Breast Density and Risk of Interval Cancers: The Effect of Annual Versus Biennial Screening Mammography Policies in Canada.

Regular screening mammography reduces breast cancer mortality. However, in women with dense breasts, the performance of screening mammography is reduced, which is reflected in higher interval cancer rates (ICR). In Canada, population-based screening mammography programs generally screen women biennially; however, some provinces and territories offer annual mammography for women with dense breast tissue routinely and/or on recommendation of the radiologist. This study compared the ICRs in those breast screening programs with a policy of annual vs. those with biennial screening for women with dense breasts. Among 148,575 women with dense breasts screened between 2008 to 2010, there were 288 invasive interval breast cancers; screening programs with policies offering annual screening for women with dense breasts had fewer interval cancers 63/70,814 (ICR 0.89/1000, 95% CI: 0.67-1.11) compared with those with policies of usual biennial screening 225/77,761 (ICR 1.45 /1000 (annualized), 95% CI: 1.19-1.72) i.e. 63% higher (p = 0.0016). In screening programs where radiologists' screening recommendations were able to be analyzed, a total of 76,103 women were screened, with 87 interval cancers; the ICR was lower for recommended annual (65/69,650, ICR 0.93/1000, 95% CI: 0.71, 1.16) versus recommended biennial screening (22/6,453, ICR 1.70/1000 (annualized), 95%CI: 0.70, 2.71)(p = 0.0605). Screening program policies of annual as compared with biennial screening in women with dense breasts had the greatest impact on reducing interval cancer rates. We review our results in the context of current dense breast notification in Canada.

Transforming Canada's role in global cancer control.

Cancer has not been an explicit priority of Canada's international health and development agenda, but it is key to realising the country's Sustainable Development Goal commitments. Multiple converging political, health, and social forces could now drive support for a more integrated Canadian approach to global cancer control. Success will depend on the extent to which Canadian leaders and institutions can build consensus as a community and agree to work together. Collaboration should include agreement on the framing and prioritisation of the core issues, building a broad coalition base, aligning with priorities of international partners, and on a governance structure that reflects the principles of equity, diversity, and inclusion. This Series paper will discuss global cancer control within Canada's global health agenda, how Canada can address its history of colonisation and present-day disparities in its global work, and the challenges and opportunities of creating a Canadian global cancer control network.

Progress in cancer survival, mortality, and incidence in seven high-income countries 1995-2014 (ICBP SURVMARK-2): a population-based study.

BACKGROUND: Population-based cancer survival estimates provide valuable insights into the effectiveness of cancer services and can reflect the prospects of cure. As part of the second phase of the International Cancer Benchmarking Partnership (ICBP), the Cancer Survival in High-Income Countries (SURVMARK-2) project aims to provide a comprehensive overview of cancer survival across seven high-income countries and a comparative assessment of corresponding incidence and mortality trends. METHODS: In this longitudinal, population-based study, we collected patient-level data on 3·9 million patients with cancer from population-based cancer registries in 21 jurisdictions in seven countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway, and the UK) for seven sites of cancer (oesophagus, stomach, colon, rectum, pancreas, lung, and ovary) diagnosed between 1995 and 2014, and followed up until Dec 31, 2015. We calculated age-standardised net survival at 1 year and 5 years after diagnosis by site, age group, and period of diagnosis. We mapped changes in incidence and mortality to changes in survival to assess progress in cancer control. FINDINGS: In 19 eligible jurisdictions, 3 764 543 cases of cancer were eligible for inclusion in the study. In the 19 included jurisdictions, over 1995-2014, 1-year and 5-year net survival increased in each country across almost all cancer types, with, for example, 5-year rectal cancer survival increasing more than 13 percentage points in Denmark, Ireland, and the UK. For 2010-14, survival was generally higher in Australia, Canada, and Norway than in New Zealand, Denmark, Ireland, and the UK. Over the study period, larger survival improvements were observed for patients younger than 75 years at diagnosis than those aged 75 years and older, and notably for cancers with a poor prognosis (ie, oesophagus, stomach, pancreas, and lung). Progress in cancer control (ie, increased survival, decreased mortality and incidence) over the study period was evident for stomach, colon, lung (in males), and ovarian cancer. INTERPRETATION: The joint evaluation of trends in incidence, mortality, and survival indicated progress in four of the seven studied cancers. Cancer survival continues to increase across high-income countries; however, international disparities persist. While truly valid comparisons require differences in registration practice, classification, and coding to be minimal, stage of disease at diagnosis, timely access to effective treatment, and the extent of comorbidity are likely the main determinants of patient outcomes. Future studies are needed to assess the impact of these factors to further our understanding of international disparities in cancer survival. FUNDING: Canadian Partnership Against Cancer; Cancer Council Victoria; Cancer Institute New South Wales; Cancer Research UK; Danish Cancer Society; National Cancer Registry Ireland; The Cancer Society of New Zealand; National Health Service England; Norwegian Cancer Society; Public Health Agency Northern Ireland, on behalf of the Northern Ireland Cancer Registry; The Scottish Government; Western Australia Department of Health; and Wales Cancer Network.

