General and abdominal obesity trajectories across adulthood,and risk of prostate cancer: results from the PROtEuS study,Montreal, Canada

Purpose

Greater body fatness is a probable cause of advanced prostate cancer (PCa). Body fat distribution and timing of exposure may be relevant. We investigated associations between body size trajectories and PCa incidence in a population-based case–control study in Montreal, Canada.

Methods

Cases (n?=?1,931), aged?≤?75 years, were diagnosed with PCa in 2005–2009; 1,994 controls were selected from the electoral list. Interviews were conducted to assess body mass index (BMI) and Stunkard’s silhouette at ages 20, 40, 50, 60 years, and before interview. Current waist and hip circumferences were measured, and a predictive model estimated waist circumference in the past. BMI and waist circumference trajectories were determined to identify subgroups. Logistic regression estimated odds ratios (OR) and 95% confidence intervals (CI) for the association between anthropometric indicators and PCa.

Results

Subjects with a current BMI?≥?30 kg/m² had a lower risk of overall PCa (OR 0.71, 95% CI 0.59–0.85). Associations with adult BMI followed similar trends for less and more aggressive tumors, with stronger inverse relationships in early adulthood. Contrastingly, current waist circumference?≥?102 cm was associated with elevated risk of high-grade PCa (OR 1.33, 95% CI 1.03–1.71). Men with increasing BMI or waist circumference adult trajectories had a lower risk of PCa, especially low-grade, than those in the normal-stable range. This was especially evident among men in the obese-increase group for BMI and waist circumference.

Conclusion

Abdominal obesity increased the risk of aggressive PCa. The inverse relationship between body size trajectories and PCa may reflect PSA hemodilution, lower detection, and/or a true etiological effect.

     

Diabetes mellitus and risk of prostate cancer in the health professionals follow‐up study

History of diabetes may be associated with decreased prostate cancer (PCa) risk. Published studies have not always accounted for time since diabetes diagnosis or confounding and effect modification by lifestyle factors. The authors investigated the relationship between diabetes and PCa risk in men in the Health Professionals Follow‐Up Study from 1986 to 2004. During that time, 4,511 new PCa cases were identified. Multivariate hazard ratios (HR) were estimated using Cox regression. The HR of PCa comparing men with vs. without diabetes was 0.83 and 95% confidence interval (CI): 0.74, 0.94. PCa risk was not reduced in the first year after diabetes diagnosis (HR: 1.30, CI: 0.97, 1.72), was lower for men diagnosed for 1–6 years (HR: 0.82, CI: 0.66, 1.02), and was even lower for men who had been diagnosed for 6–15 (HR: 0.75, CI: 0.61, 0.93) or >15 years (HR: 0.78, CI: 0.63, 0.96). Reduced PCa risk was stronger in men diagnosed before 1994 (pre‐PSA era) vs. after 1994. The authors also demonstrated that obese and diabetic men had a lower HR for PCa than those who were either not obese and diabetic or obese and non‐diabetic. Results are consistent with the hypothesis that diabetes is associated with reduced PCa risk. Potential biological mechanisms are discussed. © 2008 Wiley‐Liss, Inc.     

Prostate-specific antigen velocity and the detection of gleason score 7 to 10 prostate cancer

BACKGROUND: An increasing prostate-specific antigen (PSA) velocity is associated with a shorter survival after local therapy for prostate cancer. In this study, the authors evaluated whether PSA velocity was associated with prostate cancer detection and grade at diagnosis after adjusting for established predictors. METHODS: Between January 1989 and December 2003, 914 men who had PSA levels >/=4 ng/mL were identified by using the Center for Prostate Disease Research (CPDR) multicenter national database, including 541 men who were diagnosed with prostate cancer. Multivariable logistic regression analyses were performed that included continuous variables (PSA velocity and level, number of prior negative biopsies, and age) along with categorical variables (ethnicity and family history) were used to identify the factors associated with prostate cancer detection and grade. RESULTS: An increasing PSA velocity was associated with Gleason scores from 7 to 10 versus Gleason scores form 2 to 6 or no cancer (adjusted odds ratio [OR], 1.04 ng/mL per year; 95% confidence interval [95% CI], 1.003-1.085 ng/mL per year; P = .035). This finding was not evident in patients who had prostate cancers with Gleason scores between 2 and 6 or for any prostate cancer. PSA level was associated with the detection of any prostate cancer (OR, 1.06 ng/mL; 95% CI, 1.03-1.10 ng/mL; P = .004) and Gleason score 4 ng/mL. These findings, in conjunction with life expectancy, may be used when deciding which men should not be recommended for prostate biopsy despite a PSA level >4 ng/mL.     

