Obesity at Diagnosis and Prostate Cancer Prognosis and Recurrence Risk Following Primary Treatment by Radical Prostatectomy

The Association between Patient Characteristics and Biochemical Recurrence after Radical Prostatectomy

Background: Biochemical recurrence (BCR) represents the rise of prostate-specific antigen (PSA) levels after treatment with curative radical prostatectomy (RP) or radiation for prostate cancer. The objective of the current study was to test for the association between patient characteristics, namely age, body mass index (BMI), as well as prostate volume at surgery, and BCR after RP. Material and Methods: Within a tertiary care database, patients with prostate cancer treated with RP between January 2014 and June 2023 were included. Kaplan-Meier survival analyses and Cox regression models addressed BCR after RP according to patient characteristics. Results: Of 821 patients, the median age was 66 years (interquartile range [IQR] 61-71 years), BMI was 26.2 kg/m2 (IQR 24.3-28.8 kg/m2), and prostate volume was 40 cm3 (IQR 30-55 cm3). Median follow-up was 20 months. In survival analyses, the three-year BCR-free survival rates were 81 vs. 84 vs. 81% in patients aged ≤60 vs. 61-69 vs. 70 years (p = 0.1). In patients with BMI < 25.0 vs. 25.0-29.9 vs. ≥30.0 kg/m2, the three-year BCR-free survival rates were 84 vs. 81 vs. 84% (p = 0.7). In patients with prostate volume ≤40 vs. >40 cm3, the three-year BCR-free survival rates were 85 vs. 80% (p = 0.004). In multivariable Cox regression models accounting for patient and pathologic tumor characteristics and adjuvant radiation therapy, a higher prostate volume independently predicted BCR as continuous (hazard ratio 1.012, 95% confidence interval 1.005-1.019; p < 0.001), as well as categorized the variable based on the median (hazard ratio 1.66, 95% confidence interval 1.17-2.36; p = 0.005). Conversely, neither age nor BMI were significantly associated with BCR after RP. Conclusions: The higher prostate volume independently predicted BCR after RP, but not age or BMI at surgery. Consequently, patients with an elevated prostate volume should be considered for closer postoperative follow-up.

Comparative analysis of perioperative outcomes in obese patients undergoing robot-assisted radical prostatectomy (RARP) versus open radical prostatectomy (ORP): a systematic review and meta-analysis

The purpose of this study was to conduct a comparative analysis of the perioperative outcomes associated with robot-assisted laparoscopic prostatectomy (RARP) versus open radical prostatectomy (ORP) in the obese population diagnosed with prostate cancer. We performed a comprehensive search in key databases such as PubMed, Embase, Web of Science, and the Cochrane Library, encompassing studies of all languages, with a final search date of April 2024. We also omitted articles that consisted of conference abstracts and content that was not pertinent to our study. The aggregated outcomes were evaluated utilizing the metrics of weighted mean differences (WMDs) and odds ratios (ORs). A sensitivity analysis was also integrated into our assessment. The meta-analysis was facilitated by employing Stata/MP version 18 software. Additionally, the study was duly registered with PROSPERO under the identifier: CRD 42024540216. This meta-analysis, which included five trials, shows that compared to ORP, RARP is associated with a reduced estimated blood loss (EBL) (WMD -445.77, 95%CI -866.08, -25.45; p = 0.038), a decreased transfusion rate (OR 0.17, 95%CI 0.13, 0.21; p < 0.001), and a diminished overall complication rate (OR 0.71, 95%CI 0.58, 0.86; p = 0.001). No statistically significant differences were found in operative time (OT) (WMD 1.88, 95%CI -46.53, 50.28; p = 0.939) or length of stay (LOS) (WMD -0.41, 95%CI -1.07, 0.25; p = 0.221). Among patients with obesity and prostate cancer, RARP demonstrates advantages over ORP by reducing estimated blood loss, transfusion requirements, and the incidence of complications. Notably, there were no significant differences in operative duration and hospital stay between the two surgical approaches. These findings suggest that RARP could be a preferable surgical option for obese individuals with prostate cancer.

