TMPRSS2:ERG gene fusion associated with lethal prostate cancer in a watchful waiting cohort

The identification of the TMPRSS2:ERG fusion in prostate cancer suggests that distinct molecular subtypes may define risk for disease progression. In surgical series, TMPRSS2:ERG fusion was identified in 50% of the tumors. Here, we report on a population-based cohort of men with localized prostate cancers followed by expectant (watchful waiting) therapy with 15% (17/111) TMPRSS2:ERG fusion. We identified a statistically significant association between TMPRSS2:ERG fusion and prostate cancer specific death (cumulative incidence ratio=2.7, P<0.01, 95% confidence interval=1.3-5.8). Quantitative reverse-transcription-polymerase chain reaction demonstrated high ets-related [corrected] gene (ERG) expression to be associated with TMPRSS2:ERG fusion (P<0.005). These data suggest that TMPRSS2:ERG fusion prostate cancers may have a more aggressive phenotype, possibly mediated through increased ERG expression.

Suicide and cardiovascular death after a cancer diagnosis

BACKGROUND

Receiving a diagnosis of cancer is a traumatic experience that may trigger immediate adverse health consequences beyond the effects of the disease or treatment.

METHODS

Using Poisson and negative binomial regression models, we conducted a historical cohort study involving 6,073,240 Swedes to examine the associations between a cancer diagnosis and the immediate risk of suicide or death from cardiovascular causes from 1991 through 2006. To adjust for unmeasured confounders, we also performed a nested, self-matched case-crossover analysis among all patients with cancer who died from suicide or cardiovascular diseases in the cohort.

RESULTS

As compared with cancer-free persons, the relative risk of suicide among patients receiving a cancer diagnosis was 12.6 (95% confidence interval [CI], 8.6 to 17.8) during the first week (29 patients; incidence rate, 2.50 per 1000 person-years) and 3.1 (95% CI, 2.7 to 3.5) during the first year (260 patients; incidence rate, 0.60 per 1000 person-years). The relative risk of cardiovascular death after diagnosis was 5.6 (95% CI, 5.2 to 5.9) during the first week (1318 patients; incidence rate, 116.80 per 1000 person-years) and 3.3 (95% CI, 3.1 to 3.4) during the first 4 weeks (2641 patients; incidence rate, 65.81 per 1000 person-years). The risk elevations decreased rapidly during the first year after diagnosis. Increased risk was particularly prominent for cancers with a poor prognosis. The case-crossover analysis largely confirmed results from the main analysis.

CONCLUSIONS

In this large cohort study, patients who had recently received a cancer diagnosis had increased risks of both suicide and death from cardiovascular causes, as compared with cancer-free persons. (Funded by the Swedish Council for Working Life and Social Research and others.).

The role of SPINK1 in ETS rearrangement-negative prostate cancers

ETS gene fusions have been characterized in a majority of prostate cancers; however, the key molecular alterations in ETS-negative cancers are unclear. Here we used an outlier meta-analysis (meta-COPA) to identify SPINK1 outlier expression exclusively in a subset of ETS rearrangement-negative cancers ( approximately 10% of total cases). We validated the mutual exclusivity of SPINK1 expression and ETS fusion status, demonstrated that SPINK1 outlier expression can be detected noninvasively in urine, and observed that SPINK1 outlier expression is an independent predictor of biochemical recurrence after resection. We identified the aggressive 22RV1 cell line as a SPINK1 outlier expression model and demonstrate that SPINK1 knockdown in 22RV1 attenuates invasion, suggesting a functional role in ETS rearrangement-negative prostate cancers.

Estrogen-dependent signaling in a molecularly distinct subclass of aggressive prostate cancer

BACKGROUND

The majority of prostate cancers harbor gene fusions of the 5'-untranslated region of the androgen-regulated transmembrane protease serine 2 (TMPRSS2) promoter with erythroblast transformation-specific transcription factor family members. The common fusion between TMPRESS2 and v-ets erythroblastosis virus E26 oncogene homolog (avian) (ERG) is associated with a more aggressive clinical phenotype, implying the existence of a distinct subclass of prostate cancer defined by this fusion.

METHODS

We used complementary DNA-mediated annealing, selection, ligation, and extension to determine the expression profiles of 6144 transcriptionally informative genes in archived biopsy samples from 455 prostate cancer patients in the Swedish Watchful Waiting cohort (1987-1999) and the United States-based Physicians(') Health Study cohort (1983-2003). A gene expression signature for prostate cancers with the TMPRSS2-ERG fusion was determined using partitioning and classification models and used in computational functional analysis. Cell proliferation and TMPRSS2-ERG expression in androgen receptor-negative (NCI-H660) prostate cancer cells after treatment with vehicle or estrogenic compounds were assessed by viability assays and quantitative polymerase chain reaction, respectively. All statistical tests were two-sided.

RESULTS

We identified an 87-gene expression signature that distinguishes TMPRSS2-ERG fusion prostate cancer as a discrete molecular entity (area under the curve = 0.80, 95% confidence interval [CI] = 0.792 to 0.81; P < .001). Computational analysis suggested that this fusion signature was associated with estrogen receptor (ER) signaling. Viability of NCI-H660 cells decreased after treatment with estrogen (viability normalized to day 0, estrogen vs vehicle at day 8, mean = 2.04 vs 3.40, difference = 1.36, 95% CI = 1.12 to 1.62) or ERbeta agonist (ERbeta agonist vs vehicle at day 8, mean = 1.86 vs 3.40, difference = 1.54, 95% CI = 1.39 to 1.69) but increased after ERalpha agonist treatment (ERalpha agonist vs vehicle at day 8, mean = 4.36 vs 3.40, difference = 0.96, 95% CI = 0.68 to 1.23). Similarly, expression of TMPRSS2-ERG decreased after ERbeta agonist treatment (fold change over internal control, ERbeta agonist vs vehicle at 24 hours, NCI-H660, mean = 0.57- vs 1.0-fold, difference = 0.43-fold, 95% CI = 0.29- to 0.57-fold) and increased after ERalpha agonist treatment (ERalpha agonist vs vehicle at 24 hours, mean = 5.63- vs 1.0-fold, difference = 4.63-fold, 95% CI = 4.34- to 4.92-fold).

