Does amount or type of alcohol influence the risk of prostate cancer?

BACKGROUND: Prostate cancer is one of the most common cancers among men, and it is unknown whether alcohol is associated with the development of prostate cancer. METHODS: The relationship between amount or type of alcohol and prostate cancer was studied in a pooled prospective setting conducted from 1976 to 1994 in Copenhagen, Denmark. The study population consisted of 12,989 subjects drawn from three different cohorts. During a mean follow-up of 12.3 yr, 233 subjects developed prostate cancer. RESULTS: None of the estimates for consumed amount of total alcohol diverged significantly from unity. Furthermore, drinkers of more than 13 beers, 13 glasses of wine, and 13 drinks of spirits had a risk of 1.03 (CI: 0.67, 1.60), 0.92 (CI: 0.42, 1.99), and 1.01 (CI: 0.52, 1.98), respectively, compared with abstainers of the given beverage of alcohol. CONCLUSION: These results suggest that neither amount nor type of alcohol is associated with the risk of prostate cancer.     

Effect of transforming growth factor beta (TGF-β) receptor I kinase inhibitor on prostate cancer bone growth

Transforming growth factor beta 1 (TGF-β1) has been implicated in the pathogenesis of prostate cancer (PCa) bone metastasis. In this study, we tested the antitumor efficacy of a selective TGF-β receptor I kinase inhibitor, LY2109761, in preclinical models. The effect of LY2109761 on the growth of MDA PCa 2b and PC-3 human PCa cells and primary mouse osteoblasts (PMOs) was assessed in vitro by measuring radiolabeled thymidine incorporation into DNA. In vivo, the right femurs of male SCID mice were injected with PCa cells. We monitored the tumor burden in control- and LY2109761-treated mice with MRI analysis and the PCa-induced bone response with X-ray and micro-CT analyses. Histologic changes in bone were studied by performing bone histomorphometric evaluations. PCa cells and PMOs expressed TGF-β receptor I. TGF-β1 induced pathway activation (as assessed by induced expression of p-Smad2) and inhibited cell growth in PC-3 cells and PMOs but not in MDA PCa 2b cells. LY2109761 had no effect on PCa cells but induced PMO proliferation in vitro. As expected, LY2109761 reversed the TGF-β1-induced pathway activation and growth inhibition in PC-3 cells and PMOs. In vivo, LY2109761 treatment for 6weeks resulted in increased volume in normal bone and increased osteoblast and osteoclast parameters. In addition, LY2109761 treatment significantly inhibited the growth of MDA PCa 2b and PC-3 in the bone of SCID mice (p<0.05); moreover, it resulted in significantly less bone loss and change in osteoclast-associated parameters in the PC-3 tumor-bearing bones than in the untreated mice. In summary, we report for the first time that targeting TGF-β receptors with LY2109761 can control PCa bone growth while increasing the mass of normal bone. This increased bone mass in nontumorous bone may be a desirable side effect of LY2109761 treatment for men with osteopenia or osteoporosis secondary to androgen-ablation therapy, reinforcing the benefit of effectively controlling PCa growth in bone. Thus, targeting TGF-β receptor I is a valuable intervention in men with advanced PCa.     

Alpha-linolenic acid and the risk of prostate cancer. What is the evidence?

PURPOSE: Several studies have examined the association between polyunsaturated fatty acids and prostate cancer risk. We evaluated the evidence on the association between the essential polyunsaturated fatty acid, known as alpha-linolenic acid, and the risk of prostate cancer in humans. MATERIALS AND METHODS: We comprehensively reviewed published studies on the association between alpha-linolenic acid and the risk of prostate cancer using MEDLINE. RESULTS: A number of studies have shown a positive association between dietary, plasma or red blood cell levels of alpha-linolenic acid and prostate cancer. Other studies have demonstrated either no association or a negative association. The limitations of these studies include the assumption that dietary or plasma alpha-linolenic acid levels are positively associated with prostate tissue alpha-linolenic acid levels, and measurement errors of dietary, plasma and red blood cell alpha-linolenic acid levels. CONCLUSIONS: More research is needed in this area before it can be concluded that there is an association between alpha-linolenic acid and prostate cancer.     

Does growth hormone treatment affect the risk of post-transplant renal cancer?

According to the analysis of the Collaborative Transplant Study (CTS), the incidence of renal carcinoma in patients with renal transplantation as well as with heart transplantation is significantly increased at any given patient age. The cumulative incidence 10 years after kidney transplantation is 185 per 100,000 patients in children below the age of 19 years at the time of transplantation. Age and immunosuppressive treatment seem to be the major risk factors. The majority of cancers develop within the native kidneys. Chronic transplant nephropathy and accelerated senescence may be further risk factors for the development of cancer within a kidney transplant. Growth hormone (GH) treatment could not be identified as an additional risk factor.     

What is the optimal management of high risk,clinically localized prostate cancer?