New Horizons: Epidemiology of Obesity, Diabetes Mellitus, and Cancer Prognosis

The global prevalence of obesity and diabetes mellitus has increased in parallel with increasing cancer incidence, due to environmental and lifestyle factors and population aging. Metabolic diseases are associated with increased cancer risk, so a growing number of patients with cancer have coexistent obesity and/or diabetes mellitus. In this narrative review, we highlight recent evidence on the clinical impact of obesity and diabetes mellitus on the prognosis of prostate, breast, and colorectal cancer, and provide an overview of the underlying mechanisms. There is evidence that obesity is associated with increased risk of recurrence, and all-cause and cancer-specific mortality among adults with prostate, breast, and colorectal cancer. Diabetes mellitus is associated with increased all-cause and cancer-specific mortality for these 3 cancers, beyond any impact of obesity. Evidence also suggests increased risk of colorectal cancer recurrence in patients with diabetes mellitus. The underlying mechanisms are multifactorial and likely include hormonal imbalances and chronic inflammation that promote cancer cell growth. Obesity and diabetes mellitus are associated with increased risk of complications and side effects of cancer treatment. Associated comorbidities such as impaired kidney function, cardiovascular disease, and neuropathies may preclude the use of guideline cancer treatment and are competing causes of death. Cancer patients with metabolic diseases require a designated clinical program and a multidisciplinary approach involving oncologists, endocrinologists, surgeons, nutritionists, and physiotherapists, to ensure coordinated and optimized patient care.

Tissue-Based Diagnostic Biomarkers of Aggressive Variant Prostate Cancer: A Narrative Review

Prostate cancer (PC) is a common malignancy among elderly men, characterized by great heterogeneity in its clinical course, ranging from an indolent to a highly aggressive disease. The aggressive variant of prostate cancer (AVPC) clinically shows an atypical pattern of disease progression, similar to that of small cell PC (SCPC), and also shares the chemo-responsiveness of SCPC. The term AVPC does not describe a specific histologic subtype of PC but rather the group of tumors that, irrespective of morphology, show an aggressive clinical course, dictated by androgen receptor (AR) indifference. AR indifference represents an adaptive response to androgen deprivation therapy (ADT), driven by epithelial plasticity, an inherent ability of tumor cells to adapt to their environment by changing their phenotypic characteristics in a bi-directional way. The molecular profile of AVPC entails combined alterations in the tumor suppressor genes retinoblastoma protein 1 (RB1), tumor protein 53 (TP53), and phosphatase and tensin homolog (PTEN). The understanding of the biologic heterogeneity of castration-resistant PC (CRPC) and the need to identify the subset of patients that would potentially benefit from specific therapies necessitate the development of prognostic and predictive biomarkers. This review aims to discuss the possible pathophysiologic mechanisms of AVPC development and the potential use of emerging tissue-based biomarkers in clinical practice.

Are associations between obesity and prostate cancer outcomes following radical prostatectomy the same in smokers and non-smokers? Results from the SEARCH Cohort

PURPOSE

Obesity and smoking have been associated with poor prostate cancer (PC) outcomes. We investigated associations between obesity and biochemical recurrence (BCR), metastasis, castrate resistant-PC (CRPC), PC-specific mortality (PCSM), and all-cause mortality (ACM) and examined if smoking modified these associations.

METHODS

We analyzed SEARCH Cohort data from men undergoing RP between 1990 and 2020. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between body mass index (BMI) as a continuous variable and weight status classifications (normal: 18.5 ≤ 25 kg/m2; overweight: 25-29.9 kg/m2; obese: ≥ 30 kg/m2) and PC outcomes.