CONCLUSIONS

TMPRSS2-ERG fusion prostate cancer is a distinct molecular subclass. TMPRSS2-ERG expression is regulated by a novel ER-dependent mechanism.

Association of Stress-Related Disorders With Subsequent Autoimmune Disease

IMPORTANCE

Psychiatric reactions to life stressors are common in the general population and may result in immune dysfunction. Whether such reactions contribute to the risk of autoimmune disease remains unclear.

OBJECTIVE

To determine whether there is an association between stress-related disorders and subsequent autoimmune disease.

DESIGN, SETTING, AND PARTICIPANTS

Population- and sibling-matched retrospective cohort study conducted in Sweden from January 1, 1981, to December 31, 2013. The cohort included 106 464 exposed patients with stress-related disorders, with 1 064 640 matched unexposed persons and 126 652 full siblings of these patients.

EXPOSURES

Diagnosis of stress-related disorders, ie, posttraumatic stress disorder, acute stress reaction, adjustment disorder, and other stress reactions.

MAIN OUTCOMES AND MEASURES

Stress-related disorder and autoimmune diseases were identified through the National Patient Register. The Cox model was used to estimate hazard ratios (HRs) with 95% CIs of 41 autoimmune diseases beyond 1 year after the diagnosis of stress-related disorders, controlling for multiple risk factors.

RESULTS

The median age at diagnosis of stress-related disorders was 41 years (interquartile range, 33-50 years) and 40% of the exposed patients were male. During a mean follow-up of 10 years, the incidence rate of autoimmune diseases was 9.1, 6.0, and 6.5 per 1000 person-years among the exposed, matched unexposed, and sibling cohorts, respectively (absolute rate difference, 3.12 [95% CI, 2.99-3.25] and 2.49 [95% CI, 2.23-2.76] per 1000 person-years compared with the population- and sibling-based reference groups, respectively). Compared with the unexposed population, patients with stress-related disorders were at increased risk of autoimmune disease (HR, 1.36 [95% CI, 1.33-1.40]). The HRs for patients with posttraumatic stress disorder were 1.46 (95% CI, 1.32-1.61) for any and 2.29 (95% CI, 1.72-3.04) for multiple (≥3) autoimmune diseases. These associations were consistent in the sibling-based comparison. Relative risk elevations were more pronounced among younger patients (HR, 1.48 [95% CI, 1.42-1.55]; 1.41 [95% CI, 1.33-1.48]; 1.31 [95% CI, 1.24-1.37]; and 1.23 [95% CI, 1.17-1.30] for age at ≤33, 34-41, 42-50, and ≥51 years, respectively; P for interaction < .001). Persistent use of selective serotonin reuptake inhibitors during the first year of posttraumatic stress disorder diagnosis was associated with attenuated relative risk of autoimmune disease (HR, 3.64 [95% CI, 2.00-6.62]; 2.65 [95% CI, 1.57-4.45]; and 1.82 [95% CI, 1.09-3.02] for duration ≤179, 180-319, and ≥320 days, respectively; P for trend = .03).

CONCLUSIONS AND RELEVANCE

In this Swedish cohort, exposure to a stress-related disorder was significantly associated with increased risk of subsequent autoimmune disease, compared with matched unexposed individuals and with full siblings. Further studies are needed to better understand the underlying mechanisms.

Molecular sampling of prostate cancer: a dilemma for predicting disease progression

BACKGROUND

Current prostate cancer prognostic models are based on pre-treatment prostate specific antigen (PSA) levels, biopsy Gleason score, and clinical staging but in practice are inadequate to accurately predict disease progression. Hence, we sought to develop a molecular panel for prostate cancer progression by reasoning that molecular profiles might further improve current clinical models.

METHODS

We analyzed a Swedish Watchful Waiting cohort with up to 30 years of clinical follow up using a novel method for gene expression profiling. This cDNA-mediated annealing, selection, ligation, and extension (DASL) method enabled the use of formalin-fixed paraffin-embedded transurethral resection of prostate (TURP) samples taken at the time of the initial diagnosis. We determined the expression profiles of 6100 genes for 281 men divided in two extreme groups: men who died of prostate cancer and men who survived more than 10 years without metastases (lethals and indolents, respectively). Several statistical and machine learning models using clinical and molecular features were evaluated for their ability to distinguish lethal from indolent cases.

RESULTS

Surprisingly, none of the predictive models using molecular profiles significantly improved over models using clinical variables only. Additional computational analysis confirmed that molecular heterogeneity within both the lethal and indolent classes is widespread in prostate cancer as compared to other types of tumors.

CONCLUSIONS

The determination of the molecularly dominant tumor nodule may be limited by sampling at time of initial diagnosis, may not be present at time of initial diagnosis, or may occur as the disease progresses making the development of molecular biomarkers for prostate cancer progression challenging.