ObjectivesTo summarize the presentations and debate regarding the optimal treatment of localized high-risk prostate cancer as presented at the 2009 Spring Meeting of the Society of Urologic Oncology.Materials and methodsThe debate was centered on presentations arguing for radical prostatectomy (RP) or radiotherapy as the optimal treatment for this condition. The meeting presentations are summarized by their respective presenters herein.ResultsDr. James Eastham presents the varied definitions for “high-risk” prostate cancer as strongly influencing which patients end up in this cohort. Based upon this, between 3% and 38% of patients with high-risk features could be defined as “high-risk”. Despite that, these men do not have a uniformly poor prognosis after RP, and attention to surgical principles as outlined improve outcomes. Disease-specific survival at 12 years is excellent and up to one-half of these men may not need adjuvant or salvage therapies, depending on their specific disease characteristics. Adjuvant or salvage radiotherapies improve outcomes and are part of a sequential approach to treating these patients. Dr. Anthony Zietman presented radiotherapy as the gold-standard based upon large, randomized clinical trials of intermediate- and high-risk prostate cancer patients. Compared with androgen deprivation alone, the addition of radiotherapy provided a 12% cancer-specific survival advantage and 10% overall survival advantage. Dose escalation seems to confer further improvements in cancer control without significant escalation of toxicities, with more data forthcoming.ConclusionsThere are no randomized trials comparing RP to radiotherapy for any risk category. In high-risk prostate cancer patients, both approaches have potential benefits and cumulative toxicities that must be matched to disease characteristics and patient expectations in selecting a treatment course.     

Are prostate needle biopsies predictive of the laterality of significant cancer and positive surgical margins?

OBJECTIVE

To determine whether data obtained from preoperative prostate needle biopsy can predict the laterality of significant cancer and positive surgical margins on final‐specimen pathology after laparoscopic radical prostatectomy (LRP).

PATIENTS AND METHODS

Data from 490 patients undergoing LRP by one surgeon were reviewed retrospectively. The demographic characteristics, intraoperative data and pathological results were analysed. Univariate and multivariate analyses were used to determine which factors before and during LRP influenced the positive surgical margin status.

RESULTS

There was only minor agreement between the laterality of positive needle biopsies and laterality of any cancer and significant cancer on final‐specimen pathology (κ = 0.135 and 0.151, respectively). This was irrespective of the number of needle cores obtained or final‐specimen Gleason grade. Similarly, the laterality of dominant cancer on needle biopsy had only a minor agreement with the location of positive surgical margins (κ = 0.050) and fair agreement with the location of extracapsular extension on final‐specimen pathology (κ = 0.235).

CONCLUSIONS

Preoperative needle biopsy data have only a minor correlation with the laterality of significant cancer and positive surgical margins at final pathology of LRP specimens. Recognition of this fact, and the frequent bilaterality of significant cancer, with its potential for contralateral positive surgical margins even when the biopsies are positive only unilaterally, is an important consideration when planning nerve‐sparing, and potentially for focal therapy.     

Does physical activity reduce the risk of prostate cancer? A systematic review and meta-analysis

Context

Numerous observational epidemiologic studies have evaluated the association between physical activity and prostate cancer (PCa); however, the existing results are inconsistent.

Objective

To determine the association between physical activity and risk of PCa.

Evidence acquisition

A systematic search was performed using the Medline, Embase, and Web of Science databases through 15 May 2011 to identify all English-language articles that examined the effect of physical activity on the risk of PCa. This meta-analysis was conducted according to the guidelines for the meta-analysis of observational studies in epidemiology.

Evidence synthesis

This meta-analysis consisted of 88 294 cases from 19 eligible cohort studies and 24 eligible case-control studies. When data from both types of studies were combined, total physical activity (TPA) was significantly associated with a decreased risk of PCa (pooled relative risk [RR]: 0.90; 95% confidence interval [CI], 0.84-0.95). The pooled RR for occupational physical activity (OPA) and recreational physical activity (RPA) were 0.81 (95% CI, 0.73-0.91) and 0.95 (95% CI, 0.89-1.00), respectively. Notably, for TPA, we observed a significant PCa risk reduction for individuals between 20 and 45 yr of age (RR: 0.93; 95% CI, 0.89-0.97) and between 45 and 65 yr of age (RR: 0.91; 95% CI, 0.86-0.97) who performed activities but not for individuals <20 yr of age or >65 yr of age.

Conclusions

There appears to be an inverse association between physical activity and PCa risk, albeit a small one. Given that increasing physical activity has numerous other health benefits, men should be encouraged to increase their physical activity in both occupational and recreational time to improve their overall health and potentially decrease their risk of PCa.     

Testosterone replacement therapy and the risk of prostate cancer. Is there a link?

Substantial evidence supports the value of testosterone replacement therapy (TRT) in improving quality of life in men with proven aging male syndrome (AMS). Benefits of TRT include improved bone mineral density, reduced fracture risk, increased muscle mass, and improved mood, sense of well being, and libido, among others. There is currently a heated debate about the theoretical association between TRT and the initiation, progression, and aggressiveness of prostate cancer; however, this link has not been uniformly studied, and any results have been contradictory and nonconclusive. Although no clear evidence links TRT to prostate cancer, the possibility of increasing the risk of a clinical manifestation of a latent pre-existing malignancy can influence the decision about TRT use. Current recommendations are to exclude prostate cancer before initiating TRT in men over age 40 and to closely monitor men in the first year of testosterone replacement, followed by observation in subsequent years.