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BackgroundChemotherapy is increasingly used as primary treatment for group D retinoblastoma, whereas primary enucleation is considered to have a diminishing role. This study aimed to compare the management course, including number of examinations under anaesthesia (EUAs), of group D patients treated by enucleation versus chemotherapy.MethodsA retrospective analysis of 92 group D patients, of which 40 (37 unilateral) underwent primary enucleation and 52 (17 unilateral) were treated with intravenous chemotherapy. Number of EUAs was compared between the treatment groups with respect to the whole cohort, using univariate and multivariate analysis, and to unilateral cases only.ResultsPatients were followed up for a median of 61 months (mean: 66, range: 14–156), in which time primary enucleated patients had on average seven EUAs and chemotherapy-treated patients 21 EUAs (p<0.001). Chemotherapy, young age, bilateral disease, multifocal tumours, familial and germline retinoblastoma were found on univariate analysis to correlate with increased number of EUAs (p≤0.019). On multivariate analysis, however, only treatment type and presentation age were found significant (p≤0.001). On subanalysis of the unilateral cases, patients undergoing primary enucleation had in average seven EUAs, as compared with 16 in the chemotherapy group (p<0.001). Of the 55 unilateral-presenting patients, a new tumour developed in the fellow eye only in a single familial case.ConclusionGroup D patients’ families should be counselled regarding the significant difference in number of EUAs following primary enucleation versus chemotherapy when deciding on a treatment strategy. In this regard, primary enucleation would be most beneficial for older patients with unilateral disease.

OBJECTIVES: The role of diet in the etiology of breast cancer is not well understood despite extensive research. In the majority of this work, a single nutrientbased approach has been used which does not take into account combinations of food that are consumed. An alternative to the single nutrient approach is to identify patterns in the dietary intake information and relate these patterns to disease incidence. This investigation characterized dietary patterns among participants of a Canadian case-control study and related these dietary patterns to the incidence of breast cancer.

Maskless optical lithography can improve the economics and performance of multi-patterning by eliminating photomasks and by simplifying the lithography exposure technology. It could also potentially eliminate the need for multi-patterning by enabling dual-wavelength, nonlinear optical recording methods. High-resolution, maskless patterning can be achieved with a scanned-spot-array system in which modulated, diffraction-limited focus spots write the exposure pattern. Each spot has a central zero-intensity interference null along a line parallel to the scan direction for printing sub-resolution line patterns. High throughput can be achieved at the comparatively low repetition rate of excimer lasers (e.g., 6 kHz). The low repetition rate simplifies the optical modulation technology, enabling the use of supplemental modulation controls including dynamic gray-level and beam-centration controls for resolution enhancement.

The “projection operator” method is a variation of the normal-vector method for simulating optical diffraction from biperiodic gratings. A projection operator defined by the normal vector is interpolated over the grating volume rather than interpolating the vector itself. This approach circumvents difficulties associated with sign reversals and discontinuities encountered with the normal-vector method, and it facilitates implementation for general grating geometries. The method is readily extensible to anisotropic and bianisotropic materials. Several numerical examples of the new method are presented, including comparisons to previously published test cases.

There is accumulating evidence that air pollution causes lung cancer. Still, questions remain about exposure misclassification, the components of air pollution responsible, and the histological subtypes of lung cancer that might be produced.

We wished to gain insight into Canadian hospital policy changes between 2000 and 2007 in response to (1) the initial results of the Term Breech Trial suggesting delivery by Caesarean section was preferable for term breech presentation, and (2) the trial’s two-year follow-up and other research and commentary suggesting that risks associated with vaginal breech delivery and delivery by Caesarean section were similar. We also wished to determine the availability of vaginal breech delivery and the feasibility of establishing breech clinics and on-call squads, and whether these could include midwives.

The role of environmental tobacco smoke (ETS) in the causation of lung and breast cancer has been repeatedly evaluated over recent years. In contrast, its impact on the risk of adult leukemia has received little attention.