Clinical Diagnosis of Mental Disorders Immediately Before and After Cancer Diagnosis: A Nationwide Matched Cohort Study in Sweden

IMPORTANCE

Psychiatric comorbidities are common among patients with cancer. However, whether or not there is increased risk of mental disorders during the diagnostic workup leading to a cancer diagnosis was unknown.

OBJECTIVE

To examine the relative risks of depression, anxiety, substance abuse, somatoform/conversion disorder, and stress reaction/adjustment disorder during the periods before and after cancer diagnosis compared with individuals without cancer.

DESIGN, SETTING, AND PARTICIPANTS

Nationwide matched cohort study from January 1, 2001, to December 31, 2010, in a Swedish population and health registers.

MAIN OUTCOMES AND MEASURES

We estimated the time-varying hazard ratios (HRs) of the first clinical diagnosis of the studied mental disorders from 2 years before cancer diagnosis, through the time of diagnosis, and until 10 years after diagnosis, adjusting for age, sex, calendar period, and educational level. To assess milder mental conditions and symptoms, we further assessed the use of related psychiatric medications for patients with cancer diagnosed during 2008-2009.

RESULTS

The study included 304 118 patients with cancer and 3 041 174 cancer-free individuals who were randomly selected from the Swedish population and individually matched to the patients with cancer on year of birth and sex. The median age at diagnosis for the patients with cancer was 69 years, and 46.9% of the patients were female. The relative rate for all studied mental disorders started to increase from 10 months before cancer diagnosis (HR, 1.1; 95% CI, 1.1-1.2), peaked during the first week after diagnosis (HR, 6.7; 95% CI, 6.1-7.4), and decreased rapidly thereafter but remained elevated 10 years after diagnosis (HR, 1.1; 95% CI, 1.1-1.2). The rate elevation was clear for all main cancers except nonmelanoma skin cancer and was stronger for cancers of poorer prognosis. Compared with cancer-free individuals, increased use of psychiatric medications was noted from 1 month before cancer diagnosis and peaked around 3 months after diagnosis among patients with cancer.

CONCLUSIONS AND RELEVANCE

Patients diagnosed as having cancer had increased risks of several common mental disorders from the year before diagnosis. These findings support the existing guidelines of integrating psychological management into cancer care and further call for extended vigilance for multiple mental disorders starting from the time of the cancer diagnostic workup.

Prospective study of Trichomonas vaginalis infection and prostate cancer incidence and mortality: Physicians' Health Study

BACKGROUND

A recent nested case-control study found that the presence of antibodies against Trichomonas vaginalis, a common nonviral sexually transmitted infection, was positively associated with subsequent incidence of prostate cancer. We confirmed these findings in an independent population and related serostatus for antibodies against T vaginalis to prostate cancer incidence and mortality.

METHODS

We conducted a case-control study nested within the Physicians' Health Study that included 673 case subjects with prostate cancer and 673 individually matched control subjects who had available plasma samples. Plasma from blood samples collected at baseline was assayed for antibodies against T vaginalis with an enzyme-linked immunosorbent assay. We used conditional logistic regression to estimate the odds ratios (ORs) of incident prostate cancer, extraprostatic prostate cancer, and cancer that would ultimately progress to bony metastases or prostate cancer-specific death.

RESULTS

Although not statistically significant, the magnitude of the association between T vaginalis-seropositive status and overall prostate cancer risk (OR = 1.23, 95% confidence interval [CI] = 0.94 to 1.61) was similar to that reported previously. Furthermore, a seropositive status was associated with statistically significantly increased risks of extraprostatic prostate cancer (OR = 2.17, 95% CI = 1.08 to 4.37) and of cancer that would ultimately progress to bony metastases or prostate cancer-specific death (OR = 2.69, 95% CI = 1.37 to 5.28).

CONCLUSIONS

This large prospective case-control study obtained further support for an association between a seropositive status for antibodies against T vaginalis and the risk of prostate cancer, with statistically significant associations identified for the risk of extraprostatic prostate cancer and for clinically relevant, potentially lethal prostate cancer.

Psychological distress among health professional students during the COVID-19 outbreak

BACKGROUND

Due to the drastic surge of COVID-19 patients, many countries are considering or already graduating health professional students early to aid professional resources. We aimed to assess outbreak-related psychological distress and symptoms of acute stress reaction (ASR) in health professional students and to characterize individuals with potential need for interventions.

METHODS

We conducted a prospective cohort study of 1442 health professional students at Sichuan University, China. At baseline (October 2019), participants were assessed for childhood adversity, stressful life events, internet addiction, and family functioning. Using multivariable logistic regression, we examined associations of the above exposures with subsequent psychological distress and ASR in response to the outbreak.

RESULTS

Three hundred and eighty-four (26.63%) participants demonstrated clinically significant psychological distress, while 160 (11.10%) met the criterion for a probable ASR. Individuals who scored high on both childhood adversity and stressful life event experiences during the past year were at increased risks of both distress (ORs 2.00-2.66) and probable ASR (ORs 2.23-3.10), respectively. Moreover, internet addiction was associated with elevated risks of distress (OR 2.05, 95% CI 1.60-2.64) and probable ASR (OR 2.15, 95% CI 1.50-3.10). By contrast, good family functioning was associated with decreased risks of distress (OR 0.43, 95% CI 0.33-0.55) and probable ASR (OR 0.48, 95% CI 0.33-0.69). All associations were independent of baseline psychological distress.

CONCLUSIONS

Our findings suggest that COVID-19 related psychological distress and high symptoms burden of ASR are common among health professional students. Extended family and professional support should be considered for vulnerable individuals during these unprecedented times.