RESULTS

Among 6,241 men, 1,326 (21%) were normal weight, 2,756 (44%) overweight and 2159 (35%) obese; 1,841 (30%) were never-smokers, 2,768 (44%) former and 1,632 (26%) current-smokers. Among all men, obesity was associated with non-significant increased risk of PCSM, adj-HR = 1.71; 0.98-2.98, P = 0.057, while overweight and obesity were inversely associated with ACM, adj-HR = 0.75; 0.66-0.84, P < 0.001 and adj-HR = 0.86; 0.75-0.99, P = 0.033, respectively. Other associations were null. BCR and ACM were stratified for smoking status given evidence for interactions (P = 0.048 and P = 0.054, respectively). Among current-smokers, overweight was associated with an increase in BCR (adj-HR = 1.30; 1.07-1.60, P = 0.011) and a decrease in ACM (adj-HR = 0.70; 0.58-0.84, P < 0.001). Among never-smokers, BMI (continuous) was associated with an increase in ACM (adj-HR = 1.03; 1.00-1.06, P = 0.033).

CONCLUSIONS

While our results are consistent with obesity as a risk factor for PCSM, we present evidence of effect modification by smoking for BCR and ACM highlighting the importance of stratifying by smoking status to better understand associations with body weight.

A holistic approach to prostate cancer treatment: natural products as enhancers to a medically minded approach

Prostate cancer (PC) has historically been the most diagnosed cancer in men. Though treatment for prostate cancer is often effective, it is also often very taxing on the body and commonly has negative quality of life implications. One such example is androgen suppression therapy (AST), which has severe side effects that can be mitigated through physical activity. Natural agents and protocols are increasingly studied for their merit against cancer and for their potential to treat cancer in ways that preserve the quality of life. Many agents and lifestyle choices have been shown to have success against prostate cancer. There is promising evidence that simple treatments such as green tea, pomegranate, and a regular exercise routine can be effective against prostate cancer. These treatments have the potential to enhance current treatment protocols. In this review, we will discuss the viability of many natural agents as treatments for prostate cancer and its complications.

Prediagnosis ultra-processed food consumption and prognosis of patients with colorectal, lung, prostate, or breast cancer: a large prospective multicenter study

Background and aims

Whether ultra-processed food consumption is associated with cancer prognosis remains unknown. We aimed to test whether prediagnosis ultra-processed food consumption is positively associated with all-cause and cancer-specific mortality in patients with colorectal, lung, prostate, or breast cancer.

Methods

This study included 1,100 colorectal cancer patients, 1750 lung cancer patients, 4,336 prostate cancer patients, and 2,443 breast cancer patients. Ultra-processed foods were assessed using the NOVA classification before the diagnosis of the first cancer. Multivariable Cox regression was used to calculate hazard ratio (HR) and 95% confidence interval (CI) for all-cause and cancer-specific mortality.

Results

High ultra-processed food consumption before cancer diagnosis was significantly associated with an increased risk of all-cause mortality in lung (HRquartile 4 vs. 1: 1.18; 95% CI: 0.98, 1.40; Ptrend = 0.021) and prostate (HRquartile 4 vs. 1: 1.18; 95% CI: 1.00, 1.39; Ptrend = 0.017) cancer patients in a nonlinear dose-response manner (all Pnonlinearity < 0.05), whereas no significant results were found for other associations of interest. Subgroup analyses additionally revealed a significantly positive association with colorectal cancer-specific mortality among colorectal cancer patients in stages I and II but not among those in stages III and IV (Pinteraction = 0.006), and with prostate cancer-specific mortality among prostate cancer patients with body mass index <25 but not among those with body mass index ≥25 (Pinteraction = 0.001).

Conclusion

Our study suggests that reducing ultra-processed food consumption before cancer diagnosis may improve the overall survival of patients with lung or prostate cancer, and the cancer-specific survival of certain subgroups of patients with colorectal or prostate cancer.

Post-diagnostic health behaviour scores and risk of prostate cancer progression and mortality

BACKGROUND

Individual behaviours are associated with prostate cancer (PC) progression. Behavioural scores, comprised of multiple risk factors, allow assessment of the combined impact of multiple behaviours.