Integrative Population and Physiological Genomics Reveals Mechanisms of Adaptation in Killifish.

Adaptive divergence between marine and freshwater (FW) environments is important in generating phyletic diversity within fishes, but the genetic basis of this process remains poorly understood. Genome selection scans can identify adaptive loci, but incomplete knowledge of genotype-phenotype connections makes interpreting their significance difficult. In contrast, association mapping (genome-wide association mapping [GWAS], random forest [RF] analyses) links genotype to phenotype, but offer limited insight into the evolutionary forces shaping variation. Here, we combined GWAS, RF, and selection scans to identify loci important in adaptation to FW environments. We utilized FW-native and brackish water (BW)-native populations of Atlantic killifish (Fundulus heteroclitus) as well as a naturally admixed population between the two. We measured morphology and multiple physiological traits that differ between populations and may contribute to osmotic adaptation (salinity tolerance, hypoxia tolerance, metabolic rate, body shape) and used a reduced representation approach for genome-wide genotyping. Our results show patterns of population divergence in physiological capabilities that are consistent with local adaptation. Population genomic scans between BW-native and FW-native populations identified genomic regions evolving by natural selection, whereas association mapping revealed loci that contribute to variation for each trait. There was substantial overlap in the genomic regions putatively under selection and loci associated with phenotypic traits, particularly for salinity tolerance, suggesting that these regions and genes are important for adaptive divergence between BW and FW environments. Together, these data provide insight into the mechanisms that enable diversification of fishes across osmotic boundaries.

The osmorespiratory compromise: physiological responses and tolerance to hypoxia are affected by salinity acclimation in the euryhaline Atlantic killifish (Fundulus heteroclitus).

The characteristics of the fish gill that maximize gas exchange are the same that promote diffusion of ions and water to and from the environment; therefore, physiological trade-offs are likely to occur. Here, we investigated how salinity acclimation affects whole-animal respiratory gas exchange during hypoxia using Fundulus heteroclitus, a fish that inhabits salt marshes where salinity and oxygen levels vary greatly. Salinity had marked effects on hypoxia tolerance, with fish acclimated to 11 and 35 ppt showing much longer time to loss of equilibrium (LOE) in hypoxia than 0 ppt-acclimated fish. Fish acclimated to 11 ppt (isosmotic salinity) exhibited the greatest capacity to regulate oxygen consumption rate (MO2 ) under hypoxia, as measured through the regulation index (RI) and Pcrit At 35 ppt, fish had a higher routine metabolic rate (RMR) but a lower RI than fish at 11 ppt, but there were no differences in gill morphology, ventilation or blood O2 transport properties between these groups. In contrast, 0 ppt-acclimated fish had the highest ventilation and lowest O2 extraction efficiency in normoxia and hypoxia, indicating a higher ventilatory workload in order to maintain similar levels of MO2 These differences were related to alterations in gill morphology, where 0 ppt-acclimated fish had the smallest lamellar surface area with the greatest epithelial cell coverage (i.e. thicker lamellae, longer diffusion distance) and a larger interlamellar cell mass, contrasting with 11 ppt-acclimated fish, which had overall the highest respiratory surface area. The alteration of an array of physiological parameters provides evidence for a compromise between salinity and hypoxia tolerance in killifish acclimated to freshwater.