Immediate risk of suicide and cardiovascular death after a prostate cancer diagnosis: cohort study in the United States

BACKGROUND

Receiving a cancer diagnosis is a stressful event that may increase risks of suicide and cardiovascular death, especially soon after diagnosis.

METHODS

We conducted a cohort study of 342,497 patients diagnosed with prostate cancer from January 1, 1979, through December 31, 2004, in the Surveillance, Epidemiology, and End Results Program. Follow-up started from the date of prostate cancer diagnosis to the end of first 12 calendar months after diagnosis. The relative risks of suicide and cardiovascular death were calculated as standardized mortality ratios (SMRs) comparing corresponding incidences among prostate cancer patients with those of the general US male population, with adjustment for age, calendar period, and state of residence. We compared risks in the first year and months after a prostate cancer diagnosis. The analyses were further stratified by calendar period at diagnosis, tumor characteristics, and other variables.

RESULTS

During follow-up, 148 men died of suicide (mortality rate = 0.5 per 1000 person-years) and 6845 died of cardiovascular diseases (mortality rate = 21.8 per 1000 person-years). Patients with prostate cancer were at increased risk of suicide during the first year (SMR = 1.4, 95% confidence interval [CI] = 1.2 to 1.6), especially during the first 3 months (SMR = 1.9, 95% CI = 1.4 to 2.6), after diagnosis. The elevated risk was apparent in pre-prostate-specific antigen (PSA) (1979-1986) and peri-PSA (1987-1992) eras but not since PSA testing has been widespread (1993-2004). The risk of cardiovascular death was slightly elevated during the first year (SMR = 1.09, 95% CI = 1.06 to 1.12), with the highest risk in the first month (SMR = 2.05, 95% CI = 1.89 to 2.22), after diagnosis. The first-month risk was statistically significantly elevated during the entire study period, and the risk was higher for patients with metastatic tumors (SMR = 3.22, 95% CI = 2.68 to 3.84) than for those with local or regional tumors (SMR = 1.57, 95% CI = 1.42 to 1.74).

CONCLUSION

A diagnosis of prostate cancer may increase the immediate risks of suicide and cardiovascular death.

mRNA expression signature of Gleason grade predicts lethal prostate cancer

PURPOSE

Prostate-specific antigen screening has led to enormous overtreatment of prostate cancer because of the inability to distinguish potentially lethal disease at diagnosis. We reasoned that by identifying an mRNA signature of Gleason grade, the best predictor of prognosis, we could improve prediction of lethal disease among men with moderate Gleason 7 tumors, the most common grade, and the most indeterminate in terms of prognosis.

PATIENTS AND METHODS

Using the complementary DNA-mediated annealing, selection, extension, and ligation assay, we measured the mRNA expression of 6,100 genes in prostate tumor tissue in the Swedish Watchful Waiting cohort (n = 358) and Physicians' Health Study (PHS; n = 109). We developed an mRNA signature of Gleason grade comparing individuals with Gleason ≤ 6 to those with Gleason ≥ 8 tumors and applied the model among patients with Gleason 7 to discriminate lethal cases.

RESULTS

We built a 157-gene signature using the Swedish data that predicted Gleason with low misclassification (area under the curve [AUC] = 0.91); when this signature was tested in the PHS, the discriminatory ability remained high (AUC = 0.94). In men with Gleason 7 tumors, who were excluded from the model building, the signature significantly improved the prediction of lethal disease beyond knowing whether the Gleason score was 4 + 3 or 3 + 4 (P = .006).

CONCLUSION

Our expression signature and the genes identified may improve our understanding of the de-differentiation process of prostate tumors. Additionally, the signature may have clinical applications among men with Gleason 7, by further estimating their risk of lethal prostate cancer and thereby guiding therapy decisions to improve outcomes and reduce overtreatment.

Prostate-Specific Antigen Levels as a Predictor of Lethal Prostate Cancer

BACKGROUND

Rates of long-term survival among patients with untreated localized prostate cancer are high. To avoid unnecessary treatment, tools are needed to identify the small proportion of patients who are destined to develop lethal prostate cancer.

METHODS

To evaluate the accuracy of early changes in prostate-specific antigen (PSA) levels as predictors of prostate cancer outcome, we assessed serial measurements of PSA level among 267 men with localized prostate cancer in a Scandinavian cohort of men who were diagnosed between 1989 and 1999 and who were managed by watchful waiting. We then 1) fitted individual regression lines to the PSA values assessed for each patient during the first 2 years of follow-up by using three different models, 2) evaluated early PSA curve characteristics as determinants of the cumulative incidence of lethal prostate cancer and calculated hazard ratios for baseline PSA value and rate of change in PSA level to prostate cancer outcome, and 3) plotted time-dependent receiver operating characteristic (ROC) curves. All P values are two-sided.

RESULTS

During complete follow-up for a mean of 8.5 years, 34 patients (13%) died from prostate cancer, and 18 (7%) developed metastases but were still alive at end of follow-up. In a log-linear model, both PSA value at baseline (P = .05) and the rate of PSA change (P<.001) were associated with the development of lethal prostate cancer. In the ROC analysis, however, the accuracy of classifying the disease as either indolent or destined to progress was low, regardless of the cut point chosen for initial PSA level or rate of change in PSA level.

CONCLUSIONS

Although baseline PSA value and rate of PSA change are prognostic factors for lethal prostate cancer, they are poor predictors of lethal prostate cancer among patients with localized prostate cancer who are managed by watchful waiting.

