death, making it an attractive target for chemoprevention. The association between lifetime exposure to dihydrotestosterone and risk of developing prostate cancer suggests that chemoprevention is possible with 5alpha-reductase inhibition. The recently completed Prostate Cancer Prevention Trial indicates that chemoprevention is possible with the 5alpha-reductase inhibitor finasteride. Development of a cost-effective chemoprevention strategy for prostate cancer is evolving, and is expected to have significant positive economic and public health benefits.

Animals↗