Subspecies differences in thermal acclimation of mitochondrial function and the role of uncoupling proteins in killifish.

Thermal effects on mitochondrial efficiency and ATP production can influence whole-animal thermal tolerance and performance. Thus, organisms may have the capacity to alter mitochondrial processes through acclimation or adaptation to mitigate these effects. One possible mechanism is through the action of uncoupling proteins (UCPs), which can decrease the proton-motive force independent of the production of ATP. To test this hypothesis, we examined the mRNA expression patterns of UCP isoforms and characterized the effects of thermal acclimation and putative local thermal adaptation on mitochondrial capacity, proton leak and P/O ratios in two subspecies of Atlantic killifish (Fundulus heteroclitus). Ucp1 was the dominant isoform in liver and was more highly expressed in northern killifish. We found that cold acclimation increased mitochondrial capacity (state III and maximum substrate oxidation capacity), state II membrane potential, proton leak and P/O ratios in northern, but not southern, killifish liver mitochondria. Palmitate-induced mitochondrial uncoupling was detected in northern, but not southern, killifish liver mitochondria, consistent with the differences in Ucp mRNA expression between the subspecies. Taken together, our data suggest that mitochondrial function is more plastic in response to thermal acclimation in northern killifish than in southern killifish and that UCP1 may play a role in regulating the proton-motive force in northern, but not southern, killifish in response to thermal acclimation. These data demonstrate the potential for adaptive variation in mitochondrial plasticity in response to cold.

Mitochondrial genotype and phenotypic plasticity of gene expression in response to cold acclimation in killifish.

Adjustments of aerobic metabolic processes are critical components of organismal responses to environmental change that require tight coordination between the nuclear and mitochondrial genomes. Intraspecific differences in mitochondrial genotype can affect gene transcription in both genomes. Thus, variation in mitochondrial genotype may be associated with differences in the plasticity of gene expression when organisms are faced with changes in environmental conditions. Cold acclimation is known to result in metabolic responses involving increases in mitochondrial amount and capacity, suggesting that low temperatures may pose a particular challenge when coordinating the functions of the nuclear and mitochondrial genomes. In this study, we utilized RNA-seq to assess transcriptome-wide gene expression in the muscle of Atlantic killifish (Fundulus heteroclitus) from a population that contains segregating variation in mitochondrial genotype. We examined gene expression plasticity in response to 5 °C acclimation and the effects of mitochondrial genotype on this plasticity. Cold acclimation resulted in changes in gene expression consistent with up-regulation of genes involved in many cellular functions, including spliceosomal and proteasomal processes, and with down-regulation of genes involved in extracellular matrix, muscle contraction and oxidative phosphorylation functions. There were few differences in gene expression between killifish with different mitochondrial genotypes: 14 genes demonstrated significant interactions between mitochondrial genotype and acclimation temperature and three genes demonstrated effects of mitochondrial genotype alone. These results indicate that variation in mitochondrial genotype has modest effects on gene expression; the majority of which are revealed as differences in plasticity as a result of environmental change.

Thermal acclimation and subspecies-specific effects on heart and brain mitochondrial performance in a eurythermal teleost (Fundulus heteroclitus).