Circadian disruption, sleep loss, and prostate cancer risk: a systematic review of epidemiologic studies

Disruption of the circadian system has been hypothesized to increase cancer risk, either because of direct disruption of the molecular machinery generating circadian rhythms or because of disruption of parameters controlled by the clock such as melatonin levels or sleep duration. This hypothesis has been studied in hormone-dependent cancers among women, but data are sparse about potential effects of circadian disruption on the risk of prostate cancer. This review systematically examines available data evaluating the effects of light at night, sleep patterns, and night shift work on prostate cancer risk.

Stress related disorders and risk of cardiovascular disease: population based, sibling controlled cohort study

OBJECTIVE

To assess the association between stress related disorders and subsequent risk of cardiovascular disease.

DESIGN

Population based, sibling controlled cohort study.

SETTING

Population of Sweden.

PARTICIPANTS

136 637 patients in the Swedish National Patient Register with stress related disorders, including post-traumatic stress disorder (PTSD), acute stress reaction, adjustment disorder, and other stress reactions, from 1987 to 2013; 171 314 unaffected full siblings of these patients; and 1 366 370 matched unexposed people from the general population.

MAIN OUTCOME MEASURES

Primary diagnosis of incident cardiovascular disease—any or specific subtypes (ischaemic heart disease, cerebrovascular disease, emboli/thrombosis, hypertensive diseases, heart failure, arrhythmia/conduction disorder, and fatal cardiovascular disease)—and 16 individual diagnoses of cardiovascular disease. Hazard ratios for cardiovascular disease were derived from Cox models, after controlling for multiple confounders.

RESULTS

During up to 27 years of follow-up, the crude incidence rate of any cardiovascular disease was 10.5, 8.4, and 6.9 per 1000 person years among exposed patients, their unaffected full siblings, and the matched unexposed individuals, respectively. In sibling based comparisons, the hazard ratio for any cardiovascular disease was 1.64 (95% confidence interval 1.45 to 1.84), with the highest subtype specific hazard ratio observed for heart failure (6.95, 1.88 to 25.68), during the first year after the diagnosis of any stress related disorder. Beyond one year, the hazard ratios became lower (overall 1.29, 1.24 to 1.34), ranging from 1.12 (1.04 to 1.21) for arrhythmia to 2.02 (1.45 to 2.82) for artery thrombosis/embolus. Stress related disorders were more strongly associated with early onset cardiovascular diseases (hazard ratio 1.40 (1.32 to 1.49) for attained age <50) than later onset ones (1.24 (1.18 to 1.30) for attained age ≥50; P for difference=0.002). Except for fatal cardiovascular diseases, these associations were not modified by the presence of psychiatric comorbidity. Analyses within the population matched cohort yielded similar results (hazard ratio 1.71 (1.59 to 1.83) for any cardiovascular disease during the first year of follow-up and 1.36 (1.33 to 1.39) thereafter).

CONCLUSION

Stress related disorders are robustly associated with multiple types of cardiovascular disease, independently of familial background, history of somatic/psychiatric diseases, and psychiatric comorbidity.

How well does the Gleason score predict prostate cancer death? A 20-year followup of a population based cohort in Sweden

PURPOSE

Adenocarcinoma of the prostate is the most common cancer among men in Western countries. Although the prognostic heterogeneity of prostate cancer is enormous, clinically insignificant aggressive prostate cancers cannot be reliably distinguished. Therefore, identifying prognostic factors is increasingly important, notably among men diagnosed with localized prostate cancer, because many of them may not require aggressive treatment.

MATERIALS AND METHODS

We analyzed a population based cohort of 253 men with early stage (T1a-b, Nx, M0) initially untreated prostate cancer diagnosed between 1977 and 1991, before PSA screening was available. Tissue samples were available for 240 patients diagnosed with transurethral resection. During complete followup through September 2003, standardized criteria were used to classify histopathological characteristics, progression and causes of death.

RESULTS

Higher Gleason grade, higher nuclear grade and larger tumor volume were independent predictors of death in prostate cancer with monotonous and statistically significant trends (p <0.05). In contrast, the level of Ki-67 - strongly correlated to Gleason score - was not an independent predictor of prostate cancer death. Given a Gleason score of 7 or greater, the probability of dying of prostate cancer was 29%. The corresponding predictive value for Gleason score 8 or greater was 48%.

CONCLUSIONS

Although a high Gleason score is a determinant of prostate cancer death, its PPV is relatively low. Thus, further efforts in finding other or complementary indicators of prostate cancer outcome are needed.

Reliability of death certificates in prostate cancer patients

OBJECTIVE

To evaluate the reliability of cause-of-death diagnoses among prostate cancer patients.

MATERIAL AND METHODS

Information from death certificates obtained from the Swedish Death Register was compared with systematically reviewed medical records from the population-based Swedish Regional Prostate Cancer Register, South-East Region. In total, 5675 patients were included who had been diagnosed with prostate cancer between 1987 and 1999 and who had died before 1 January 2003.

RESULTS

The proportion of prostate cancer cases classified as having died from prostate cancer was 3% higher in the official death certificates than in the reviewed records [0.03, 95% confidence interval (CI) 0.02 to 0.04]. Overall agreement between the official cause of death and the reviewed data was 86% (95% CI 85 to 87%). A higher accuracy was observed among men with localized disease (88%, 95% CI 87 to 89%), aged 60 years or younger at death (96%, 95% CI 93 to 100%), or who had undergone curative treatment (91%, 95% CI 88 to 95%). This study indicates a relatively high reliability of official cause-of-death statistics of prostate cancer patients in Sweden.