Coffee consumption and risk of nonaggressive,aggressive and fatal prostate cancer—a dose–response meta-analysis

BackgroundExisting epidemiological evidence is controversial regarding the possible associations between coffee consumption and risk of prostate cancer (PCa) by aggressiveness of the disease.Materials and methodsWe conducted a random-effects dose–response meta-analysis to assess the relationships between coffee consumption and nonaggressive, aggressive and fatal PCa risk. Studies were identified by a search of Medline and Embase databases to 15 July 2013. We carried out separate analyses by grade (Gleason score: low-grade, high-grade) and stage (TNM staging system: localized, advanced) of the tumors. Nonaggressive tumors were defined as low-grade or localized, while aggressive tumors were defined as high-grade or advanced.ResultsEight studies (three case–control and five cohort) were included in this meta-analysis. Gleason 7 tumors were classified as high-grade in one study, while in another study, Gleason 7(4 + 3) tumors were classified as high-grade and Gleason 7(3 + 4) as low-grade. In the remaining four studies, Gleason 7 tumors were excluded from the analyses or analyzed separately. The pooled relative risk (RR) for a consumption increment of 3 cups/day was 0.97 [95% confidence interval (CI) 0.92–1.03] for low-grade PCa (n = 6), 0.97 (95% CI 0.94–0.99) for localized PCa (n = 6), 0.89 (95% CI 0.78–1.00) for high-grade PCa (n = 6), 0.95 (95% CI 0.85–1.06) for advanced PCa (n = 6) and 0.89 (95% CI 0.82–0.97) for fatal PCa (n = 4). No evidence of publication bias was observed. Heterogeneity was absent or marginal (I² range = 0–26%), with the only exception of the analysis on advanced PCa, where moderate heterogeneity was observed (I² = 60%). When restricting the analyses only to those studies that defined high-grade tumors as Gleason 8–10, the inverse association became slightly stronger [RR: 0.84 (95% CI 0.72–0.98); n = 4].ConclusionsResults from this dose–response meta-analysis suggest that coffee consumption may be inversely associated with the risk of fatal PCa. No clear evidence of an association with PCa incidence was observed.     

Coffee consumption and risk of localized,advanced and fatal prostate cancer: a population-based prospective study

BackgroundThe epidemiological evidence on possible relationships between coffee consumption and prostate cancer (PCa) risk by subtype of the disease (localized, advanced) and fatal PCa risk is limited.Materials and methodsA population-based cohort of 44 613 Swedish men aged 45–79 years was followed up from January 1998 through December 2010 for incidence of localized (n = 2368), advanced (n = 918) and fatal (n = 515) PCa. We assessed the associations between coffee consumption and localized, advanced and fatal PCa risk using competing-risk regressions. We examined possible effect modification by body mass index (BMI).ResultsFor localized PCa, each one cup increase in daily coffee consumption was associated with a 3% reduced risk [sub-hazard ratio (SHR) = 0.97, 95% confidence interval (CI) = 0.95–0.99]. For advanced and fatal PCa, we found a non-significant inverse association; each one cup increase was associated with a 2% reduced risk of advanced [SHR (95% CI) = 0.98 (0.95–1.02)] and fatal PCa [SHR (95% CI) = 0.98 (0.93–1.03)]. We observed evidence of effect modification by BMI for localized PCa (P_interaction = 0.03); the inverse association was stronger among overweight and obese men (BMI ≥ 25 kg/m²) compared with normal-weight men (BMI < 25 kg/m²).ConclusionsWe observed a clear inverse association between coffee consumption and risk of localized PCa, especially among overweight and obese men.     