Mitochondrial performance may play a role in setting whole-animal thermal tolerance limits and their plasticity, but the relative roles of adjustments in mitochondrial performance across different highly aerobic tissues remain poorly understood. We compared heart and brain mitochondrial responses to acute thermal challenges and to thermal acclimation using high-resolution respirometry in two locally adapted subspecies of Atlantic killifish (Fundulus heteroclitus). We predicted that 5°C acclimation would result in compensatory increases in mitochondrial performance, while 33°C acclimation would cause suppression of mitochondrial function to minimize the effects of high temperature on mitochondrial metabolism. In contrast, acclimation to both 33 and 5°C decreased mitochondrial performance compared with fish acclimated to 15°C. These adjustments could represent an energetic cost-saving mechanism at temperature extremes. Acclimation responses were similar in both heart and brain; however, this effect was smaller in the heart, which might indicate its importance in maintaining whole-animal thermal performance. Alternatively, larger acclimation effects in the brain might indicate greater thermal sensitivity compared with the heart. We detected only modest differences between subspecies that were dependent on the tissue assayed. These data demonstrate extensive plasticity in mitochondrial performance following thermal acclimation in killifish, and indicate that the extent of these responses differs between tissues, highlighting the importance and complexity of mitochondrial regulation in thermal acclimation in eurytherms.

The Sedentary Time and Activity Reporting Questionnaire (STAR-Q): reliability and validity against doubly labeled water and 7-day activity diaries.

We determined measurement properties of the Sedentary Time and Activity Reporting Questionnaire (STAR-Q), which was designed to estimate past-month activity energy expenditure (AEE). STAR-Q validity and reliability were assessed in 102 adults in Alberta, Canada (2009-2011), who completed 14-day doubly labeled water (DLW) protocols, 7-day activity diaries on day 15, and the STAR-Q on day 14 and again at 3 and 6 months. Three-month reliability was substantial for total energy expenditure (TEE) and AEE (intraclass correlation coefficients of 0.84 and 0.73, respectively), while 6-month reliability was moderate. STAR-Q-derived TEE and AEE were moderately correlated with DLW estimates (Spearman's ρs of 0.53 and 0.40, respectively; P < 0.001), and on average, the STAR-Q overestimated TEE and AEE (median differences were 367 kcal/day and 293 kcal/day, respectively). Body mass index-, age-, sex-, and season-adjusted concordance correlation coefficients (CCCs) were 0.24 (95% confidence interval (CI): 0.07, 0.36) and 0.21 (95% CI: 0.11, 0.32) for STAR-Q-derived versus DLW-derived TEE and AEE, respectively. Agreement between the diaries and STAR-Q (metabolic equivalent-hours/day) was strongest for occupational sedentary time (adjusted CCC = 0.76, 95% CI: 0.64, 0.85) and overall strenuous activity (adjusted CCC = 0.64, 95% CI: 0.49, 0.76). The STAR-Q demonstrated substantial validity for estimating occupational sedentary time and strenuous activity and fair validity for ranking individuals by AEE.

Quality indicators for ductal carcinoma in situ (DCIS) of the breast: development using a multidisciplinary delphi process and its use in monitoring population-based treatment.

BACKGROUND AND OBJECTIVES: Evaluation of the management of DCIS poses challenges, as standard breast cancer outcome measures such as mortality do not apply. We have developed quality indicators (QIs) to measure the quality of DCIS treatment in Alberta, Canada. METHODS: A modified Delphi process was used to determine QIs in the treatment of DCIS after review of evidence-based clinical practice guidelines. Patients diagnosed with DCIS from 2000 to 2001 (cohort 1) and 2009-2010 (cohort 2) were identified from the Alberta Cancer Registry and QIs were retrospectively abstracted. RESULTS: The expert panel developed eight QIs to assess the overall quality of care for DCIS patients. Five hundred eighty eligible patients were identified in the two cohorts. There was significant improvement in radiation oncology referral, radiation post lumpectomy and complete pathology reporting. Axillary staging significantly increased from 20% (axillary dissection in cohort 1) to 60% (sentinel node biopsy in cohort 2). Other QIs did not differ significantly. CONCLUSIONS: By developing QIs, performance measures for DCIS may assessed and compared over time. Although there have been significant improvements with pathology reporting and radiation oncology assessment and treatment, axillary staging rates are unexpectedly high, necessitating further investigation.

Incidence trends in head and neck cancers and human papillomavirus (HPV)-associated oropharyngeal cancer in Canada, 1992-2009.