CONCLUSION

Mortality data obtained from death certificates may be useful in the evaluation of large-scale prostate cancer intervention programmes, especially among younger patients with localized disease.

Immediate risk for cardiovascular events and suicide following a prostate cancer diagnosis: prospective cohort study

BACKGROUND

Stressful life events have been shown to be associated with altered risk of various health consequences. The aim of the present study was to investigate whether the emotional stress evoked by a prostate cancer diagnosis increases the immediate risks of cardiovascular events and suicide.

METHODS AND FINDINGS

We conducted a prospective cohort study by following all men in Sweden who were 30 y or older (n = 4,305,358) for a diagnosis of prostate cancer (n = 168,584) and their subsequent occurrence of cardiovascular events and suicide between January 1, 1961 and December 31, 2004. We used Poisson regression models to calculate relative risks (RRs) and 95% confidence intervals (CIs) of cardiovascular events and suicide among men who had prostate cancer diagnosed within 1 y to men without any cancer diagnosis. The risks of cardiovascular events and suicide were elevated during the first year after prostate cancer diagnosis, particularly during the first week. Before 1987, the RR of fatal cardiovascular events was 11.2 (95% CI 10.4-12.1) during the first week and 1.9 (95% CI 1.9-2.0) during the first year after diagnosis. From 1987, the RR for cardiovascular events, nonfatal and fatal combined, was 2.8 (95% CI 2.5-3.2) during the first week and 1.3 (95% CI 1.3-1.3) during the first year after diagnosis. While the RR of cardiovascular events declined, the RR of suicide was stable over the entire study period: 8.4 (95% CI 1.9-22.7) during the first week and 2.6 (95% CI 2.1-3.0) during the first year after diagnosis. Men 54 y or younger at cancer diagnosis demonstrated the highest RRs of both cardiovascular events and suicide. A limitation of the present study is the lack of tumor stage data, which precluded possibilities of investigating the potential impact of the disease severity on the relationship between a recent diagnosis of prostate cancer and the risks of cardiovascular events and suicide. In addition, we cannot exclude residual confounding as a possible explanation.

CONCLUSIONS

Men newly diagnosed with prostate cancer are at increased risks for cardiovascular events and suicide. Future studies with detailed disease characteristic data are warranted.

Amyotrophic lateral sclerosis in Sweden, 1991-2005

OBJECTIVES

To investigate the temporal trend of amyotrophic lateral sclerosis (ALS) incidence in Sweden between January 1, 1991, and December 31, 2005, and to explore incidence variations according to major demographic factors.

DESIGN

Population-based study.

SETTING

Academic research.

PARTICIPANTS

All incident cases of ALS identified through the Swedish Inpatient Register between January 1, 1991, and December 31, 2005.

MAIN OUTCOME MEASURE

Age-standardized incidence rates were calculated by applying the observed age-specific incidence rates to the age distribution of the Swedish population in 1991. A linear regression model was used to assess the potential trend of the incidence during calendar years. We also followed up the entire population registered in the 1990 Population and Housing Census for incidence of ALS. Relative risk and 95% confidence interval of ALS associated with demographic variables were estimated using Poisson regression models.

RESULTS

The age-standardized incidence rates increased from 2.32 per 100,000 person-years in 1991-1993 to 2.98 per 100,000 person-years in 2003-2005, representing an annual increase of approximately 2% during the 15 years (P value for trend, .002). The age-specific incidence rates increased in all age groups except those younger than 50 years. The observed increase remained significant when restricting the analysis to individuals born in Sweden (P value for trend, <.001). Compared with individuals born from April through June, those born from October through December were at 11% increased risk of ALS (95% confidence interval, 1.01-1.23).

CONCLUSIONS

The incidence of ALS has been increasing during the last 15 years in Sweden. Further studies are warranted to explore the underlying reasons for this observed trend.

First-onset mental disorders after cancer diagnosis and cancer-specific mortality: a nationwide cohort study

Background

The diagnosis of cancer is strongly associated with the risk of mental disorders even in patients with no previous history of mental disorders. Accumulating data suggest that mental distress may accelerate tumor progression. We hypothesized therefore that mental disorders after a cancer diagnosis may increase the risk of cancer-specific mortality.

Patients and methods

We conducted a nationwide cohort study including 244 261 cancer patients diagnosed in Sweden during 2004-2009 and followed them through 2010. Through the Swedish Patient Register, we obtained clinical diagnoses of all mental disorders and focused on mood-, anxiety-, and substance abuse disorders (ICD10: F10-F16, F18-F19, F32-F33, F40-F41, and F43-45) that are commonly diagnosed among patients with cancer. We further classified the studied mental disorders into first-onset or recurrent mental disorders. We used Cox regression to estimate multivariable hazard ratios (HRs) with 95% confidence intervals (CIs) as a measure of the association between mental disorders after cancer diagnosis and cancer-specific mortality, adjusting for age, sex, calendar period, educational level, cancer stage, and cancer type at diagnosis.

Results

After cancer diagnosis, 11 457 patients were diagnosed with mood-, anxiety-, and substance abuse disorders; of which 7236 were first-onset mental disorders. Patients with a first-onset mental disorder were at increased risk of cancer-specific mortality (HR: 1.82, 95% CI: 1.71-1.92) while patients with a recurrent mental disorder had much lower risk elevation (HR: 1.14, 95% CI: 1.05-1.24). The increased cancer-specific mortality by first-onset mental disorders was observed for almost all cancer sites/groups and the association was stronger for localized cancers (HR: 2.00, 95% CI: 1.73-2.31) than for advanced cancers (HR: 1.49, 95% CI: 1.32-1.69).