Improved prognosis in gastric adenocarcinoma among metformin users in a population-based study

Background Metformin may improve the prognosis in gastric adenocarcinoma, but the existing literature is limited and contradictory.Methods This was a Swedish population-based cohort study of diabetes patients who were diagnosed with gastric adenocarcinoma in 2005–2018 and followed up until December 2019. The data were retrieved from four national health data registries: Prescribed Drug Registry, Cancer Registry, Patient Registry and Cause of Death Registry. Associations between metformin use before the gastric adenocarcinoma diagnosis and the risk of disease-specific and all-cause mortality were assessed using multivariable Cox proportional hazard regression. The hazard ratios (HRs) and 95% confidence intervals (CIs) were adjusted for sex, age, calendar year, comorbidity, use of non-steroidal anti-inflammatory drugs or aspirin, and use of statins.Results Compared with non-users, metformin users had a decreased risk of disease-specific mortality (HR 0.79, 95% CI 0.67–0.93) and all-cause mortality (HR 0.78, 95% CI 0.68–0.90). The associations were seemingly stronger among patients of female sex (HR 0.66, 95% CI 0.49–0.89), patients with tumour stage III or IV (HR 0.71, 95% CI 0.58–0.88), and those with the least comorbidity (HR 0.71, 95% CI 0.57–0.89).Conclusions Metformin use may improve survival in gastric adenocarcinoma among diabetes patients.Subject terms: Gastric cancer, Epidemiology, Cancer epidemiology     

Influence of age on predictiveness of genetic risk score for prostate cancer in a Chinese hospital-based biopsy cohort

Background

We investigated whether age influences the predictiveness of genetic risk score (GRS) for prostate cancer (PCa) in a Chinese hospital-based biopsy cohort.

Methods

We included consecutive patients who underwent prostate biopsies in two tertiary centers between 2012 and 2014. GRS was calculated using 24 PCa-associated genetic variants and its predictiveness was assessed by area under curve (AUC).

Results

Of 1120 men tested, 724 with prostate-specific antigen (PSA) < 20 ng/ml were selected for further analysis. Patients were divided into 3 groups by age cutoffs at 60 and 70 years. GRS significantly predicted PCa for all patients (AUC: 0.561; 95% CI: 0.514–0.609) and was an independent predictor in multivariate analysis for the 60–70 year-olds (AUC: 0.612, 95% CI: 0.541–0.684), but not for patients aged < 60 years or ≥70 years. For PCa with Gleason score ≥7, GRS discriminative ability was 0.582 (95% CI=0.527–0.637) for all patients, and 0.647 (95% CI: 0.541–0.684) for the 60–70 year-old group.

Conclusion

GRS significantly increased clinical prediction of PCa and high-grade disease in Chinese men aged 60–70 years, which implies that men in this age group would benefit most from genetic testing.     

Lifestyle and Prostate Cancer Among Older African-American and Caucasian Men in South Carolina

OBJECTIVE: We investigated the association between lifestyle and prostate cancer risk among Caucasian and African-American men, separately. METHODS: This population-based case-control study of prostate cancer among men aged 65-79 years was conducted between 2000 and 2002 in South Carolina. Telephone interviews were completed with 416 incident prostate cancer cases ascertained through the South Carolina Central Cancer Registry, and 429 controls identified through the Health Care Financing Administration Medicare beneficiary file (with respective response rates of 71% and 64%). RESULTS: Caucasian men working in production, transportation, and material moving had increased prostate cancer risk (odds ratio [OR] = 2.04, 95% confidence interval [CI] 1.17-3.54), while African-American men in the military had reduced prostate cancer risk (OR = 0.19, 95% CI 0.05-0.76). Having five or more prostate specific antigen (PSA) tests within the past five years was associated with prostate cancer among Caucasian men; however, African-American men with prostate cancer tended to have fewer PSA tests. Increasing lycopene consumption was associated with a reduced risk of prostate cancer among Caucasian men (p = 0.03), but not among African-American men. CONCLUSIONS: In this population-based case-control study conducted in South Carolina we did not find marked differences in lifestyle factors associated with prostate cancer by race.     