PURPOSE: Recently, human papillomavirus (HPV) infection has been causally associated with a subset of head and neck cancers, particularly oropharyngeal cancer. As national cancer reporting systems typically report incidence rates of oropharyngeal cancer grouped with other cancers of the head and neck region, the objective of this study was to present age-standardized incidence trends in oropharyngeal cancer Canada-wide. METHODS: Data were obtained from the Canadian Cancer Registry for cases diagnosed between 1992 and 2009. Trends in age-standardized incidence rates were described for head and neck cancers overall and for HPV-associated oropharyngeal cancer using Joinpoint regression. RESULTS: The age-standardized incidence of head and neck cancers declined significantly in Canada from 1992 to 1998 (annual percentage change [APC] = -3.0, p < 0.01), then remained stable through to 2009. In contrast, the age-standardized incidence of HPV-associated oropharyngeal cancer increased significantly during the same time period, from 1.6 per 100,000 in 1992 to 2.6 in 2009 (APC = 2.7, p < 0.001). The increase in HPV-associated oropharyngeal cancer was greater in males than in females and increased significantly in all age groups, particularly those aged 50-59 (APC = 5.4, p < 0.001). The age-standardized incidence rate of head and neck cancer overall was stable or declined in all age groups except those aged 50-59 where incidence decreased from 1992 to 1997, then increased through to 2009. CONCLUSIONS: The incidence patterns of HPV-associated oropharyngeal cancer and head and neck cancer overall show contrasting trends. Findings highlight the need to surveil HPV-associated oropharyngeal cancer separately from other cancers of the head and neck region in order to monitor these emerging trends.

Opportunistic salpingectomy between 2011 and 2016: a descriptive analysis.

BACKGROUND: Opportunistic salpingectomy (OS) is the removal of fallopian tubes during hysterectomy for benign indications or instead of tubal ligation, for the purpose of preventing ovarian cancer. We determined rates of OS at the time of hysterectomy and tubal sterilization and examined how they changed over the study period. METHODS: Using data from the Canadian Institute for Health Information's Discharge Abstract Database and National Ambulatory Care Reporting System for all Canadian provinces and territories (except Quebec) between the fiscal years 2011 and 2016, we conducted a descriptive analysis of all patients aged 15 years or older who underwent hysterectomy or tubal sterilization. We excluded those with diagnostic codes for any gynecologic cancer and those who underwent unilateral salpingectomy. We examined the proportion who had OS during their hysterectomy and compared the proportion of tubal sterilizations that were OS with the proportion that were tubal ligations. RESULTS: A total of 318 528 participants were included in the study (mean age 42.5 yr). The proportion of hysterectomies that included OS increased from 15.4% in 2011 to 35.5% by 2016. With respect to tubal sterilization, the rate of OS increased from 6.5% of all tubal sterilizations in 2011 to 22.0% in 2016. There was considerable variation across jurisdictions in 2016, with British Columbia having the highest rates (53.2% of all hysterectomies and 74.0% of tubal sterilizations involved OS). INTERPRETATION: The rates of OS increased between 2011 and 2016, but there was considerable variation across the included jurisdictions. Our study indicates room for rates of OS to increase across many of the included jurisdictions.

Population-Based Cancer Survival in Canada and the United States by Socioeconomic Status: Findings from the CONCORD-2 Study.