Conclusions

Patients with a first-onset common mood-, anxiety-, or substance abuse disorder after cancer diagnosis may be at increased risk of cancer-specific death.

Early Exposure to Dogs and Farm Animals and the Risk of Childhood Asthma

IMPORTANCE

The association between early exposure to animals and childhood asthma is not clear, and previous studies have yielded contradictory results.

OBJECTIVE

To determine whether exposure to dogs and farm animals confers a risk of asthma.

DESIGN, SETTING AND PARTICIPANTS

In a nationwide cohort study, the association between early exposure to dogs and farm animals and the risk of asthma was evaluated and included all children born in Sweden from January 1, 2001, to December 31, 2010 (N = 1,011,051), using registry data on dog and farm registration, asthma medication, diagnosis, and confounders for parents and their children. The association was assessed as the odds ratio (OR) for a current diagnosis of asthma at age 6 years for school-aged children and as the hazard ratio (HR) for incident asthma at ages 1 to 5 years for preschool-aged children. Data were analyzed from January 1, 2007, to September 30, 2012.

EXPOSURES

Living with a dog or farm animal.

MAIN OUTCOMES AND MEASURES

Childhood asthma diagnosis and medication used.

RESULTS

Of the 1,011,051 children born during the study period, 376,638 preschool-aged (53,460 [14.2%] exposed to dogs and 1729 [0.5%] exposed to farm animals) and 276,298 school-aged children (22,629 [8.2%] exposed to dogs and 958 [0.3%] exposed to farm animals) were included in the analyses. Of these, 18,799 children (5.0%) in the preschool-aged children's cohort experienced an asthmatic event before baseline, and 28,511 cases of asthma and 906,071 years at risk were recorded during follow-up (incidence rate, 3.1 cases per 1000 years at risk). In the school-aged children's cohort, 11,585 children (4.2%) experienced an asthmatic event during the seventh year of life. Dog exposure during the first year of life was associated with a decreased risk of asthma in school-aged children (OR, 0.87; 95% CI, 0.81-0.93) and in preschool-aged children 3 years or older (HR, 0.90; 95% CI, 0.83-0.99) but not in children younger than 3 years (HR, 1.03; 95% CI, 1.00-1.07). Results were comparable when analyzing only first-born children. Farm animal exposure was associated with a reduced risk of asthma in both school-aged children and preschool-aged children (OR, 0.48; 95% CI, 0.31-0.76, and HR, 0.69; 95% CI, 0.56-0.84), respectively.

CONCLUSIONS AND RELEVANCE

In this study, the data support the hypothesis that exposure to dogs and farm animals during the first year of life reduces the risk of asthma in children at age 6 years. This information might be helpful in decision making for families and physicians on the appropriateness and timing of early animal exposure.

Sleep disruption among older men and risk of prostate cancer

BACKGROUND

Although positive associations have consistently been reported between sleep disruption and breast cancer, less is known about its potential role in prostate cancer.

METHODS

Within the prospective AGES-Reykjavik cohort study, we followed 2,102 men recruited in 2002-2006 until the end of 2009. Participants answered questions on sleep disruption. Information on the occurrence of prostate cancer was obtained through record linkages across the Icelandic Cancer Registry. We used Cox regression models with 95% confidence intervals (CI) to estimate HRs of prostate cancer by symptoms of sleep disruption.

RESULTS

During follow-up, 135 men (6.4%) were diagnosed with prostate cancer. Compared with men without sleep disruption, those with problems falling and staying asleep were at significantly increased risk of prostate cancer [HR, 1.7 (95% CI, 1.0-2.9) and 2.1 (95% CI, 1.2-3.7)], respectively, with increasing sleep disruption severity. When restricted to advanced prostate cancer (≥ stage T3 or lethal disease), these associations became even stronger [HR 2.1 (95% CI, 0.7-6.2) and 3.2 (95% CI, 1.1-9.7)]. The results did not change after excluding from the analyses men who woke up during the night, indicative of nocturia, suggesting limited risk of reverse association.

CONCLUSIONS

Our data suggest that certain aspects of sleep disruption may confer an increased risk of prostate cancer and call for additional, larger studies with longer follow-up times.

IMPACT

Prostate cancer is one of the leading public health concerns in men; if confirmed in future studies, the association between sleep disruption and prostate cancer risk may open new avenues for prevention.

An exploration of shared genetic risk factors between periodontal disease and cancers: a prospective co-twin study

Biologic mechanisms underlying associations of periodontal disease with cancers remain unknown. The authors propose that both conditions share common genetic risk factors. They analyzed associations between baseline periodontal disease, measured by questionnaire-recorded tooth mobility, and incident cancers, identified by linkage with national registries, between 1963 and 2004 in 15,333 Swedish twins. The authors used co-twin analyses to control for familial factors and undertook analyses restricted to monozygotic twins to further control for confounding by genetic factors. They observed 4,361 cancer cases over 548,913 person-years. After adjustment for covariates, baseline periodontal disease was associated with increased risk of several cancers ranging from 15% for total cancer (proportional hazard ratio (HR) = 1.15, 95% confidence interval (CI): 1.01, 1.32) to 120% for corpus uterine cancer (HR = 2.20, 95% CI: 1.16, 4.18). Periodontal disease was also associated with increased risk of colorectal (HR = 1.62, 95% CI: 1.13, 2.33), pancreatic (HR = 2.06, 95% CI: 1.14, 3.75), and prostate (HR = 1.47, 95% CI: 1.04, 2.07) cancers. In co-twin analyses, dizygotic twins with baseline periodontal disease showed a 50% increase in total cancer risk (HR = 1.50, 95% CI: 1.04, 2.17), but in monozygotic twins this association was markedly attenuated (HR = 1.07, 95% CI: 0.63, 1.81). Similar patterns emerged for digestive tract cancers, suggesting that shared genetic risk factors may partially explain associations between periodontal disease and cancers.

