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Objectives: According to recent census data, 1,216,600 Canadians are of Chinese descent, and over 80% of Chinese Canadians are foreign born. Approximately 10% of Chinese immigrants are chronic carriers of hepatitis B, compared with less than 0.5% of the general population. English as a second language (ESL) classes provide ready access for individuals with limited English proficiency who are not reached by English language health education materials and media campaigns. We conducted a group-randomized trial to evaluate the effectiveness of a hepatitis B ESL educational curriculum for Chinese immigrants., Methods: Five community-based organizations that provide ESL education in the greater Vancouver area participated in the study. Forty-one ESL classes (which included 325 Chinese students) were randomly assigned to experimental or control status. A follow-up survey, conducted six months after randomization, assessed knowledge about hepatitis B. Generalized estimating equations were used to analyze the data., Results: Follow-up surveys were completed by 298 (92%) of the students. At follow-up, experimental group students were significantly (p < 0.05) more likely than control group students to know that immigrants have higher hepatitis B infection rates than people who were born in Canada; hepatitis B can be spread during childbirth, during sexual intercourse and by sharing razors; hepatitis B is not spread by sharing eating utensils; and hepatitis B infection can cause cirrhosis and liver cancer., Conclusion: Our findings indicate that ESL curricula can have a positive impact on health knowledge among Chinese immigrants with limited English. Future research should evaluate the effectiveness of ESL curricula for other immigrant groups, as well as other health topics.

Breast cancer and cervical cancer are major contributors to morbidity and mortality for the Vietnamese Canadian women. Vietnamese women face multiple barriers to obtaining effective preventive care and treatment for these diseases. This paper reports the influence of socioeconomic factors on Vietnamese Canadian women's breast and cervical cancer screening behaviors. In-depth semistructured interviews were conducted with Vietnamese Canadian women and health care providers. The study revealed that low socioeconomic status is a major barrier to women's participation in breast and cervical cancer screening, despite the fact that health care in Canada is funded publicly by the Medicare system. The Vietnamese Canadian women and health care providers in the present study identified a number of major dimensions through which socioeconomic issues were associated with Vietnamese Canadian women's access to and use of health care for the prevention of breast and cervical cancer, including (a) financial concerns; (b) language, occupational opportunities, and downward mobility; (c) economics and women's households; and (d) low socioeconomic status and screening behaviors. Implications are discussed for increasing Vietnamese Canadian women's utilization of breast and cervical cancer screening services.

We have previously shown that a low-fat dietary intervention for 2 years in women with extensive mammographic density decreased mammographic density to a greater extent than in the control group. Post-hoc analysis indicated that this effect was strongest in women who became postmenopausal during the follow-up period. The purpose of the present study was to determine if this potentially important finding could be confirmed in a new and larger group of subjects with a longer follow-up time. Participants in a low-fat dietary intervention trial who were premenopausal at entry and became postmenopausal during follow-up were examined. Total breast, dense, and non-dense area and percent density were measured in baseline and postmenopause mammograms using a computer-assisted method. Total breast and non dense area increased more in the control group compared to the intervention group (for breast area 2.6 and 0.2 cm(2), respectively; P=0.05, and for non-dense area 10.9 and 8.1 cm(2), respectively; P=0.06). Dense area decreased to a similar degree in both groups (-8.2 and -8.0 cm(2), respectively; P=0.84). Percent density decreased to a slightly greater degree in the control compared to intervention group (-9.4 and -7.8%, respectively, P=0.11). There were no significant differences between study groups after adjustment for weight change. Menopause reduced density to a similar extent in the low-fat diet and control groups. If a low-fat diet reduces breast cancer risk, the effect is unlikely to be through changes in mammographic density at menopause.

Background: Geographical variation and temporal trends in the incidence of esophageal and gastric cancers vary according to both tumour morphology and organ subsite. Both diseases are among the deadliest forms of cancer. The incidence and survival rates for gastric and esophageal carcinoma in British Columbia (BC) between 1990 and 1999 are described., Methods: Incidence data for the period 1990 to 1999 were obtained from the BC Cancer Registry. Age-adjusted incidence and survival rates were computed by anatomical subsite, histological type and sex. All rates were standardized to the 1996 Canadian population. The estimated annual percentage change (EAPC) was used to measure incidence changes over time. Kaplan-Meier curves were used to show survival rates, and log-rank tests were used to test for differences in the curves among various groups., Results: Between 1990 and 1999, 1741 esophageal cancer cases and 3431 gastric cancer cases were registered in BC. There was an increase in the incidence of adenocarcinoma of the esophagus over time (EAPC=9.6%) among men, and of gastric cardia cancer among both women (EAPC=9.2%) and men (EAPC=3.8%). Patients with proximal gastric (cardia) cancer had significantly better survival rates than patients with cancer in the lower one-third of the esophagus. Among gastric cancers, patients with distal tumours had a significantly better survival rate than patients with proximal tumours., Discussion: The incidences of proximal gastric cancer and esophageal adenocarcinoma are increasing, and their survival patterns are different. Examining these cancers together may elucidate new etiological and prognostic factors.

