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Background: We report our experience of selecting tag SNPs in 35 genes involved in iron metabolism in a cohort study seeking to discover genetic modifiers of hereditary hemochromatosis. Methods: We combined our own and publicly available resequencing data with HapMap to maximise our coverage to select 384 SNPs in candidate genes suitable for typing on the Illumina platform. Results: Validation/ design scores above 0.6 were not strongly correlated with SNP performance as estimated by Gentrain score. We contrasted results from two tag SNP selection algorithms, LDselect and Tagger. Varying r(2) from 0.5 to 1.0 produced a near linear correlation with the number of tag SNPs required. We examined the pattern of linkage disequilibrium of three levels of resequencing coverage for the transferrin gene and found HapMap phase 1 tag SNPs capture 45% of the >= 3% MAF SNPs found in SeattleSNPs where there is nearly complete resequencing. Resequencing can reveal adjacent SNPs ( within 60 bp) which may affect assay performance. We report the number of SNPs present within the region of six of our larger candidate genes, for different versions of stock genotyping assays. Conclusion: A candidate gene approach should seek to maximise coverage, and this can be improved by adding to HapMap data any available sequencing data. Tag SNP software must be fast and flexible to data changes, since tag SNP selection involves iteration as investigators seek to satisfy the competing demands of coverage within and between populations, and typability on the technology platform chosen.

Objectives: Previously, based on 6 months of follow-up, we showed that HPV self-sampling improved participation in cervical screening compared to a reminder letter for Pap testing for never- and under-screened women. Here, we report follow-up and related screening outcomes for women who participated in the initial self-sampling over two screening rounds. Setting: The randomised controlled trial was conducted in Australia. Methods: Never- and under-screened women were randomly allocated to the HPV self-sampling or the reminder for Pap test arm and followed at 6 and 36 months since the kits were first mailed. Results: The first round of HPV self-sampling kits were mailed from May–July 2014 to 12 572 women. After 36 months, 19% of never-screened and 9% of under-screened women returned a kit for HPV testing; 2.7% were HPV 16/18 and 5.8% non-16/18 HPV positive. Compliance with first round follow-up was 84% (95% CI: 77.1–89.5%). Non-compliant and cytology triage negative women were mailed another kit at 12 months. Compliance at 12-month follow-up was 59.3% (49.4 to 68.6%). Of 37 women with a 12-month repeat HPV, 70% were positive. Of women who tested negative for HPV in the first round (n = 1573), 25% attended regular screening in the next round and none had CIN2 + detected. The overall prevalence of CIN2 + was 8.5 per 1000 screened (4.8 to 13.9 per 1000). Conclusion: While self-sampling can successfully engage women, compliance with repeat testing may require monitoring. The clinician-supported self-collection pathway now in use in Australia will likely improve women's engagement with follow-up. [ABSTRACT FROM AUTHOR]

The prevalence of iron-overload-related disease for C282Y homozygotes is examined. Findings reveal the development of iron-overload-related disease in a substantial proportion of men due to elevated levels of serum ferritin and transferrin saturation.

Hereditary haemochromatosis (HH) is an inherited disorder of iron absorption. It meets several of the key public health principles for population-based screening and is considered to be a test-case for public health genetics. However, there has been relatively little debate in the public health or wider community regarding the merits of population-based genetic screening for HH. Genetic susceptibility to HH occurs in about 1:200 people and although mortality is low (age-standardised rate 2.75/million), there are potentially serious clinical manifestations of iron overload. Regular venesection is a simple and effective treatment for early stage iron overload. DNA-based testing is available and iron overload may be identified using serum transferrin saturation and ferritin tests. However, there are important gaps in knowledge relevant to screening for HH. The limited data on penetrance of HFE genotypes, and thus the uncertain probability that genetically susceptible individuals will develop clinically significant disease, is a major impediment to population-based genetic screening. Clinical evidence supports treating early-stage disease but no randomised controlled trials of the effectiveness of screening in reducing the burden of disease have been conducted. In addition, the natural history of early stages of HH and factors that may modify progression are unclear. Two international consensus panels on HH concluded that there is insufficient evidence for population-based screening at present. We present recommendations to advance the debate on screening for HH in Australia.