Background: Population-based cancer survival provides insight into the effectiveness of health systems to care for all residents with cancer, including those in marginalized groups. Methods: Using CONCORD-2 data, we estimated 5-year net survival among patients diagnosed 2004-2009 with one of 10 common cancers, and children diagnosed with acute lymphoblastic leukemia (ALL), by socioeconomic status (SES) quintile, age (0-14, 15-64, ≥65 years), and country (Canada or United States). Results: In the lowest SES quintile, survival was higher among younger Canadian adults diagnosed with liver (23% vs 15%) and cervical (78% vs 68%) cancers and with leukemia (62% vs 56%), including children diagnosed with ALL (92% vs 86%); and higher among older Americans diagnosed with colon (62% vs 56%), female breast (87% vs 80%), and prostate (97% vs 85%) cancers. In the highest SES quintile, survival was higher among younger Americans diagnosed with stomach cancer (33% vs 27%) and younger Canadians diagnosed with liver cancer (31% vs 23%); and higher among older Americans diagnosed with stomach (27% vs 22%) and prostate (99% vs 92%) cancers. Conclusions: Among younger Canadian cancer patients in the lowest SES group, greater access to health care may have resulted in higher cancer survival, while higher screening prevalence and access to health insurance (Medicare) among older Americans during the period of this study may have resulted in higher survival for some screen-detected cancers. Higher survival in the highest SES group for stomach and liver may relate to treatment differences. Survival differences by age and SES between Canada and the United States may help inform cancer control strategies.

Associations of overall and abdominal adiposity with area and volumetric mammographic measures among postmenopausal women.

Whereas mammographic density and adiposity are positively associated with postmenopausal breast cancer risk, they are inversely associated with one another. To examine the association between these two risk factors, a secondary analysis of data from a randomized controlled trial of a year-long aerobic exercise intervention was done. Participants were 302 postmenopausal women aged 50-74 years. Dense fibroglandular and nondense fatty tissue were measured from mammograms using computer-assisted thresholding software for area measurements and a technique relying on the calibration of mammography machines with a tissue-equivalent phantom for volumetric measurements. Adiposity was measured by anthropometry (body mass index, waist circumference), whole-body dual x-ray absorptiometry scans (body fat) and computed tomography scans (abdominal adiposity). Correlations were estimated between and within women, the latter representing the association between the 1-year change in adiposity and mammographic measures. Adiposity was correlated with nondense area and volume (0.50 ≤ r ≤ 0.66 between women; 0.18 ≤ r ≤ 0.46 within women). Between women, adiposity was correlated with dense area and volume (-0.12 ≤ r ≤ -0.30) and with percent dense area and volume (-0.28 ≤ r ≤ -0.48). Because measurements made with scans explained at most only 3% more of the variation in absolute or percent density beyond that explained by anthropometric measurements, anthropometric measurements are likely sufficient for adjustment of the association between mammographic density and breast cancer risk. Adiposity is associated with breast fatty tissue and possibly weakly inversely associated with fibroglandular tissue.

Impact of age-specific recommendation changes on organized breast screening programs.

BACKGROUND: Recent changes in recommendations for mammography screening for women in their forties could have an impact on organized screening programs, as these require clear definition of target and eligible populations. CURRENT STATUS: Internationally, a majority of programs target women fifty and over, and so the recent USPSTF age recommendations for screening are quite consistent with this practice. However, there is a good deal of variability in the availability of population-based screening programs to women in their forties should they choose to participate. FUTURE IMPACT: Several programs are reviewing recommendations regarding the eligibility of women in their forties; as guidelines indicate women in this age group should be eligible for screening, even if not targeted, there is discussion as to whether they should be allowed in programs so that they benefit from the same programmatic quality assurance afforded to the target population of women over 50. Clear communication of the evidentiary basis for the eligibility criteria and target populations is required, so that the public is aware that programs are designed to deliver maximal population impact, while minimizing population risk.

Plasma osmolality reference values in African grey parrots (Psittacus erithacus erithacus), Hispaniolan Amazon parrots (Amazona ventralis), and red-fronted macaws (Ara rubrogenys).