Abstract Objectives: To evaluate the impact of active smoking, obesity, and dietary intakes on the risk of adult leukemia.

A U.S. analysis suggested a relation between self-reported residential proximity to industrial plants and non-Hodgkin lymphoma (NHL) risk.

The relationship between occupational exposure to magnetic fields and brain cancer in men was investigated using population-based case-control data collected in eight Canadian provinces. Emphasis was placed on examining the variations in risk across different histological types.

To explore the hypothesis that insulin resistance may be an etiologic factor in pancreatic cancer, we assessed the pancreatic cancer risk associated with anthropometric factors and physical activity, both of which are important determinants of insulin sensitivity in humans. Three hundred and twelve patients with histologically confirmed pancreatic cancer were compared to 2,919 controls in a population-based, case-control study in 7 of the 10 Canadian provinces. Participants were asked to report their exposure status for the period 2 years before interview. Men in the highest quartile of body mass index (BMI, ≥28.3 kg/m²) were at increased risk of pancreatic cancer [adjusted odds ratio (OR) = 1.90, 95% confidence interval (CI) 1.08–3.35]. In addition, men who reported a decrease in weight of at least 2.9% from their lifetime maximum were at reduced risk compared to those reporting a ≤2.9% loss (≥10.2% loss, OR = 0.51, 95% CI 0.30–0.86). BMI 2 years before interview was not associated with pancreatic cancer risk among women, though those reporting a ≥12.5% decrease in weight from their lifetime maximum had substantially lower risk compared to those in the baseline quartile (OR = 0.53, 95% CI 0.29–0.99). After adjustment for age, province of residence, dietary intake and anthropometric factors, men in the highest quartile of the composite moderate and strenuous physical activity index were at reduced risk of pancreatic cancer (OR = 0.53, 95% CI 0.31–0.90). Physical activity did not appear to be associated with pancreatic cancer among women, though a tendency for reduced risk with increasing levels of strenuous activity was suggested (p for trend = 0.06). Our findings support the hypothesis that insulin resistance is an etiologic factor in the development of pancreatic neoplasms among men and possibly women. © 2001 Wiley-Liss, Inc.

Although the risk of lung cancer among never-smokers living with a spouse who smokes has been extensively studied, the impact of lifetime residential and workplace environmental tobacco smoke has received less attention. As part of a large population-based case-control study of lung cancer, we collected lifetime residential and occupational passive smoking information from 71 women with lung cancer and 761 healthy control subjects, all of whom reported being lifetime nonsmokers. The adjusted odds ratio (OR) for lung cancer associated with residential passive exposure only was 1.21 (95% confidence interval [CI] 0.5–2.8). Although more years of and more intense residential passive smoke exposure tended to be associated with higher risk estimates, no clear dose-response relationship was evident. The OR for women with passive exposure as a child and as an adult was 1.63 (95% CI 0.8–3.5) and for those only exposed as an adult 1.20 (95%CI 0.5–3.0). Exposure to environmental tobacco smoke only in the workplace was associated with an adjusted OR of 1.27 (95% CI 0.4–4.0). Risks associated with increasing occupational exposure year tertiles were 1.24, 1.71 and 1.71. Total smoker-years of residential and occupational exposure combined resulted in a statistically significant trend (linear test for trend p = 0.05) with ORs for tertiles of exposure of 0.83, 1.54 and 1.82. Our results are consistent with the literature suggesting that long-term, regular exposure to either residential or occupational environmental tobacco smoke is associated with increased lung cancer risk in never-smoking women. © 2001 Wiley-Liss, Inc.