Objectives. The purpose of this study was to describe the establishment of a national surveillance system for newly acquired human immunodeficiency virus (HIV) infection and present the first 3 years' results. Methods. All new cases of diagnosed HIV infection were reported to the national HIV surveillance center through state and territory health authorities. Information sought on each case included evidence of whether the infection had been newly acquired, defined by the diagnosis of HIV seroconversion illness or by the report of a negative or indeterminate HIV antibody test result occurring within the 12 months prior to diagnosis of infection. Results. Of 3602 reported cases of HIV infection in adults and adolescents newly diagnosed in Australia between 1991 and 1993,11.4% were identified as newly acquired. The majority (85%) of cases of newly diagnosed HIV infection occurred among men who reported homosexual contact, and 15% of these cases were identified as newly acquired. Average age at diagnosis was 31 years for cases of newly acquired infection and 34 years for other cases. Conclusions. Surveillance for newly acquired HIV infection has been established at a national level in Australia and provides valuable information for planning primary HIV prevention programs. (Am J Public Health. 1994;84:1923-1928), National surveillance data on newly acquired HIV infections in Australia appear to indicate a significant increase in the number of cases contracted between 1991 and 1993. Each health authority in Australia is required to report cases of HIV infection to the national HIV surveillance center. Data suggest there were 410 (11.4%) newly acquired HIV cases among a total of 3602 new infections reported between 1991 and 1993. Most of the cases involved men who were an average of 31 years of age and had homosexual contacts. The marked increase in new infections, from 131 in 1991 to 327 in 1993, may be due to higher reporting accuracy or reflect actual prevalence changes. The relatively low incidence of HIV infection linked to heterosexual activity and intravenous drug use is consistent with previous prevalence data in Australia.

Abstract Background We report our experience of selecting tag SNPs in 35 genes involved in iron metabolism in a cohort study seeking to discover genetic modifiers of hereditary hemochromatosis. Methods We combined our own and publicly available resequencing data with HapMap to maximise our coverage to select 384 SNPs in candidate genes suitable for typing on the Illumina platform. Results Validation/design scores above 0.6 were not strongly correlated with SNP performance as estimated by Gentrain score. We contrasted results from two tag SNP selection algorithms, LDselect and Tagger. Varying r2 from 0.5 to 1.0 produced a near linear correlation with the number of tag SNPs required. We examined the pattern of linkage disequilibrium of three levels of resequencing coverage for the transferrin gene and found HapMap phase 1 tag SNPs capture 45% of the ≥ 3% MAF SNPs found in SeattleSNPs where there is nearly complete resequencing. Resequencing can reveal adjacent SNPs (within 60 bp) which may affect assay performance. We report the number of SNPs present within the region of six of our larger candidate genes, for different versions of stock genotyping assays. Conclusion A candidate gene approach should seek to maximise coverage, and this can be improved by adding to HapMap data any available sequencing data. Tag SNP software must be fast and flexible to data changes, since tag SNP selection involves iteration as investigators seek to satisfy the competing demands of coverage within and between populations, and typability on the technology platform chosen.

Indigenous Australian women have much higher incidence of cervical cancer compared to non-Indigenous women. Despite an organised cervical screening program introduced 25 years ago, a paucity of Indigenous-identified data in Pap Smear Registers remains. Prevalence of cervical abnormalities detected among the screened Indigenous population has not previously been reported. We conducted a retrospective cohort study of population-based linked health records for 1,334,795 female Queensland residents aged 20–69 years who had one or more Pap smears during 2000–2011; from linked hospital records 23,483 were identified as Indigenous. Prevalence was calculated separately for Indigenous and non-Indigenous women, for cytology-detected low-grade (cLGA) and high-grade abnormalities (cHGA), and histologically confirmed high-grade abnormalities (hHGA). Odds ratios (OR) were estimated from logistic regression analysis. In 2010–2011 the prevalence of hHGA among Indigenous women (16.6 per 1000 women screened, 95% confidence interval [CI] 14.6–18.9) was twice that of non-Indigenous women (7.5 per 1000 women screened, CI 7.3–7.7). Adjusted for age, area-level disadvantage and place of residence, Indigenous women had higher prevalence of cLGA (OR 1.4, CI 1.3–1.4), cHGA (OR 2.2, CI 2.1–2.3) and hHGA (OR 2.0, CI 1.9–2.1). Our findings show that Indigenous women recorded on the Pap Smear Register have much higher prevalence for cLGA, cHGA and hHGA compared to non-Indigenous women. The renewed cervical screening program, to be implemented in 2017, offers opportunities to reduce the burden of abnormalities and invasive cancer among Indigenous women and address long-standing data deficiencies. [ABSTRACT FROM AUTHOR]

