Research round up from the clinic - top four articles from July 2015:
1. Docetaxel in combination with Hormone Therapy for men with advanced prostate cancer
Earlier this month results from a phase 3 clinical trial, the CHAARTED trial, were published in the New England Journal of Medicine. The study, by Sweeney et al., involved almost 800 men diagnosed with hormone-sensitive metastatic (advanced) prostate cancer. The trial assessed whether providing hormone therapy plus docetaxel chemotherapy would result in longer overall survival than with hormone-therapy alone. The authors reported men with advanced prostate cancer were found to live up to 13.6 months longer with docetaxel in addition to hormone therapy. The investigators also did additional sub-analysis of those with high-volume disease (where prostate cancer had spread to four or more locations in the body). In this subgroup, men who were given docetaxel in combination with hormone therapy had an even greater improvement in survival, living 17 months longer than those given hormone therapy alone. The authors concluded that six cycles of docetaxel at the beginning of ADT for metastatic prostate cancer resulted in significantly longer overall survival than that with ADT alone. Prostate Cancer UK has some more information on the article here.
2. Neutrophil Count May Be Associated with Survival in Localized Prostate Cancer
Researchers in Montreal, Canada conducted a retrospective study of over 1,700 patients with localised prostate cancer treated with definitive external beam radiotherapy or brachytherapy. The study was designed to explore the influence of inflammatory markers on prostate cancer recurrence and survival after radiotherapy for patients with localised prostate cancer. The authors, Bahig et al., reported comorbidities other than cardiac history, and measurable peripheral plod markers, such as lymphocytes and neutrophil to lymphocyte ratio, were not associated with prostate cancer mortality. Conversely, neutrophil count, cardiac history, age, and Cancer of the Prostate Risk Assessment (CAPRA) score were associated with mortality. In addition, on multivariate analysis neutrophil count, age and Cancer of the Prostate Risk Assessment (CAPRA) score were also all independent predictors of overall survival. An association was not found for neutrophil count and biochemical recurrence free survival. In conclusion the authors stated neutrophil count, as a possible marker of systemic inflammation, appears to be an independent prognostic factor for overall mortality in localized prostate cancer. However, a validation cohort is needed to corroborate the results the group reported.
3. Lycopene intake and risk of prostate cancer – is there a relationship?
Chen et al., conducted a systematic review and meta-analysis looking at whether lycopene was inversely related to prostate cancer. They identified 26 studies (1999-2014), including over 17,000 cases of prostate cancer, which were analysed as part of the review. The review concluded lycopene could significantly reduce the incidence of prostate cancer with a linear dose-response effect for its intake, and nonlinear dose–response effect for circulating lycopene concentration. The authors also reported an inverse association between lycopene consumption and the risk of prostate cancer incidence for all studies, there was a trend for higher lycopene levels to reduce the incidence of prostate cancer. However, after removing one study in a sensitivity analysis and performing a sub-analysis from the remaining high-quality studies, higher lycopene consumption was shown to significantly lower prostate cancer risk. Limitations of the studies reviewed were also noted. Due to lycopene intake being assessed by food frequency questionnaires in different countries, and uses of different classifications of lycopene between studies, errors in measurement were inevitable.. In addition, the authors also noted not all studies adjusted for family history, which could impact the association between lycopene and prostate cancer risk. Furthermore, they also highlighted the need for further studies to determine the mechanism by which lycopene may act. Information from an analysis of global research on how diet, nutrition, physical activity and weight affect prostate cancer risk and survival from the World Cancer research Fund can be found here.
4. Adverse effects of common treatments for Benign Prostate Hyperplasia
A recent review by Traish et al., looked at data currently available and examined the potential role of 5α-reductase inhibitors (5α-RIs) therapy on the presence and persistence of adverse sexual side effects. Finasteride and Dutasteride are selective inhibitors of 5α-Rs, and are used as therapeutic agents for the treatment of lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH). They function by inhibiting the conversion of testosterone to 5α-dihydrotestosterone (5α-DHT) as well as several other critical steroid hormones. By reducing the concentration of 5α-DHT in the prostate, prostate volume decreases thus improving urinary flow. In this review the authors conclude that, in susceptible individuals, the use of finasteride and other 5α-R inhibitors is associated with a number of enduring sexual, mental and metabolic side effects, which can persist beyond the discontinuation of these therapies and profoundly compromise quality of life.