A case-control study involving interviews with 227 lung-cancer cases and 227 matched hospital controls was conducted in Heilongjiang Province in northeast China to examine the influence of dietary factors on the risk of developing lung cancer. Lung-cancer cases were all incident cases judged to be suitable candidates for tumor removal by surgery. Controls were selected among hospitalized patients with non-neoplastic and non-lung disease. The overall male lung-cancer risks associated with cigarette smoking were similar to those reported in other Chinese studies but quite low compared to risks in Western countries. However, the subjects in this study were relatively young (average age 53.2), had started to smoke on average at a relatively old age (21.3 years), and only smoked an average of 18.7 cigarettes per day. Lung-cancer risk was not strongly associated with any of the nutrients examined, when all cases were compared to all controls. However, the data were suggestive of differences in the relationship of diet to risk among smokers and non-smokers. Cautious interpretation is required because of the wide confidence intervals due to limited sample size. Among the smokers, only higher β-carotene was associated with estimates suggesting a lowered risk. Among non-smokers, the evidence suggested that increased vegetable consumption might reduce risk, consumption of any fruit might reduce risk but β-carotene was unrelated to risk. The differences observed in the relationship of diet to lung-cancer risk between Chinese smokers and non-smokers warrant further study. Int. J. Cancer 71: 924-931, 1997. © 1997 Wiley-Liss Inc.

Several population-based health databases exist in Canada which provide valuable systematic information for facilitating epidemiological evaluation of human health in the Great Lakes Basin. They include the long-established Canadian Mortality Database, a national birth defects registry, a provincial hospitalization database, and provincial and national cancer registry systems. The most recent addition is the National Enhanced Cancer Surveillance System which currently is being implemented to allow for detailed evaluation of air and water quality concerns in relation to a range of cancer types. The system includes statistical evaluation of geographical cancer incidence patterns; development of a national environmental quality database; and systematic collection of individual risk factor information for a large number of newly diagnosed cancer cases and a population control group. A brief description of each database and examples of relevant research using each of these databases is presented.

Summary Mechanical injury to the sapwood of Quercus alba, Robinia pseudoacacia, and Maclura pomifera resulted in the formation of discolored tissue which was more resistant to decay fungi than the adjacent uninjured sapwood but usually less resistant than the heartwood. Considerable tree-to-tree variation in response to injury, as measured by subsequent variations in decay resistance, was noted. The exact cause for this induced decay resistance is unknown, but it appears to be due to fungistatic substances produced in situ by the dying parenchymous cells in the xylem.

ObjectivesTo evaluate whether the stage distribution among women diagnosed as having breast cancer differs between those who have received breast implants for cosmetic purposes and those with no implants and to evaluate whether cosmetic breast augmentation before the detection of breast cancer is a predictor of post-diagnosis survival.DesignSystematic review of observational studies with two meta-analyses.Data sourcesSystematic search of the literature published before September 2012 conducted in Medline, Embase, Global health, CINAHL, IPAB, and PsycINFO.Study selectionEligible publications were those that included women diagnosed as having breast cancer and who had had augmentation mammaplasty for cosmetic purposes.ResultsThe overall odds ratio of the first meta-analysis based on 12 studies was 1.26 (95% confidence interval 0.99 to 1.60; P=0.058; I2=35.6%) for a non-localized stage of breast cancer at diagnosis comparing women with implants who had breast cancer and women without implants who had breast cancer. The second meta-analysis, based on five studies, evaluated the relation between cosmetic breast implantation and survival. This meta-analysis showed reduced survival after breast cancer among women who had implants compared with those who did not (overall hazard ratio for breast cancer specific mortality 1.38, 95% confidence interval 1.08 to 1.75).ConclusionsThe research published to date suggests that cosmetic breast augmentation adversely affects the survival of women who are subsequently diagnosed as having breast cancer. These findings should be interpreted with caution, as some studies included in the meta-analysis on survival did not adjust for potential confounders. Further investigations are warranted regarding diagnosis and prognosis of breast cancer among women with breast implants.

To evaluate the safety of home births in North America involving direct entry midwives, in jurisdictions where the practice is not well integrated into the healthcare system.