Background: Increasing cervical screening coverage by reaching inadequately screened groups is essential for improving the effectiveness of cervical screening programs. Offering HPV self-sampling to women who are never or under-screened can improve screening participation, however participation varies widely between settings. Information on women's experience with self-sampling and preferences for future self-sampling screening is essential for programs to optimize participation.Methods: The survey was conducted as part of a larger trial ("iPap") investigating the effect of HPV self-sampling on participation of never and under-screened women in Victoria, Australia. Questionnaires were mailed to a) most women who participated in the self-sampling to document their experience with and preference for self-sampling in future, and b) a sample of the women who did not participate asking reasons for non-participation and suggestions for enabling participation. Reasons for not having a previous Pap test were also explored.Results: About half the women who collected a self sample for the iPap trial returned the subsequent questionnaire (746/1521). Common reasons for not having cervical screening were that having Pap test performed by a doctor was embarrassing (18 %), not having the time (14 %), or that a Pap test was painful and uncomfortable (11 %). Most (94 %) found the home-based self-sampling less embarrassing, less uncomfortable (90 %) and more convenient (98%) compared with their last Pap test experience (if they had one); however, many were unsure about the test accuracy (57 %). Women who self-sampled thought the instructions were clear (98 %), it was easy to use the swab (95 %), and were generally confident that they did the test correctly (81 %). Most preferred to take the self-sample at home in the future (88 %) because it was simple and did not require a doctor's appointment. Few women (126/1946, 7 %) who did not return a self-sample in the iPap trial returned the questionnaire. Their main reason for not screening was having had a hysterectomy.Conclusions: Home-based self-sampling can overcome emotional and practical barriers to Pap test and increase participation in cervical screening despite some women's concerns about test accuracy. Mailing to eligible women and assuring women about test accuracy could further optimize participation in screening. [ABSTRACT FROM AUTHOR]

Unlabelled: Background The study evaluated acceptability, invitation letters and the test kit for a trial of human papillomavirus (HPV) self-sampling among never- and under-screened women in Australia.Methods: Victorian women, 30-69 years, who had never had a Pap test or were overdue for one, participated. Four focus groups including eight to nine participants segmented by age (30-49 and 50-69 years) and screening history (never- and under-screened) were conducted in August 2013. Discussions were recorded and transcribed verbatim and data analysed using thematic content analysis.Results: The response to the concept of HPV self-sampling was positive. Decision-making was largely influenced by the content of a pre-invitation letter. Appealing features of self-sampling were cost (free), convenience (home-based) and anticipated less discomfort (with a swab) than a Pap test. Small kits that fit in mailboxes were preferred over post office parcel collection. The perceived barriers include concerns about test accuracy and lack of confidence that a home-based test would give the same results as a physician administered test. Women wanted information on the timing of receipt of the results and information about the organisation providing the test.Conclusion: HPV self-sampling is a possible alternative for Australian women who are reluctant to have a Pap test and may increase the likelihood of participation in cervical cancer screening if women's concerns about it can be addressed. The findings of this study are relevant for researchers, policymakers and practitioners implementing self-sampling for under-screened women as part of cervical screening programs. [ABSTRACT FROM AUTHOR]

Ductal carcinoma in situ (DCIS) lesions are non-invasive tumours of the breast that are thought to precede most invasive breast cancers (IBCs). As individual DCIS lesions are initiated, grow and invade (i.e. become IBC), the size distribution of the DCIS lesions present in a given human population will evolve. We derive a differential equation governing this evolution and show, for given assumptions about growth and invasion, that there is a unique distribution which does not vary with time. Further, we show that any initial distribution converges to this stationary distribution exponentially quickly. Therefore, it is reasonable to assume that the stationary distribution governs the size of DCIS lesions in human populations which are relatively stable with respect to the determinants of breast cancer. Based on this assumption and the size data of 110 DCIS lesions detected in a mammographic screening programme between 1993 and 2000, we produce maximum likelihood estimates for certain growth and invasion parameters. Assuming that DCIS size is proportional to a positive power p of the time since tumour initiation, we estimate p to be 0.50 with a 95% confidence interval of (0.35, 0.71). Therefore, we estimate that DCIS lesions follow a square-root growth law and hence that they grow rapidly when small and relatively slowly when large. Our approach and results should be useful for other mathematical studies of cancer, especially those investigating biological mechanisms of invasion. [ABSTRACT FROM AUTHOR]

The article presents a study on the comparison between cervical screening rates for women vaccinated with a quadrivalent human papillomavirus (HPV) vaccine and unvaccinated women. Topics discussed include National HPV Vaccination Program Register and Victorian Cervical Cytology Registry data on 20-29-year-old women in Victoria, Australia, screening participation rates for vaccinated and unvaccinated women, and the lower rate of screening among vaccinated women as compared to unvaccinated women.