METHODS

We examined the association between six a priori scores and risk of PC progression and mortality among 2156 men with PC in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) cohort: two scores developed based on the PC survivorship literature ('2021 Score [+ Diet]'); a score developed based on pre-diagnostic PC literature ('2015 Score'); and three scores based on US recommendations for cancer prevention ('WCRF/AICR Score') and survival ('ACS Score [+ Alcohol]'). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for progression and PC mortality via parametric survival models (interval censoring) and Cox models, respectively.

RESULTS

Over a median (IQR) of 6.4 (1.3, 13.7) years, we observed 192 progression and 73 PC mortality events. Higher (i.e., healthier) 2021 Score + Diet and WCRF/AICR Scores were inversely associated with risk of PC progression (2021 + Diet: HRcontinuous = 0.76, 95% CI: 0.63-0.90.

WCRF/AICR

HRcontinuous = 0.83, 95% CI: 0.67-1.02) and mortality (2021 + Diet: HRcontinuous = 0.65, 95% CI: 0.45-0.93.

WCRF/AICR

HRcontinuous = 0.71; 95% CI: 0.57-0.89). The ACS Score + Alcohol was only associated with progression (HRcontinuous = 0.89, 95% CI: 0.81-0.98) while the 2021 Score was only associated with PC mortality (HRcontinuous = 0.62, 95% CI: 0.45-0.85). The 2015 was not associated with PC progression or mortality.

CONCLUSION

Findings strengthen the evidence that behavioural modifications following a prostate cancer diagnosis may improve clinical outcomes.

Association between adiposity after diagnosis of prostate cancer and mortality: systematic review and meta-analysis

Objective

To explore the associations between adiposity indices, assessed at or after a diagnosis of prostate cancer, and mortality.

Design

Systematic review and meta-analysis.

Data sources

PubMed and Embase, from inception to 16 November 2022.

Eligibility criteria for selecting studies

Cohort studies or randomised controlled trials of men with a diagnosis of prostate cancer that investigated the associations between adiposity (body mass index, waist and hip circumference, waist-to-hip ratio, and subcutaneous and visceral adipose tissue) after diagnosis and mortality outcomes. A modified version of the risk of bias for nutrition observational studies tool was used to assess risk of bias.

Results

79 studies were identified that investigated adiposity indices after a diagnosis of prostate cancer in relation to mortality. No randomised controlled trials were found. A non-linear dose-response meta-analysis indicated a J shaped association between body mass index and all cause mortality (33 910 men, 11 095 deaths, 17 studies). The highest rate of all cause mortality was found at the lowest and upper range of the distribution: 11-23% higher rate for a body mass index of 17-21 and 4-43% higher rate for a body mass index of 30-40. The association between body mass index and mortality specific to prostate cancer was flat until body mass index reached 26-27, and then increased linearly by 8-66% for a body mass index of 30-40 (33 137 men, 2947 deaths, 13 studies), but the 95% confidence intervals were wide. These associations did not differ in most predefined subgroups by study design, number of deaths, anthropometric assessment, follow-up time, geographical location, prostate cancer risk group, and adjustment variables. No associations were found in meta-analyses between 10 cm increases in waist circumference and all cause mortality or mortality specific to prostate cancer, but only three studies were available. The few studies with data on change in weight, waist-to-hip ratio, and subcutaneous and visceral adipose tissue reported conflicting results.

Conclusions

This review suggests that patients with prostate cancer might benefit from maintaining a healthy weight and avoiding obesity. Future studies should investigate adiposity across different stages of cancer survivorship and use various parameters for distribution of adipose tissue.

Systematic review registration

Open Science Framework https://osf.io/qp3c4.

Protocol for a 4-arm randomized controlled trial testing remotely delivered exercise-only, diet-only, and exercise + diet interventions among men with prostate cancer treated with radical prostatectomy (Prostate 8-II)

BACKGROUND

Nutrition and physical activity are associated with prostate cancer recurrence and mortality. Few randomized controlled trials (RCT) have examined the effects of long-term exercise and diet changes on prostate cancer clinical, biological, and patient-reported outcomes.

