Phytonutrients and outcomes following breast cancer: a systematic review and meta-analysis of observational studies.

BACKGROUND: Phytonutrient intakes may improve outcomes following breast cancer, but the impact of postdiagnosis introduction vs established prediagnostic exposure as well as optimum doses has not been established. Evidence from observational studies for key exposures was evaluated, including dosage and intake time frames. METHODS: MEDLINE, EMBASE, CINAHL, Cochrane Library, ClinicalTrials.gov, and the ISRCTN registry were searched for prospective and retrospective observational studies investigating the impact of soybean, lignans, cruciferous (cabbage-family) vegetables, green tea, or their phytonutrients on breast cancer survival outcomes. A random-effects model was used to calculate summary hazard ratios (HRs) and 95% confidence intervals (CIs). Nonlinear dose-response analyses were conducted using restricted cubic splines. RESULTS: Thirty-two articles were included. Soy isoflavones were associated with a 26% reduced risk of recurrence (HR = 0.74, 95% CI = 0.60 to 0.92), particularly among postmenopausal (HR = 0.72, 95% CI = 0.55 to 0.94) and estrogen receptor-positive survivors (HR = 0.82, 95% CI = 0.70 to 0.97), with the greatest risk reduction at 60 mg/day. In mortality outcomes, the reduction was mostly at 20 to 40 mg/day. Soy protein and products were inversely associated with cancer-specific mortality for estrogen receptor-positive disease (HR = 0.75, 95% CI = 0.60 to 0.92). An inverse association was observed for serum or plasma enterolactone, measured prediagnosis and early postdiagnosis, with cancer-specific mortality (HR = 0.72, 95% CI = 0.58 to 0.90) and all-cause mortality (HR = 0.69, 95% CI = 0.57 to 0.83). No effects were observed for cruciferous vegetables. There was a 44% reduced risk of recurrence with prediagnostic green tea for stage I and II breast cancer (HR = 0.56, 95% CI = 0.38 to 0.83). CONCLUSIONS: Soy, enterolactone, and green tea demonstrated significant risk reductions in outcomes following breast cancer. Evidence is needed regarding the impact of postdiagnostic introduction or substantial increase of these exposures.

A Placebo-Controlled Double-Blinded Randomized Pilot Study of Combination Phytotherapy in Biochemically Recurrent Prostate Cancer.

BACKGROUND: Men with biochemical recurrence of prostate cancer following local therapies often use natural supplements in an attempt to delay metastases and/or avoid the need for more aggressive treatments with undesirable side-effects. While there is a growing body of research into phytotherapeutic agents in this cohort, with some promising results, as yet no definitive recommendations can be made. This pilot study was undertaken to assess the feasibility of a fully-powered study to examine the effects of this phytotherapeutic intervention (containing turmeric, resveratrol, green tea and broccoli sprouts) on PSA doubling time in men with biochemical recurrence with a moderate PSA rise rate. METHODS: A double blind, randomized, placebo-controlled parallel trial was conducted with 22 men with biochemically recurrent prostate cancer and a moderate rise rate (PSA doubling time of 4-15 months and no evidence of metastases from conventional imaging methods). Patients were randomized to either the active treatment arm or placebo for 12 weeks. The primary endpoints were feasibility of study recruitment and procedures, and measurement of proposed secondary endpoints (prostate symptoms, quality of life, anxiety, and depression as measured on the EORTC QLQ-C30 and PR-25, the IPSS and HADS). Data were collected to estimate PSA-log slopes and PSA-doubling times, using a mixed model, for both the pre-intervention and post-intervention periods. RESULTS: Adherence to study protocol was excellent, and the phytotherapeutic intervention was well-tolerated, with similar numbers of mild-to-moderate adverse events in the active and placebo arms. Both the intervention and data collection methods were acceptable to participants. No statistical difference between groups on clinical outcomes was expected in this pilot study. There was between-subject variation in the PSA post treatment, but on average the active treatment group experienced a non-significant increase in the log-slope of PSA (pre-treatment doubling time = 10.2 months, post-treatment doubling time = 5.5 months), and the placebo group experienced no change in the log-slope of PSA (pre-treatment doubling time = 10.8 months, post-treatment doubling time = 10.9 months). CONCLUSION: The findings suggest that a fully powered study of this combination is feasible in men with biochemically recurrent prostate cancer and a moderate PSA rise rate. Prostate 77:765-775, 2017. © 2017 Wiley Periodicals, Inc.