To study the feasibility of self-collected specimens for testing human papillomavirus (HPV) status among hard-to-reach women, outreach nurses recruited women in women's centres, shelters and alleys in Vancouver's Downtown Eastside. Of the 151 participants for whom samples were available, 43 (28.5%) tested positive for high-risk HPV. Outreach nurses were able to recontact 81.4% of the participants who tested positive and referred them for further testing. About 14% (21/151) of participants had never received a Papanicolaou smear in British Columbia, as compared with 8.3% (608/7336) of women in the BC general population (p < 0.05). This difference suggests that self-collection of specimens for HPV testing is a feasible method to reach women who have not previously participated in cervical cancer screening programs.

Background: Greater weight and body mass index (BMI) are negatively correlated with mammographic density, a strong risk factor for breast cancer, and are associated with an increased risk of breast cancer in postmenopausal women, but with a reduced risk in premenopausal women. We have examined the associations of body size and mammographic density on breast cancer risk., Method: We examined the associations of body size and the percentage of mammographic density at baseline with subsequent risk of breast cancer among 1,114 matched case-control pairs identified from three screening programs. The effect of each factor on risk of breast cancer was examined before and after adjustment for the other, using logistic regression., Results: In all subjects, before adjustment for mammographic density, breast cancer risk in the highest quintile of BMI, compared with the lowest, was 1.04 [95% confidence interval (CI), 0.8-1.4]. BMI was associated positively with breast cancer risk in postmenopausal women, and negatively in premenopausal women. After adjustment for density, the risk associated with BMI in all subjects increased to 1.60 (95% CI, 1.2-2.2), and was positive in both menopausal groups. Adjustment for BMI increased breast cancer risk in women with 75% or greater density, compared with 0%, increased from 4.25 (95% CI, 1.6-11.1) to 5.86 (95% CI, 2.2-15.6)., Conclusion: BMI and mammographic density are independent risk factors for breast cancer, and likely to operate through different pathways. The strong negative correlated between them will lead to underestimation of the effects on risk of either pathway if confounding is not controlled.

Background: Some types of hormone therapy increase both risk of breast cancer and mammographic density, a risk factor for the disease, suggesting that mammographic density may be a surrogate marker for the effects of hormones on risk of breast cancer. This research was undertaken to determine whether the effect of hormone therapy on breast cancer risk is mediated by its effect on mammographic density., Methods: Individually matched cases and controls from three nested case-control studies in breast screening populations were studied. Cases had developed invasive breast cancer at least 12 months after the initial screen. Information was collected on hormone use and other risk factors at the time of the baseline mammogram, and percent density was measured by a computer-assisted method., Results: There were 1,748 postmenopausal women, of whom 426 (24.4%) were using hormones at the time of their initial screening mammogram. Current use of hormone therapy was associated with an increased risk of breast cancer (odds ratio, 1.26; 95% confidence interval, 1.0-1.6) that was little changed by adjustment for percent density in the baseline mammogram (odds ratio, 1.19; 95% confidence interval, 0.9-1.5). Percent density in the baseline mammogram was among cases greater in current users of hormones that in never-users (difference = 5.0%, P < 0.001), but the difference was smaller and nonsignificant in controls (difference = 1.6%, P = 0.3)., Conclusion: Although the effects of hormone therapy on mammographic density were greater in cases than controls, we did not find evidence that these effects were causally related to risk of breast cancer.

There is a pressing need for the development of visual aids that will facilitate the detection of oral premalignant lesions (OPLs) with a high-risk of progression. Preliminary data suggest that toluidine blue stain may be preferentially retained by OPLs with high-risk molecular clones. In this study, we monitored OPLs from 100 patients without any history of oral cancer for an average of 44 months in order to evaluate the association of toluidine blue status with clinicopathologic risk factors, molecular patterns (microsatellite analysis on seven chromosome arms: 3p, 9p, 4q, 8p, 11q, 13q, and 17p) and outcome. Toluidine blue-positive staining correlated with clinicopathologic risk factors and high-risk molecular risk patterns. Significantly, a >6-fold elevation in cancer risk was observed for toluidine blue-positive lesions, with positive retention of the dye present in 12 of the 15 lesions that later progressed to cancer (P = 0.0008). This association of toluidine blue status with risk factors and outcome was evident even when the analysis was restricted to OPLs with low-grade or no dysplasia. Our results suggest the potential use of toluidine blue in identifying high-risk OPLs.

Purpose: Translation of cross-cultural surveys and programs pose unique challenges. This paper identifies potential pitfalls of current translation guidelines and presents solutions employed for one project., Methods: We followed current guidelines for translation of survey instruments including forward and back translation, and also utilized qualitative methods to decenter survey questions. In addition, our project adapted translation by committee with a core translation team of bilingual/trilingual investigators and staff members with diverse skills and complementary degrees of proficiency in the languages and dialects of interest., Principal Findings: This approach resulted with a mechanism for emic equivalence, identifying and resolving dialectic and sociolinguistic concerns, selecting appropriate written Chinese styles, and providing appropriate linguistic training to interviewers., Conclusions: An understanding of the history of a people and its ramifications for the language are important components of the translation process. Allocation of appropriate time, resources, and skills are critical to the successful development of valid cross-cultural survey instruments and effective programs.