METHODS

Prostate 8-II is a 4-arm RCT among 200 men with prostate cancer who chose radical prostatectomy (RP) as their primary treatment. Men are enrolled prior to RP and randomized to exercise-only, diet-only, exercise + diet, or usual care (50/arm). Participants begin their assigned intervention 0-5 weeks prior to RP and continue for 24-months following surgery. The 3 active intervention arms receive access to a web-portal and text messages, coaching calls, and other intervention resources (e.g., heart rate sensor and resistance bands and/or recipe booklet). Weekly exercise goals for the exercise intervention groups are 150 min moderate or 75 min vigorous aerobic exercise, 2 strength sessions, and 2 flexibility sessions. Diet intervention groups work with a dietitian to customize their goals (e.g., increase cruciferous vegetables, cooked tomatoes, healthy fats, fish; limit processed meats, whole milk). The primary endpoint is biochemical recurrence. Secondary endpoints include change in tumor biomarkers from biopsy to RP as well as patient-reported outcomes (e.g., quality-of-life), blood and urine biomarkers, and anthropometry at 0, 6, 12, and 24 months.

CONCLUSION

This 4-arm RCT will examine the impact of change in exercise and diet (alone or in combination) on prostate cancer recurrence, biology, and quality-of-life.

Post-diagnostic health behaviour scores in relation to fatal prostate cancer

BACKGROUND

Individual health behaviours have been associated with fatal prostate cancer (PCa). Their combined association with fatal PCa after diagnosis is unknown.

METHODS

This prospective cohort included 4518 men diagnosed with nonmetastatic PCa from the Health Professionals Follow-up Study. Exposures included a three-factor score integrating post-diagnostic fatal PCa risk factors ("2021 PCa Behaviour Score"), six-factor score integrating incident aggressive PCa risk factors ("2015 PCa Behaviour Score"), and two scores integrating recommendations for cancer prevention and survival, respectively. Multivariable Cox models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for fatal PCa.

RESULTS

Over a median 10.2 years, we observed 219 PCa deaths. Each additional point of one of the PCa-specific health behaviour scores (2015 PCa Behaviour Score) was associated with a 19% reduced fatal PCa risk (HR: 0.81, 95%CI: 0.68-0.97). The 2021 PCa Behaviour Score and scores integrating national recommendations were not associated with fatal PCa.

CONCLUSIONS

While a PCa-specific health behaviour score was associated with a reduced risk of fatal PCa, we did not otherwise observe strong evidence of associations between post-diagnostic scores and fatal PCa. Avoiding tobacco, healthy body size, and physical activity may decrease PCa death risk, but further research is needed to inform cancer survivorship recommendations.

Personalized Medicine for Prostate Cancer: Is Targeting Metabolism a Reality?

Prostate cancer invokes major shifts in gene transcription and metabolic signaling to mediate alterations in nutrient acquisition and metabolic substrate selection when compared to normal tissues. Exploiting such metabolic reprogramming is proposed to enable the development of targeted therapies for prostate cancer, yet there are several challenges to overcome before this becomes a reality. Herein, we outline the role of several nutrients known to contribute to prostate tumorigenesis, including fatty acids, glucose, lactate and glutamine, and discuss the major factors contributing to variability in prostate cancer metabolism, including cellular heterogeneity, genetic drivers and mutations, as well as complexity in the tumor microenvironment. The review draws from original studies employing immortalized prostate cancer cells, as well as more complex experimental models, including animals and humans, that more accurately reflect the complexity of the in vivo tumor microenvironment. In synthesizing this information, we consider the feasibility and potential limitations of implementing metabolic therapies for prostate cancer management.

Obesity and biochemical recurrence in clinically localised prostate cancer: a systematic review and meta-analysis of 86,490 patients

BACKGROUND

The association of obesity with biochemical recurrence (BCR) after treatment of clinically localised prostate cancer (PC) shows inconsistent results. Our aim was to systematically review all evidence evaluating obesity as a prognostic factor for BCR.