Diagnostic characteristics of lethal prostate cancer

BackgroundThe diagnostic characteristics of men who eventually die from prostate cancer (PCa) and the extent to which early diagnostic strategies have affected these characteristics are unclear. We aimed to investigate trends in survival and clinical presentation at diagnosis in men who eventually died from PCa.Patients and methodsBased on the national database, the Danish Prostate Cancer Registry, a nationwide population-based study of all 19,487 men who died from PCa in Denmark between 1995 and 2013 was conducted. Trends in median survival and trends in age, prostate-specific antigen (PSA), clinical stage, and Gleason score (GS) at diagnosis were analysed.ResultsA total of 46.9%, 16.8%, and 36.3% had metastatic (M+), locally advanced/lymph node positive (LaN+), and localised disease, respectively, at diagnosis. Only 0.15% had localised disease, GS ≤ 6 and PSA<10. Over time, the proportion of men with M+ disease at diagnosis decreased from 54.0–38.3% (p < 0.0001), whereas the proportion LaN + disease increased from 8.6–27.3% (p < 0.0001). The proportion of localised disease remained stable at 33.2–41.9%. Median survival increased 2.11 years from 1.88 (95% CI: 1.68–2.08) in 1995 to 3.99 (95% CI: 3.71–4.28) years in 2013, p < 0.0001.ConclusionsIn a large population-based study, the results confirmed concurrent literature that the majority of men who eventually died from PCa had LaN+ or M+ disease at diagnosis. The proportion of men with M+ disease at diagnosis decreased significantly over time, parallelled by an increase in median survival. Taken together, this indicates a lead-time effect on survival, which presently, however, is not substantial enough to result in a reduced PCa-specific mortality.     

Serum inflammatory markers in relation to prostate cancer severity and death in the Swedish AMORIS study

Inflammation is a well‐documented driver of cancer development and progression. However, little is known about its role in prostate carcinogenesis. Thus, we examined the association of C‐reactive protein (CRP), haptoglobin, albumin and white blood cells (WBC) with prostate cancer (PCa) severity (defined by PCa risk category and clinicopathological characteristics) and progression (defined by PCa death). We selected 8,471 Swedish men with newly diagnosed PCa who had exposure measurements taken approximately 14 years prior to diagnosis. We calculated odds ratio (OR) and 95% confidence interval (CI) for the associations between the inflammatory markers and PCa severity using logistic regression, while Cox proportional hazard regression was used for the associations with overall and PCa death. Serum CRP levels were associated with increased odds of high risk and metastatic PCa, and high PSA levels (≥20 µg/L) (OR: 1.29; 95% CI: 1.06–1.56, 1.32; 1.05–1.65 and 1.51; 1.26–1.81, respectively). Similarly, higher haptoglobin levels were associated with increased odds of metastatic PCa, high PSA level and possibly high grade PCa (1.38; 1.10–1.74, 1.50; 1.17–1.93 and 1.25; 1.00–1.56, respectively). Albumin was positively associated with Gleason 4 + 3 tumour (1.38; 1.02–1.86) and overall death (HR_{unit increase in log}: 1.60; 95% CI: 1.11–2.30), but inversely associated with high risk PCa and high PSA levels (≥20 µg/L) (0.71; 0.56–0.89 and 0.72; 0.5 9–0.90). WBC was associated with increased odds of T3–T4 PCa. Except for albumin, none of these markers were associated with PCa death or overall death. Systemic inflammation as early as 14 years prior to diagnosis may influence prostate cancer severity.     

Prostate cancer incidence in men with prostate-specific antigen below 3 ng/mL: The Finnish Randomized Study of Screening for Prostate Cancer