Soy and soy isoflavones in prostate cancer: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: To evaluate the evidence from randomized controlled trials (RCTs) on the efficacy and safety of soy/isoflavones in men with prostate cancer (PCa) or with a clinically identified risk of PCa. PATIENTS AND METHODS: MEDLINE, EMBASE, the Allied and Complementary Medicine (AMED), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) and the Cochrane Library databases were searched. We identified RCTs investigating soy/soy isoflavones as dietary supplements or dietary components for the secondary prevention or treatment of PCa in men with PCa or with a clinically identified risk of developing PCa. Studies of multi-component formulations were excluded. Six authors were contacted for further information for the meta-analyses. Methodological quality was assessed using the Cochrane Collaboration's risk-of- bias tool. The PRISMA statement for reporting systematic reviews was followed. RESULTS: Of the eight RCTs that met the inclusion criteria, six restricted recruitment to men diagnosed with PCa, while two included men with clinically identified risk of PCa. A large degree of heterogeneity was found with respect to dosages and preparations of soy/isoflavones administered. Most studies had small sample sizes and were of short duration. The risk of bias was assessed as low in all assessed studies except for one, for which the risk of bias was unclear. Meta-analyses of the two studies including men with identified risk of PCa found a significant reduction in PCa diagnosis after administration of soy/soy isoflavones (risk ratio = 0.49, 95% CI 0.26, 0.95). Meta-analyses indicated no significant differences between groups for prostate-specific antigen (PSA) levels or sex steroid endpoints (sex hormone-binding globulin [SHBG], testosterone, free testosterone, oestradiol and dihydrotestosterone). CONCLUSIONS: The results of a meta-analysis of two studies suggest there may be support for epidemiological findings of a potential role for soy/soy isoflavones in PCa risk reduction; however, a clear understanding of the impact of soy/isoflavones on PSA, total testosterone, free testosterone and SHBG levels in men with, or at identified risk of, PCa could not be derived from these data, given the limitations of sample size and study duration in individual trials. A good safety profile is shown by this meta-analysis for soy/soy isoflavones supplementation.

Vitex agnus-castus extracts for female reproductive disorders: a systematic review of clinical trials.

Vitex agnus-castus L. (chaste tree; chasteberry) is a popular herbal treatment, predominantly used for a range of female reproductive conditions in Anglo-American and European practice. The objective of this systematic review was to evaluate the evidence for the efficacy and safety of Vitex extracts from randomised, controlled trials investigating women's health.Eight databases were searched using Latin and common names for Vitex and phytotherapeutic preparations of the herb as a sole agent, together with filters for randomised, controlled trials or clinical trials. Methodological quality was assessed according to the Cochrane risk of bias and Jadad scales, as well as the proposed elaboration of CONSORT for reporting trials on herbal interventions.Thirteen randomised, controlled trials were identified and twelve are included in this review, of which eight investigated premenstrual syndrome, two premenstrual dysphoric disorder, and two latent hyperprolactinaemia. For premenstrual syndrome, seven of eight trials found Vitex extracts to be superior to placebo (5 of 6 studies), pyridoxine (1), and magnesium oxide (1). In premenstrual dysphoric disorder, one study reported Vitex to be equivalent to fluoxetine, while in the other, fluoxetine outperformed Vitex. In latent hyperprolactinaemia, one trial reported it to be superior to placebo for reducing TRH-stimulated prolactin secretion, normalising a shortened luteal phase, increasing mid-luteal progesterone and 17ß-oestradiol levels, while the other found Vitex comparable to bromocriptine for reducing serum prolactin levels and ameliorating cyclic mastalgia. Adverse events with Vitex were mild and generally infrequent. The methodological quality of the included studies varied, but was generally moderate-to-high. Limitations include small sample sizes in some studies, heterogeneity of conditions being treated, and a range of reference treatments.Despite some methodological limitations, the results from randomised, controlled trials to date suggest benefits for Vitex extracts in the treatment of premenstrual syndrome, premenstrual dysphoric disorder and latent hyperprolactinaemia. Further research is recommended, and greater transparency in reporting for future trials.

