An ongoing study is evaluating the potential benefits of a high-dose omega-3 supplementation for prostate cancer patients before and after radical prostatectomy.
Prostate cancer is the most common type of cancer in men. In Canada, 1 out of 8 men is expected to develop prostate cancer at some point in their lives and 1 in 27 will die from it. The probability of getting the disease increases with age and nearly 50% of men over the age of 50 years will have some degree of abnormalities in the cells of their prostates. The common treatment for men with an intermediate risk of prostate cancer is usually radiation therapy or radical prostatectomy (complete removal of prostate gland), which often comes with many side effects. For these patients, improvement in health and well-being can be achieved through dietary and lifestyle interventions.
Can a Dietary Supplement Benefit Those with Prostate Cancer?
Among some dietary interventions that have shown to be beneficial for cancer patients is supplementation with omega-3 fatty acids. Previous studies, however, have shown mixed results concerning whether omega-3 fatty acids, including those from seafood and fatty fish such aseicosapentaenoic acid (EPA) and docosahexanenoic acid (DHA), are associated with a decreased incidence of and slower progression of prostate cancer.
A Canadian study published in the BMC Cancer journal is currently investigating the potential effects of the administration of high doses of EPA before radical prostatectomy on three major outcomes: prostate cancer proliferation, inflammation, and quality of life. The study began in 2012, with the enrollment of the first patients, and scientists expect to end data collection in August, 2018. Their primary objective is to determine the effect of daily EPA supplementation compared to a placebo, on the proliferative index of prostate cancer cells.
Can Fish Oils Reduce Markers of Cancer?
This index is measured by the level of expression of nuclear Ki-67, a protein that is highly produced in the prostate during cancerous cell proliferation. Previous studies have showed that Ki-67 expression was highly reduced in individuals that had a low-fat diet enriched with fish oils. As secondary objectives, the authors aim to determine the effects of this supplementation on the levels of inflammatory mediators (molecules produced by the immune system) in the prostate and blood, and on psychosocial functioning and quality of life.
A total of 130 patients with moderate risk prostate cancer who are to undergo radical prostatectomy have been selected for the study. The researchers randomly divided the participants into two groups: 65 patients receiving pills with high doses of EPA (the intervention group), and 65 patients receiving placebo pills containing biologically neutral oils (the control group).All patients are required to take six pills a day starting six weeks before their surgery and continue taking the pills for one year after the surgery. The patients taking the EPA pills will be ingesting a total of 3mgof EPA daily. The patients will be assessed in the third, sixth, ninth, and twelfth month after the prostatectomy.
More specifically, the evaluation of Ki-67 protein levels will be conducted in the prostate tissue obtained from the surgery, while inflammation mediators will also be measured in the cancerous tissue, as well as in blood samples collected in the follow-up assessments. In a similar way, prostate-specific aspects of quality of life (urinary incontinence, urinary irritation/obstruction, bowel, vitality/hormonal, sexual function) will be assessed by scoring systems and clinical evaluation. The researchers will use validated questionnaires, rigorous scales and scoring systems to analyze anxiety and depression, fatigue, cognitive functions, cancer-specific anxiety, and wellbeing.
Results Will Benefit Prostate Cancer Patients
So far, studies that have investigated the influence of omega-3 supplementation in prostate cancer patients have generated inconclusive or conflicting results, bringing about the need for more comprehensive studies. This current study is the first one to examine the effects of preoperative omega-3 supplementation in the expression of Ki-67 protein in cancerous tissues, modulation of inflammatory response in the prostate tissue and blood, and quality of life among patients. If such dietary approach shows consistent results at the end of the study, prostate cancer patients will greatly benefit.
Written by Gustavo Caetano, B.Sc., M.Sc.
(1) Guertin M-H, Robitaille K, Pelletier J-F, Duchesne T, Julien P, Savard J, Bairati I, Fradet V. Effects of concentrated long-chain omega-3 polyunsaturated fatty acid supplementation before radical prostatectomy on prostate cancer proliferation, inflammation, and quality of life: study protocol for a phase IIb, randomized, double-blind, placebo controlled trial. BMC Cancer. 2018; 18-64.
(2) Nordqvist C. Prostate cancer in detail.(2017, November 27). Retrieved fromhttps://www.medicalnewstoday.com/articles/150086.php
(3) Omega-3 Fatty Acids:Fact Sheet for Health Professionals.(2016, November 2). Retrieved fromhttps://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/