METHODS

We searched PubMed, Web of Science and Scopus, from inception to June 1, 2021. Cohort studies reporting BCR among PC patients stratified by body mass index (BMI) were included. To assess the quality of the selected studies, we used the Newcastle-Ottawa scale (NOS). Risk of BCR among obese patients (BMI ≥ 30 kg/m²) was compared with normal weight (BMI < 25), pooling individual hazard ratios (HR) in random-effect meta-analysis. Associations for continuous BMI per 5 kg/m² were also calculated. Subgroup analyses were conducted to assess reasons for heterogeneity and causal criteria were formally evaluated.

RESULTS

We identified 46 cohort studies including 86,490 PC patients. A total of 14,719 (17.1%) patients developed BCR. There was no consistent definition of BCR. Obesity was associated with BCR (HR: 1.25, 95% CI: 1.11-1.39, I²: 70.3%), and there was a 10% increase (95% CI: 4-15%, I²: 66.3%) in BCR per 5 kg/m² increase in BMI. The heterogeneity was high but decreased in the subgroup of highest-quality NOS score and when the BMI was measured by the researchers (I²: 0.0%). The association was consistent in patients receiving radical prostatectomy but not in patients receiving other therapies.

CONCLUSIONS

Obesity showed a moderate, consistent relationship with biochemical recurrence after radical prostatectomy. Measurement of BMI and BCR was variable, highlighting the need for standardised clinical guidelines. Preventive weight control programs may have a role in reducing BCR for clinically localised PC patients.

In1-Ghrelin Splicing Variant as a Key Element in the Pathophysiological Association Between Obesity and Prostate Cancer

CONTEXT

Recent studies emphasize the importance of considering the metabolic status to develop personalized medicine approaches. This is especially relevant in prostate cancer (PCa), wherein the diagnostic capability of prostate-specific antigen (PSA) dramatically drops when considering patients with PSA levels ranging from 3 to 10 ng/mL, the so-called grey zone. Hence, additional noninvasive diagnostic and/or prognostic PCa biomarkers are urgently needed, especially in the metabolic-status context.

OBJECTIVE

To assess the potential relation of urine In1-ghrelin (a ghrelin-splicing variant) levels with metabolic-related/pathological conditions (eg, obesity, diabetes, body mass index, insulin and glucose levels) and to define its potential clinical value in PCa (diagnostic/prognostic capacity) and relationship with PCa risk in patients with PSA in the grey zone.

METHODS

Urine In1-ghrelin levels were measured by radioimmunoassay in a clinically, metabolically, pathologically well-characterized cohort of patients without (n = 397) and with (n = 213) PCa with PSA in the grey zone.

RESULTS

Key obesity-related factors associated with PCa risk (BMI, diabetes, glucose and insulin levels) were strongly correlated to In1-ghrelin levels. Importantly, In1-ghrelin levels were higher in PCa patients compared to control patients with suspect of PCa but negative biopsy). Moreover, high In1-ghrelin levels were associated with increased PCa risk and linked to PCa aggressiveness (eg, tumor stage, lymphovascular invasion). In1-ghrelin levels added significant diagnostic value to a clinical model consisting of age, suspicious digital rectal exam, previous biopsy, and PSA levels. Furthermore, a multivariate model consisting of clinical and metabolic variables, including In1-ghrelin levels, showed high specificity and sensitivity to diagnose PCa (area under the receiver operating characteristic curve = 0.740).

CONCLUSIONS

Urine In1-ghrelin levels are associated with obesity-related factors and PCa risk and aggressiveness and could represent a novel and valuable noninvasive PCa biomarker, as well as a potential link in the pathophysiological relationship between obesity and PCa.

Prostate heterogeneity correlates with clinical features on multiparametric MRI

BACKGROUND

Prostate heterogeneity on multi-parametric MRI (mpMRI) may confound image interpretation by obscuring lesions; systematic biopsy may have a role in this context.

