Prostate cancer evaluation

Prostate cancer evaluation/Effects on PSA Finasteride causes a decrease in serum PSA levels in patients with BPH even in the presence of prostate cancer. Consider this reduction when evaluating PSA laboratory data it does not suggest a beneficial effect of finasteride on prostate cancer. In controlled clinical trials, finasteride did not appear to alter the rate of prostate cancer detection. 

An evaluation of the Health Professionals Follow-Up Study (Giovannucci et al., 1995) has detected a lower prostate cancer risk associated with the greater consumption of tomatoes and related food products. Tomatoes are the primary dietary source of lycopene and lycopene concentrations are highest in testis and adrenal tissue (Clinton, 1998). In paired benign and malignant prostate tissue from 25 American men, 53-74 yrs, undergoing... 

Intervention trials confirmed this protective role of lycopene on prostate cancer risk. Three primary intervention studies evaluated the effect of lycopene supplementation on prostate cancer risk or on certain risk markers such as prostate-specific antigen (PSA) plasma concentration or oxidative alterations of leucocyte DNA. - All showed increases of plasma and prostate lycopene levels after diet supplementation with lycopene and inverse correlations between tumor incidence and risk biomarkers. 

Other dietary factors implicated in prostate cancer include retinol, carotenoids, lycopene, and vitamin D consumption.5,6 Retinol, or vitamin A, intake, especially in men older than age 70, is correlated with an increased risk of prostate cancer, whereas intake of its precursor, [3-carotene, has a protective or neutral effect. Lycopene, obtained primarily from tomatoes, decreases the risk of prostate cancer in small cohort studies. The antioxidant vitamin E also may decrease the risk of prostate cancer. Men who developed prostate cancer in one cohort study had lower levels of l,25(OH)2-vitamin D than matched controls, although a prospective study did not support this.2 Clearly, dietary risk factors require further evaluation, but because fat and vitamins are modifiable risk factors, dietary intervention may be promising in prostate cancer prevention. 

The common approach to prostate cancer screening today involves offering a baseline PSA and DRE at age 40, with annual evaluations beginning at age 50, to all men of normal risk with a 10-year or greater life expectancy. 

Ultrasensitive assays for PSA contribute to the earlier detection of prostate cancer relapse and (or) residual disease in prostatectomized patients as well as the more timely evaluation of response to current therapies. PSA determinations can be useful in detecting metastatic or persistent disease in patients following surgical or medical treatment of prostate cancer. Persistent elevation of PSA following treatment, or an increase in the pretreatment PSA concentrations, is indicative of recurrent or residual disease. Hence, PSA is widely accepted as an aid in the management of prostate cancer patients, and serum levels are most useful when sequential values are obtained and monitored over time. After complete removal of the prostate gland (radical prostatectomy), PSA levels should become very low or undetectable. A rise of the serum PSA level in prostatectomy patients indicates residual prostate tissue, recurrence, or metastasis of the disease (13, 16, 24, 36). 

Epidemiological and Human Dosimetry Studies. There are studies on the adverse effects of acrylonitrile in humans. These studies link acrylonitrile exposure and lung cancer. It has also been suggested that acrylonitrile may have the potential to cause prostate cancer. Many of the studies have major limitations including insufficient quantification of exposure, short follow-up, small study population, and inadequate evaluation of confounding associations. Additional studies would be useful in clarifying the cancer risk and estimating the exposure levels that lead to these effects. 

An important qualification must be made. While a biomarker may be of proven value in establishing whether a drug has the desired effect in patients or healthy volunteers (see Section 4.6.3) and for evaluation of the dose-response relationship, a biomarker may not be a surrogate for the clinical endpoint. Thus, suppression of testosterone after an initial rise will give an almost immediate endpoint for the effect of GnRH analogues in prostate cancer but the relationship breaks down later in the disease. Measures of blood glucose control are vital... 

In the bicalutamide prostate cancer programme, the adjuvant treatment of patients with advanced prostate carcinoma (T1-T4 NO/NX, MO) with bicalutamide (150 mg, once a day) was evaluated. 4052 patients were randomised to bicalutamide with best standard care (either radiation, prostatectomy or watchful waiting ), whereas 4061 patients received a placebo with best standard care. An initial reduction of prostate cancer recurrence, which was observed in an interim analysis, later was not confirmed [219]. As the survival time in the bicalutamide treatment group was decreased, the study was terminated ahead of time. 

T.R. DeGrado, R.E. Coleman, S. Wang, S.W. Baldwin, M.D. Orr, C.N. Robertson, T.J. Polascik, D.T. Price, Synthesis and evaluation of F-labeled choline as an oncologic tracer for positron emission tomography Initial findings in prostate cancer. Cancer Res. 61 (2001) 110-117. 

These NSAID MPC-7869 (R)-flurbiprofen) is a drug candidate (Phase III) for Alzheimer disease. It affects jS-amyloid deposition and metabolism and prevents cognitive deficits in transgenic animals. It is also being evaluated in hormone-naive prostate cancer (cf. infra). ... 

Schellhammer PF, Davis JW. An evaluation of bicalutamide in the treatment of prostate cancer, din Prost Cancer 2004 2 213-9. 

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