Are we drawing the right conclusions from randomised placebo-controlled trials? A post-hoc analysis of data from a randomised controlled trial.

BACKGROUND: Assumptions underlying placebo controlled trials include that the placebo effect impacts on all study arms equally, and that treatment effects are additional to the placebo effect. However, these assumptions have recently been challenged, and different mechanisms may potentially be operating in the placebo and treatment arms. The objective of the current study was to explore the nature of placebo versus pharmacological effects by comparing predictors of the placebo response with predictors of the treatment response in a randomised, placebo-controlled trial of a phytotherapeutic combination for the treatment of menopausal symptoms. A substantial placebo response was observed but no significant difference in efficacy between the two arms. METHODS: A post hoc analysis was conducted on data from 93 participants who completed this previously published study. Variables at baseline were investigated as potential predictors of the response on any of the endpoints of flushing, overall menopausal symptoms and depression. Focused tests were conducted using hierarchical linear regression analyses. Based on these findings, analyses were conducted for both groups separately. These findings are discussed in relation to existing literature on placebo effects. RESULTS: Distinct differences in predictors were observed between the placebo and active groups. A significant difference was found for study entry anxiety, and Greene Climacteric Scale (GCS) scores, on all three endpoints. Attitude to menopause was found to differ significantly between the two groups for GCS scores. Examination of the individual arms found anxiety at study entry to predict placebo response on all three outcome measures individually. In contrast, low anxiety was significantly associated with improvement in the active treatment group. None of the variables found to predict the placebo response was relevant to the treatment arm. CONCLUSION: This study was a post hoc analysis of predictors of the placebo versus treatment response. Whilst this study does not explore neurobiological mechanisms, these observations are consistent with the hypotheses that 'drug' effects and placebo effects are not necessarily additive, and that mutually exclusive mechanisms may be operating in the two arms. The need for more research in the area of mechanisms and mediators of placebo versus active responses is supported. TRIAL REGISTRATION: International Clinical Trials Registry ISRCTN98972974.

Hypericum perforatum with Vitex agnus-castus in menopausal symptoms: a randomized, controlled trial.

OBJECTIVE: To evaluate the effectiveness of a phytotherapeutic intervention comprising a combination of Hypericum perforatum (St. John's wort) and Vitex agnus-castus (Chaste tree/berry) in the management of menopausal symptoms. DESIGN: A double-blind, randomized, placebo-controlled, parallel trial was performed over 16 weeks in 100 eligible late-perimenopausal or postmenopausal women experiencing hot flushes and other menopausal symptoms. Herbal combination therapy or placebo tablets were administered twice daily. The primary endpoint was hot flush episodes. Secondary endpoints included Greene Climacteric Scale scores, Hamilton Depression Inventory scores, and Utian Quality of Life Scale scores. RESULTS: Ninety-three women completed the study. Data analysis on an intent-to-treat basis found no significant differences between the two groups for any of the endpoints. Analyses performed at interim data time points revealed no significant differences at week 4, 8, or 12 for daily weighted flushes or scores on the Greene Climacteric Scale or Hamilton Depression Inventory. However, significant improvements across the treatment phase were observed in both the placebo and active treatment groups for these endpoints. No significant change was found for either group on quality of life. CONCLUSION: The herbal combination of H. perforatum and V. agnus-castus was not found to be superior to placebo for the treatment of menopausal symptoms. The herbal combination was well tolerated with no significant adverse events noted in the short term. Robust findings from quality studies such as this are important for informing the community, healthcare providers, and regulatory authorities.