PURPOSE

To determine if prostate heterogeneity (1) correlates with clinical risk factors for prostate cancer and (2) associates with higher-grade tumor in systematic biopsy (SB), compared with MRI-directed target biopsy (MDTB), i.e., SB > MDTB, thus providing a rationale for combined biopsy.

METHODS

IRB-approved retrospective study included men who underwent mpMRI, SB, and MDTB between 2015 and 2017. Regions of interest were applied to the entire transition zone (TZ) and peripheral zone (PZ) on T2-weighted imaging (T2WI), apparent diffusion coefficient maps (ADC), and early dynamic contrast-enhanced (DCE) images on the midgland slice. Mean signal intensities and standard deviation (SD) of each zone were calculated. SD served as a measure of heterogeneity. Spearman's rank correlation analysis of clinical and imaging variables was performed. Univariate logistic regression was used to determine if any imaging variable associated with SB > MDTB.

RESULTS

93 patients were included. Significant correlations included age and TZ ADC heterogeneity (rho = 0.34, p = 0.013), PSA density, and mean TZ ADC (rho = - 0.29, p = 0.049). PZ T2WI heterogeneity correlated with PZ ADC heterogeneity (rho = 0.48, p < 0.001). PZ DCE heterogeneity correlated with TZ DCE heterogeneity (rho = 0.46, p < 0.001). TZ ADC heterogeneity was associated with SB > MDTB prior to multiple comparison correction (p = 0.032). p value after correction was 0.24.

CONCLUSION

TZ ADC heterogeneity correlated with age and may reflect prostatic hyperplasia and/or prostate cancer. PZ heterogeneity, possibly a measure of prostatitis, correlated with TZ hyperplasia and/or inflammation. TZ ADC heterogeneity was associated with SB > MDTB with p value of < 0.05 prior to multiple correction; future investigation is needed to further elucidate significance of ADC heterogeneity in prostate imaging.

Obesity as a Risk Factor for Prostate Cancer Mortality: A Systematic Review and Dose-Response Meta-Analysis of 280,199 Patients

Simple Summary

Results from individual studies on the association between obesity and prostate cancer mortality remain inconclusive; additionally, several large cohort studies have recently been conducted. We aimed to systematically review all available evidence and synthetize it using meta-analytic techniques. The results of our study showed that obesity was associated with prostate cancer specific mortality and all-cause mortality. The temporal association was consistent with a dose-response relationship. Our results demonstrated that obesity, a potentially modifiable prognostic factor, was associated with higher prostate cancer mortality. This study improved the evidence regarding the potential impact of lifestyle on improving prostate cancer prognosis. Strategies aimed at maintaining normal, or reducing abnormal, body mass index in diagnosed prostate cancer patients might improve survival. These results should guide urologists, oncologists, patients, policy-makers and primary care providers with respect to evidence-based practice and counselling concerning lifestyle changes after prostate cancer diagnosis.

Abstract

The aim of this study was to systematically review all evidence evaluating obesity as a prognostic factor for PC mortality. Cohort and case-control studies reporting mortality among PC patients stratified by body mass index (BMI) were included. The risk of mortality among obese patients (BMI ≥ 30) was compared with the risk for normal weight (BMI < 25) patients, pooling individual hazard ratios (HR) in random-effects meta-analyses. Reasons for heterogeneity were assessed in subgroup analyses. Dose-response associations for BMI per 5 kg/m² change were assessed. Among 7278 citations, 59 studies (280,199 patients) met inclusion criteria. Obesity was associated with increased PC-specific mortality (HR: 1.19, 95% CI: 1.10–1.28, I²: 44.4%) and all-cause mortality (HR: 1.09, 95% CI: 1.00–1.18, I²: 43.9%). There was a 9% increase (95% CI: 5–12%, I²: 39.4%) in PC-specific mortality and 3% increase (95% CI: 1–5%, I²: 24.3%) in all-cause mortality per 5 kg/m² increase in BMI. In analyses restricted to the higher quality subgroup (NOS ≥ 8), obesity was associated with increased PC-specific mortality (HR: 1.24, 95% CI: 1.14–1.35, I²: 0.0%) and maintained the dose-response relationship (HR: 1.11 per 5 kg/m² increase in BMI, 95% CI: 1.07–1.15, I²: 26.6%). Obesity had a moderate, consistent, temporal, and dose-response association with PC mortality. Weight control programs may have a role in improving PC survival.

