Dietary fatty acids have also been the subject of studies in the context of prostate cancer risk. Results have just been reported regarding these nutrients based on data collected in the Physician’s Health Study. While this study had as its primary goal the evaluation of aspirin and beta-carotene in the primary prevention of heart disease and cancer, the cohort provided the opportunity for case-control studies of other questions. One such study has just reported  which involved almost 15,000 apparently healthy men who provided blood samples in 1982. Blood fatty acid levels were measured for 476 men who developed prostate cancer during the 13-year follow-up and as well as for their matched controls. It was found that higher levels of the long-chain fatty acids mainly found in marine foods, and of linoleic acid, mainly found in non-hydrogenated vegetable oils, were associated with reduced risk of prostate cancer. In both, the relative risk reductions were about 40% when the highest quintile of serum level was compared to the lowest. The authors comment that in addition, their data suggest that the intake of polyunsaturated fatty acids appear unlikely to increase prostate cancer risk and that in addition, the intake of these fatty acids may in addition help prevent other common chronic diseases such as heart disease and diabetes. Thus these substances may have a broad implication in chronic disease prevention.
EARLY VS. DEFERRED HORMONAL TREATMENT OF LOCALLY ADVANCED PROSTATE CANCER
Localized prostate cancer generally implies organ-confined disease and the removal of the prostate or its irradiation generally results in a high probability of long-term freedom from recurrence. Locally advanced prostate generally implies that the tumor or tumors extent through the prostatic capsule or have invaded adjacent structures other than the seminal vesicles, and that distant (non-localized) metastasis is absent. Locally advanced disease can be difficult to clinically differentiate from metastatic disease. This is an important question since if the cancer is not localized, local treatment such as surgery or radiation therapy will not deal with the cancer cells or tumors outside the treatment area and while there may still be significant benefits, there is a high risk of recurrence. If it is localized but advanced, then the problem is for the treatment to deal with all locations of the cancer. In order to augment either radiation or surgery, hormone therapy is frequently used. Radiation therapy is the most commonly used treatment in conjunction with hormone therapy employed either before (neoadjuvant), concomitant or after (adjuvant) irradiation. The aim of adding hormone treatment is first to
reduce the risk of distant metastases by destroying micro-metastatic deposits at the time of diagnosis. addition, it reduces the risk of local recurrence, but the detailed mechanism is not clear.
One of nagging questions in this area is when to initiate hormone treatment, i.e. should it be early or deferred until standard care has failed. A recent meta-analysis of randomized clinical trials has addressed this issue . Of 108 trials identified, seven met the inclusion criteria and were of sufficient quality to merit use in the analysis. It was found that early intervention with hormone therapy significantly reduced all-cause mortality, cancer specific mortality, overall progression of the disease and both local and distant progression. Thus it was concluded that for patients with locally advanced prostate cancer, early intervention with hormones offered significant benefits when compared with delayed treatment.
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