Prostate-specific antigen (PSA)-based screening for prostate cancer (PCa) can reduce PCa mortality, but also involves overdetection of low-risk disease with potential adverse effects. We evaluated PCa incidence among men with PSA below 3 ng/mL and no PCa diagnosis at the first screening round of the Finnish Randomized Study of Screening for PCa. Follow-up started at the first screening attendance and ended at PCa diagnosis, emigration, death or the common closing date (December 2016), whichever came first. Cox regression analysis was used to estimate hazard ratios and their confidence intervals (CI). Among men with PSA <3 ng/mL, cumulative PCa incidence was 9.1% after 17.6 years median follow-up. Cumulative incidence was 3.6% among men with baseline PSA 0 to 0.99 ng/mL, 11.5% in those with PSA 1.0 to 1.99 ng/mL and 25.7% among men with PSA 2 to 2.99 ng/mL (hazard ratio 9.0, 95% CI: 7.9-10.2 for the latter). The differences by PSA level were most striking for low-risk disease based on Gleason score and EAU risk group. PSA values <1 ng/mL indicate a very low 20-year risk, while at PSA 2 to 2.99 ng/mL risks are materially higher, with 4- to 5-fold risk for aggressive disease. Using risk-stratification and appropriate rescreening intervals will reduce screening intensity and overdetection. Using cumulative incidence of clinically significant PCa (csPCa) as the criterion, rescreening intervals could range from approximately 3 years for men with initial PSA 2 to 2.99 ng/mL, 6 years for men with PSA 1 to 1.99 ng/mL to 10 years for men with PSA <1 ng/mL.     

Do prostate cancer risk models improve the predictive accuracy of PSA screening? A meta-analysis

Despite the extensive development of prostate cancer (PCa) risk models that are used for patient–clinician decision-making for PCa screening, their predictive accuracy is unknown. In a meta-analysis of six different risk prediction models, results show that models have the potential to increase the sensitivity of PSA screening to detect any PCa (44% versus 21%).BackgroundDespite the extensive development of risk prediction models to aid patient decision-making on prostate screening, it is unknown whether these models could improve predictive accuracy of PSA testing to detect prostate cancer (PCa). The objective of this study was to perform a systematic review to identify PCa risk models and to assess the model's performance to predict PCa by conducting a meta-analysis.DesignA systematic literature search of Medline was conducted to identify PCa predictive risk models that used at least two variables, of which one of the variables was prostate-specific antigen (PSA) level. Model performance (discrimination and calibration) was assessed. Prediction models validated in ≥5 study populations and reported area under the curve (AUC) for prediction of any or clinically significant PCa were eligible for meta-analysis. Summary AUC and 95% CIs were calculated using a random-effects model.ResultsThe systematic review identified 127 unique PCa prediction models; however, only six models met study criteria for meta-analysis for predicting any PCa: Prostataclass, Finne, Karakiewcz Prostate Cancer Prevention Trial (PCPT), Chun, and the European Randomized Study of Screening for Prostate Cancer Risk Calculator 3 (ERSPC RC3). Summary AUC estimates show that PCPT does not differ from PSA testing (0.66) despite performing better in studies validating both PSA and PCPT. Predictive accuracy to discriminate PCa increases with Finne (AUC = 0.74), Karakiewcz (AUC = 0.74), Chun (AUC = 0.76) and ERSPC RC3 and Prostataclass have the highest discriminative value (AUC = 0.79), which is equivalent to doubling the sensitivity of PSA testing (44% versus 21%) without loss of specificity. The discriminative accuracy of PCPT to detect clinically significant PCa was AUC = 0.71. Calibration measures of the models were poorly reported.ConclusionsRisk prediction models improve the predictive accuracy of PSA testing to detect PCa. Future developments in the use of PCa risk models should evaluate its clinical effectiveness in practice.     

Metformin use and prostate cancer in Caucasian men: results from a population-based case–control study

Purpose  

Metformin is a commonly used medication for type II diabetes mellitus. Epidemiologic studies have suggested a decreased relative risk of cancer with metformin use, and preclinical studies of prostate cancer (PCa) have shown antitumor activity with metformin. In this study, we explore the relationship between metformin use and PCa risk in a population-based case–control study.     