Post-Diagnostic Dietary and Lifestyle Factors and Prostate Cancer Recurrence, Progression, and Mortality

PURPOSE OF REVIEW

This study aimed to summarize evidence published between 1999 and June 2020 examining diet and lifestyle after prostate cancer (PC) diagnosis in relation to risk of biochemical recurrence, PC progression, and PC-specific mortality.

RECENT FINDINGS

Secondary prevention is an important research area in cancer survivorship. A growing number of studies have reported associations between post-diagnostic modifiable behaviors and risk of PC outcomes. Evidence on modifiable lifestyle factors and PC remains limited. Where multiple studies exist, findings are often mixed. However, studies consistently suggest that smoking and consumption of whole milk/high-fat dairy are associated with higher risk of PC recurrence and mortality. In addition, physical activity and ½ to 1 glass of red wine/day have been associated with lower risk of recurrence and PC-specific mortality. Greater inclusion of racially/ethnically diverse groups in future research is necessary to understand these relationships in populations most impacted by adverse PC outcomes.

Dietary Factors and Prostate Cancer Development, Progression, and Reduction

Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer.

Postdiagnosis Body Mass Index, Weight Change, and Mortality From Prostate Cancer, Cardiovascular Disease, and All Causes Among Survivors of Nonmetastatic Prostate Cancer

PURPOSE

To investigate the association of postdiagnosis body mass index (BMI) and weight change with prostate cancer-specific mortality (PCSM), cardiovascular disease-related mortality (CVDM), and all-cause mortality among survivors of nonmetastatic prostate cancer.

METHODS

Men in the Cancer Prevention Study II Nutrition Cohort diagnosed with nonmetastatic prostate cancer between 1992 and 2013 were followed for mortality through December 2016. Current weight was self-reported on follow-up questionnaires approximately every 2 years. Postdiagnosis BMI was obtained from the first survey completed 1 to < 6 years after diagnosis. Weight change was the difference in weight between the first and second postdiagnosis surveys. Deaths occurring within 4 years of the follow-up were excluded to reduce bias from reverse causation. Analyses of BMI and weight change included 8,330 and 6,942 participants, respectively.

RESULTS

Postdiagnosis BMI analyses included 3,855 deaths from all causes (PCSM, n = 500; CVDM, n = 1,155). Using Cox proportional hazards models, hazard ratios (HRs) associated with postdiagnosis obesity (BMI ≥ 30 kg/m2) compared with healthy weight (BMI 18.5 to < 25.0 kg/m2) were 1.28 for PCSM (95% CI, 0.96 to 1.67), 1.24 for CVDM (95% CI, 1.03 to 1.49), and 1.23 for all-cause mortality (95% CI, 1.11 to 1.35). Weight gain analyses included 2,973 deaths (PCSM, n = 375; CVDM, n = 881). Postdiagnosis weight gain (> 5% of body weight), compared with stable weight (± < 3%), was associated with a higher risk of PCSM (HR, 1.65; 95% CI, 1.21 to 2.25) and all-cause mortality (HR, 1.27; 95% CI, 1.12 to 1.45) but not CVDM.

CONCLUSION

Results suggest that among survivors of nonmetastatic prostate cancer with largely localized disease, postdiagnosis obesity is associated with higher CVDM and all-cause mortality, and possibly higher PCSM, and that postdiagnosis weight gain may be associated with a higher mortality as a result of all causes and prostate cancer.