Study Purpose: Chinese women in North America have high rates of invasive cervical cancer and low levels of Papanicolaou (Pap) testing use. This study examined Pap testing barriers and facilitators among Chinese American women., Basic Procedures: A community-based, in-person survey of Chinese women was conducted in Seattle, Washington during 1999. Four hundred and thirty-two women in the 20-79 years age-group were included in this analysis. The main outcome measures were a history of at least one previous Pap smear and Pap testing within the last 2 years., Main Findings: Nineteen percent of the respondents had never received cervical cancer screening and 36% had not been screened in the previous 2 years. Eight characteristics were independently associated with a history of at least one Pap smear: being married, thinking Pap testing is necessary for sexually inactive women, lack of concerns about embarrassment or cancer being discovered, having received a physician or family recommendation, having obtained family planning services in North America, and having a regular provider. The following characteristics were independently associated with recent screening: thinking Pap testing is necessary for sexually inactive women, lack of concern about embarrassment, having received a physician recommendation, having obtained obstetric services in North America, and having a regular provider., Principal Conclusions: Pap testing levels among the study respondents were well below the National Cancer Institute's Year 2000 goals. The findings suggest that cervical cancer control interventions for Chinese are more likely to be effective if they are multifaceted.

Epidemiological data on most cancer sites suggest that consumption of plant foods, which contain high levels of antioxidants, might slow or prevent the appearance of cancer. We used data from three case-control studies to test this hypothesis. The total study population consisted of 617 incident cases of prostate cancer and 636 population controls from Ontario, Quebec, and British Columbia. Dietary information was collected by an in-person interview with a detailed quantitative dietary history. Unconditional logistic regression analyses were performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). A decreasing, statistically significant association was found with increasing intakes of green vegetables (OR = 0.54, 95% CI = 0.40-0.71 for 4th quartile), tomatoes (OR = 0.64, 95% CI = 0.45-0.91), beans/lentils/nuts (OR = 0.69, 95% CI = 0.53-0.91), and cruciferous vegetables (OR = 0.69, 95% CI = 0.52-0.91 for 3rd quartile). Higher intakes of fruit were associated with higher ORs (OR = 1.51, 95% CI = 1.14-2.01 for 4th quartile), an effect that was seen for total fruit and citrus fruit, as well as for all other noncitrus fruits. Among the grains, refined-grain bread intake was associated with a decrease in risk (OR = 0.65 for 4th quartile), whereas whole-grain breakfast cereals were associated with a higher risk for prostate cancer. Of all the antioxidant nutrients studied, the ORs were higher with higher intakes of cryptoxanthin (OR = 1.44, 95% CI = 1.09-1.89 for 4th quartile). Exposure to certain dietary components of plant origin, which are potentially modifiable, indicates the theoretical scope for reducing the risk from prostate cancer. Future experimental studies or trials are warranted for further understanding.

There are very few large scale studies that have examined the association of prostate cancer with alcohol and other beverages. This relationship was examined in a case-control study conducted in 3 geographical areas of Canada [Metropolitan Toronto (Ontario), Montreal (Quebec), and Vancouver (British Columbia)] with 617 incident cases and 637 population controls. Complete history of beverage intake was assessed by a personal interview with reference to a 1-year period prior to diagnosis or interview. In age- and energy-adjusted models for all centers combined, the odds ratio (OR) for the highest quintile of total alcohol intake was 0.89. For alcoholic beverages separately, it was 0.68 for the highest tertile of beer, 1.12 for wine and 0.86 for liquor. The decreasing trend was significant for beer intake. The results were only significant for British Columbia out of all the 3 centers studied. Whereas coffee and cola intake was not associated with prostate cancer, a decrease in risk was observed with tea intake of more than 500 g per day (OR 0.70). Our results do not support a positive association between total alcohol, coffee and prostate cancer.

The morphologic subgroups of intraductal carcinoma in situ (DCIS) of the breast may be biologically different. Thirty-eight patients with comedo-type DCIS treated with local resection with or without radiotherapy are presented. Thirteen of 35 patients had a family history of breast cancer, with 11 patients having an affected first-degree relative. This is significantly increased over other series of breast cancer patients. Recurrence was ipsilateral in all patients and occurred at the site of the original disease. Recurrence occurred in 4 of 30 patients treated with local resection only and 2 of 8 treated with local resection plus radiotherapy. The length of mean follow-up was 39 months. Because of the paucity of studies, these results cannot be compared with others, but there does appear to be a significant incidence of local recurrence after resection for comedo-type DCIS. Immunohistochemical and oncogene studies as they relate to comedo-type DCIS are discussed.