Long-term aspirin use and the risk of total, high-grade, regionally advanced and lethal prostate cancer in a prospective cohort of health professionals, 1988-2006

Experimental studies suggest a role for aspirin in the chemoprevention of prostate cancer and epidemiological evidence supports a modest inverse association between regular aspirin use and prostate cancer risk, especially for advanced disease. In a prospective cohort study of 51,529 health professionals aged 40-75 years at baseline, we evaluated long-term aspirin use and the incidence of total, high-grade (Gleason 8-10, n = 488), regionally advanced (T3b-T4 or N1, n = 228) and lethal prostate cancer (M1, bony metastases or prostate cancer death, n = 580) from 1988-2006. We used Cox proportional hazards regression to evaluate risk associated with frequency (days/week), quantity (tablets/week), recency and duration of aspirin use after multivariable adjustment for confounders and other predictors of prostate cancer risk. A total of 4,858 men were diagnosed with prostate cancer during the 18-year study period. Men taking ≥ 2 adult-strength aspirin tablets a week had a 10% lower risk of prostate cancer (p-for-trend = 0.02). For regionally advanced cancer, we observed no significant associations with aspirin use. For high-grade and lethal disease, men taking ≥ 6 adult-strength tablets/week experienced similar reductions in risk hazard ratio [HR = 0.72 (95% confidence intervals [CI]: 0.54, 0.96) and HR = 0.71 (95% CI: 0.50, 1.00)]. Analytical approaches to address bias from more frequent prostate-specific antigen screening among aspirin users did not yield different conclusions. We observed reductions in the risk of high-grade and lethal prostate cancer associated with higher doses of aspirin, but not with greater frequency or duration, in a large, prospective cohort of health professionals. Our data support earlier observations of modest inverse associations with advanced prostate cancer.     

Active Surveillance Versus Radical Prostatectomy in Favorable-risk Localized Prostate Cancer

BackgroundActive surveillance (AS) and radical prostatectomy (RP) are both accepted treatments for men with favorable-risk localized prostate cancer (PCa) (ie, clinical tumor category 1-2b, Gleason Grade Group 1-2, and prostate-specific antigen < 20 ng/mL). However, head-to-head studies comparing oncologic outcomes and survival between these 2 treatment strategies are warranted. The objective of this study was to compare the use of prostate cancer treatments and PCa death in men managed on AS and men who underwent immediate RP.Patients and MethodsThis was an observational study including 647 men on AS and 647 men treated with RP propensity score matched. We examined the 10-year cumulative incidence of salvage radiotherapy, hormonal therapy, castration-resistant PCa, and PCa death.ResultsThe 10-year curative treatment-free survival for men on AS was 61% (95% confidence interval [CI], 57%-65%). No differences in use of salvage radiotherapy (AS, 2.7%; 95% CI, 1.4%-4.1% vs. RP 5.4%; 95% CI, 3.4%-7.3%), hormonal therapy (AS, 6.9%; 95% CI, 4.4%-9.4% vs. RP, 4.1%; 95% CI, 2.5%-5.6%), developing castration-resistant PCa (AS, 1.7%; 95% CI, 0.5%-2.9% vs. RP, 2.0%; 95% CI, 0.7%-3.4%), or cumulative PCa mortality (AS, 0.4%; 95% CI, 0%-1.0% vs. RP, 0.5%; 95% CI, 0%-1.5%) were observed between the treatment strategies. The main limitation was the non-random allocation to treatment strategy.ConclusionIn this observational study on men with favorable-risk localized PCa, we found similar PCa mortality at 10 years between men on AS and men who underwent immediate RP. Moreover, there were no differences in the use of PCa therapies between the groups. Our study supports active surveillance as a treatment strategy for men with favorable-risk localized PCa.     

Real-world use of enzalutamide in men with nonmetastatic castration-resistant prostate cancer in Japan

Background

The purpose of the study is to evaluate real-world effectiveness and safety of enzalutamide in men with nonmetastatic castration-resistant prostate cancer (nmCRPC) in Japan.

Methods

This was a retrospective evaluation of medical records from men in Japan who started enzalutamide treatment from November 1, 2014, to March 31, 2018, and received androgen deprivation therapy throughout. The primary endpoint was time to prostate-specific antigen (PSA) progression. Secondary endpoints included PSA response rate, time to first use of new antineoplastic therapy, time to first use of cytotoxic chemotherapy, and enzalutamide treatment duration. An exploratory analysis of metastasis-free survival (MFS) was also performed. Adverse events (AEs) were analyzed to assess safety.