Birds are routinely presented to veterinarians for dehydration. Success with these cases ultimately depends on providing replacement fluids and re-establishing fluid homeostasis. Few studies have been done to determine reference ranges for plasma osmolality in birds. The goals of this study were to determine reference values for plasma osmolality in 3 species of parrots and to provide recommendations on fluid selection for replacement therapy in these species. Blood samples were collected from 21 adult Hispaniolan Amazon parrots (Amazona ventralis), 21 Congo African grey parrots (Psittacus erithacus erithacus), and 9 red-fronted macaws (Ara rubrogenys), and were placed into lithium heparin containers. Plasma osmolality was measured in duplicate with a freezing point depression osmometer. Summary statistics were computed from the average values. Reference ranges, calculated by using the robust method, were 288-324, 308-345, and 223-369 mOsm/kg in African grey parrots, Hispaniolan Amazon parrots, and red-fronted macaws, respectively. The mean +/- SD values were 306 +/- 7, 327 +/- 7, and 304 +/- 18 mOsm/kg in African grey parrots, Hispaniolan Amazon parrots, and red-fronted macaws, respectively. Comparisons with osmolality values in mammals and values previously reported for psittacine bird species suggest that plasma osmolality is slightly higher in parrots than in mammals, species-specific differences exist, and differences between reported values occur. Overall, fluids with an osmolarity close to 300-320 mOsm/L, such as Normosol-R, Plasmalyte-R, Plasmalyte-A, and NaCl 0.9%, can be recommended in parrots for fluid replacement therapy when isotonic fluids are required.

Survival of metastatic colorectal cancer patients treated with chemotherapy in Alberta (1995-2004).

GOALS OF WORK: Clinical trials have suggested that advances in chemotherapy significantly improve the survival of patients with metastatic colorectal cancer. Comparable evidence from clinical practice is scarce. This study aims to investigate the survival of patients with metastatic colorectal cancer treated with chemotherapy in Alberta, Canada. PATIENTS AND METHODS: Trends of relative survival of patients diagnosed in 1994-2003 were assessed using Alberta Cancer Registry (ACR) data. The median overall survival (OS) of patients diagnosed in 2004 was determined by linking Cancer Registry data with Electronic Medical Records (EMR). Cox regression models were fitted to calculate the hazard ratio for patients treated with chemotherapy. RESULTS: The 2-year relative survival for patients with metastatic colorectal cancer who received chemotherapy increased significantly from 29% to 41% over the 10 years (1994-2003, p < 0.015). A 69% reduction in the risk of mortality was observed in the 168 patients who received chemotherapy compared to the 87 patients who did not, after adjusting for age, gender, and number of metastases. The median OS of patients who received chemotherapy was 17.5 months. This is comparable to the 18-20 months seen in recently published clinical trials, considering the patients in this study were from the real clinical practice, nearly half of them were older than 70, and many of them might have important co-morbidities. CONCLUSIONS: The survival of patients diagnosed with metastatic colorectal cancer in Alberta has improved in recent years; this is most likely attributable in large part to the use of chemotherapy.

Prevalence, trend, and sociodemographic association of five modifiable lifestyle risk factors for cancer in Alberta and Canada.

OBJECTIVES: To examine the 12-year trend, in Alberta and Canada, of five modifiable lifestyle risk factors for cancer, and their associations with sociodemographic factors. METHODS: Six surveys collected data from Canadians aged > or =12 years. The prevalence, trends, and sociodemographic association of five lifestyle risk factors (smoking, inactivity, excessive drinking, overweight/obesity, and insufficient fruit/vegetable intake) were examined. RESULTS: Smoking and inactivity decreased significantly: by 5.4% and 2.7% (Alberta men) and 4.9% and 12.1% (Alberta women); by 7.5% and 8.5% (Canada men) and 7.7% and 11.9% (Canada women). Excessive drinking increased significantly: by 3.6% (men) and 0.9% (women), Alberta; by 2.5% (men) and 0.9% (women), Canada. Overweight/obesity significantly increased by 6.0% (Alberta) and 4.1% (Canada) in women. Being female, single, highly educated, or having higher income decreased the likelihood of exposure to multiple lifestyle risk factors; being middle aged, widowed/separated/divorced, or in poor health condition increased the likelihood. CONCLUSIONS: The downward trends for smoking and physical inactivity were in a direction that may help reduce cancer burden. The excessive drinking and overweight/obesity trends did not change in desired direction and deserve attention. The clustering of the lifestyle risk factors in specific social groups provides useful information for future intervention planning.