Prevalence and incidence of diabetes mellitus: a nationwide population-based pharmaco-epidemiological study in Sweden

AIM

To investigate the changes in prevalence and incidence of pharmacologically and non-pharmacologically treated diabetes in Sweden during 2005 to 2013.

METHODS

We obtained data on gender, date of birth and pharmacologically and non-pharmacologically treated diabetes from national registers for all Swedish residents.

RESULTS

During the study period a total of 240 871 new cases of pharmacologically treated diabetes was found. The age-standardized incidence during the follow-up was 4.34 and 3.16 per 1000 individuals in men and women, respectively. A decreasing time trend in incidence for men of 0.6% per year (0.994, 95% CI 0.989-0.999) and for women of 0.7% per year (0.993, 95% CI 0.986-0.999) was observed. The age-standardized prevalence increased from 41.9 and 29.9 per 1000 in 2005/2006 to 50.8 and 34.6 in 2012/2013 in men and women, respectively. This corresponds to an annually increasing time trend for both men (1.024, 95% CI 1.022-1.027) and women (1.019, 95% CI 1.016-1.021). The total age-standardized prevalence of pharmacologically and non-pharmacologically treated diabetes (2012) was 46.9 per 1000 (55.6 for men and 38.8 for women). This corresponds to an annually increasing time trend (2010-2012) for both men (1.017, 95% CI 1.013-1.021) and women (1.012, 95% CI 1.008-1.016).

CONCLUSIONS

The prevalence of pharmacologically treated diabetes increased moderately during 8 years of follow-up, while the incidence decreased modestly. This is in contrast to the results reported by most other studies. The total prevalence of diabetes (both pharmacologically and non-pharmacologically treated) in Sweden is relatively low, from a global viewpoint.

Prediagnostic plasma vitamin D metabolites and mortality among patients with prostate cancer

BACKGROUND

Laboratory evidence suggests that vitamin D might influence prostate cancer prognosis.

METHODOLOGY/PRINCIPAL FINDINGS

We examined the associations between prediagnostic plasma levels of 25(OH)vitamin D [25(OH)D] and 1,25(OH)(2) vitamin D [1,25(OH)(2)D] and mortality among 1822 participants of the Health Professionals Follow-up Study and Physicians' Health Study who were diagnosed with prostate cancer. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of total mortality (n = 595) and lethal prostate cancer (death from prostate cancer or development of bone metastases; n = 202). In models adjusted for age at diagnosis, BMI, physical activity, and smoking, we observed a HR of 1.22 (95% CI: 0.97, 1.54) for total mortality, comparing men in the lowest to the highest quartile of 25(OH)D. There was no association between 1,25(OH)(2)D and total mortality. Men with the lowest 25(OH)D quartile were more likely to die of their cancer (HR: 1.59; 95% CI: 1.06, 2.39) compared to those in the highest quartile (P(trend) = 0.006). This association was largely explained by the association between low 25(OH)D levels and advanced cancer stage and higher Gleason score, suggesting that these variables may mediate the influence of 25(OH)D on prognosis. The association also tended to be stronger among patients with samples collected within five years of cancer diagnosis. 1,25(OH)(2)D levels were not associated with lethal prostate cancer.

CONCLUSIONS/SIGNIFICANCE

Although potential bias of less advanced disease due to more screening activity among men with high 25(OH)D levels cannot be ruled out, higher prediagnostic plasma 25(OH)D might be associated with improved prostate cancer prognosis.

CD4 helper T cells, CD8 cytotoxic T cells, and FOXP3(+) regulatory T cells with respect to lethal prostate cancer

Prostate cancer represents a major contributor to cancer mortality, but the majority of men with prostate cancer will die of other causes. Thus, a challenge is identifying potentially lethal disease at diagnosis. Conflicting results have been reported when investigating the relationship between infiltration of lymphocytes and survival in prostate cancer. One of the mechanisms suggested is the recruitment of regulatory T cells (T(regs)), a subpopulation of T cells that have a role in promoting tumor growth. T(regs) counteract tumor rejection through suppressive functions on the anti-immune response but their prognostic significance is still unknown. We report here the results of a conducted case-control study nested in a cohort of men treated with transurethral resection of the prostate and diagnosed incidentally with prostate cancer. Cases are men who died of prostate cancer (n=261) and controls are men who survived >10 years after their diagnosis (n=474). Infiltration of both T(helper) and T(cytotoxic) cells was frequently observed and the majority of the T(regs) were CD4(+). T(helper) or T(cytotoxic) cells were not associated with lethal prostate cancer. However, we found a nearly twofold increased risk of lethal prostate cancer when comparing the highest with the lowest quartile of CD4(+) T(regs) cells (95% confidence interval: 1.3-2.9). Our conclusion is that men with greater numbers of CD4(+) T(regs) in their prostate tumor environment have an increased risk of dying of prostate cancer. Identification of CD4(+) T(regs) in tumor tissue may predict clinically relevant disease at time of diagnosis independently of other clinical factors.