Results

Based on data from medical records of 205 men in Japan, median time to PSA progression was 27 months (95% confidence interval [CI] 19–not reached [NR]), with 82.5% and 52.0% of men achieving PSA response rates of ≥ 50% and ≥ 90%, respectively. Median time to first use of new antineoplastic therapy was 36 months (95% CI 27−NR) and median enzalutamide treatment duration was 13 months (interquartile range: 7–24). Median time to first use of cytotoxic chemotherapy was NR (95% CI 41−NR). Median MFS was 29 months (95% CI 23−35). In total, 51.7% of men experienced AEs, with malaise (18.5%), decreased appetite (10.7%), and nausea (4.9%) the most frequently reported.

Conclusions

This is the first study to demonstrate the real-world effectiveness and safety of enzalutamide in men with nmCRPC in Japan, further informing healthcare providers about available treatment options for this patient population.

     

Risk of suicide in men with low-risk prostate cancer

PurposeRisk of suicide is increased among men with prostate cancer. We investigated this association among men with low-risk cancer, usually detected by prostate specific antigen (PSA)-testing.Patients and MethodsRelative risk (RR) of suicide was calculated by use of Poisson regression analysis within the Prostate Cancer data Base Sweden (PCBaSe) 2.0, a nation-wide, population-based database, comparing 105,736 men diagnosed with prostate cancer between 1997–2009 to 528,658 matched prostate cancer-free men.ResultsDuring the first 6 months after diagnosis, there were 38 suicides among men with prostate cancer; incidence rate 0.73 per 1000 person-years (PY) and 30 suicides in the comparison cohort; 0.11 per 1000 PY, corresponding to a RR of suicide of 6.5 (95% confidence interval (CI) 4.0–10). Risk was highest among men with distant metastases, incidence rate 1.25 per 1000 PY, RR 10 (95% CI 5.1–21) but risk was also increased for men with low-risk tumours, incidence rate difference 0.45 per 1000 PY and RR 5.2 (95% CI 2.3–12) and across categories of socioeconomic status and comorbidity. Eighteen months after diagnosis, risk of suicide had decreased to 0.27 per 1000 PY, RR 1.0 (95% CI 0.68–1.5) for low-risk prostate cancer but remained increased among men with metastases, 0.57 per 1000 PY, RR 1.8 (95% CI 1.1–2.9).ConclusionAlthough the increase in absolute risk of suicide was modest, our findings reflect the severe psychological stress that prostate cancer patients may experience after diagnosis. The increased risk of suicide observed in men with prostate cancer, including low-risk, calls for increased awareness.     

Association of Metformin,Other Antidiabetic Medications,and Statins With Incidence of Colon Cancer in Patients With Type 2 Diabetes

BackgroundMetformin and statins may have anticancer effects, with plausible cellular mechanisms. However, the association of these agents with the risk of colorectal cancer is unclear.Patients and MethodsThis was a retrospective cohort study on a large population (N = 316,317) of patients with type 2 diabetes. Data were obtained from the Diabetes in Finland database (FinDM). In a full cohort analysis, hazard ratios (HRs) with their 95% confidence intervals (CIs) for ever use versus never use were estimated using a multiple Poisson regression model. A nested case–control design within the cohort was used to examine the association of colon cancer (CC) with the defined daily dose of medication. The data were analyzed by conditional logistic regression. The analyses were adjusted for the patient’s age, sex, and duration of diabetes.ResultsIn total, 1351 CC cases were diagnosed during 1996-2011. The results revealed insufficient evidence for an association between metformin (HR, 1.01; 95% CI, 0.90-1.14), other oral antidiabetic medications (HR, 1.05; 95% CI, 0.93-1.19), insulin (HR, 1.02; 95% CI, 0.86-1.22), or statins (HR, 0.94; 95% CI, 0.84-1.05) and the incidence of CC in the full cohort analysis. The results from the case–control study were similar, with no consistent trend in the incidence of CC according to the cumulative dose of metformin or the other studied medications.ConclusionThis study found insufficient evidence for an association between metformin, insulin, other oral type 2 diabetes medications, or statins and the incidence of CC.