Background: Organized screening based on Pap tests has substantially reduced deaths from cervical cancer in many countries, including Australia. However, the impact of the program depends upon the degree to which women participate. A new method of screening, testing for human papillomavirus (HPV) DNA to detect the virus that causes cervical cancer, has recently become available. Because women can collect their own samples for this test at home, it has the potential to overcome some of the barriers to Pap tests. The iPap trial will evaluate whether mailing an HPV self-sampling kit increases participation by never- and under-screened women within a cervical screening program. Methods/Design: The iPap trial is a parallel randomized controlled, open label, trial. Participants will be Victorian women age 30-69 years, for whom there is either no record on the Victorian Cervical Cytology Registry (VCCR) of a Pap test (never-screened) or the last recorded Pap test was between five to fifteen years ago (under-screened). Enrolment information from the Victorian Electoral Commission will be linked to the VCCR to determine the never-screened women. Variables that will be used for record linkage include full name, address and date of birth. Never- and under-screened women will be randomly allocated to either receive an invitation letter with an HPV self-sampling kit or a reminder letter to attend for a Pap test, which is standard practice for women overdue for a test in Victoria. All resources have been focus group tested. The primary outcome will be the proportion of women who participate, by returning an HPV self-sampling kit for women in the self-sampling arm, and notification of a Pap test result to the Registry for women in the Pap test arm at 3 and 6 months after mailout. The most important secondary outcome is the proportion of test-positive women who undergo further investigations at 6 and 12 months after mailout of results. Discussion: The iPap trial will provide strong evidence about whether HPV self-sampling could be used in Australia to improve participation in cervical screening for never-and under-screened women. [ABSTRACT FROM AUTHOR]

Background Australia was one of the first countries to introduce a publicly funded national human papillomavirus (HPV) vaccination program that commenced in April 2007, using the quadrivalent HPV vaccine targeting 12- to 13-year-old girls on an ongoing basis. Two-year catch-up programs were offered to 14- to 17- year-old girls in schools and 18- to 26-year-old women in community-based settings. We present data from the school-based program on population-level vaccine effectiveness against cervical abnormalities in Victoria, Australia. Methods Data for women age-eligible for the HPV vaccination program were linked between the Victorian Cervical Cytology Registry and the National HPV Vaccination Program Register to create a cohort of screening women who were either vaccinated or unvaccinated. Entry into the cohort was 1 April 2007 or at first Pap test for women not already screening. Vaccine effectiveness (VE) and hazard ratios (HR) for cervical abnormalities by vaccination status between 1 April 2007 and 30 December 2011 were calculated using proportional hazards regression. Results The study included 14,085 unvaccinated and 24,871 vaccinated women attending screening who were eligible for vaccination at school, 85.0% of whom had received three doses. Detection rates of histologically confirmed high-grade (HG) cervical abnormalities and high-grade cytology (HGC) were significantly lower for vaccinated women (any dose) (HG 4.8 per 1,000 person-years, HGC 11.9 per 1,000 person-years) compared with unvaccinated women (HG 6.4 per 1,000 person-years, HGC 15.3 per 1,000 person-years) HR 0.72 (95% CI 0.58 to 0.91) and HR 0.75 (95% CI 0.65 to 0.87), respectively. The HR for low-grade (LG) cytological abnormalities was 0.76 (95% CI 0.72 to 0.80). VE adjusted a priori for age at first screening, area level socioeconomic status and remoteness index, for women who were completely vaccinated, was greatest for CIN3+/AIS at 47.5% (95% CI 22.7 to 64.4) and 36.4% (95% CI 9.8 to 55.1) for women who received any dose of vaccine, and was negatively associated with age. For women who received only one or two doses of vaccine, HRs for HG histology were not significantly different from 1.0, although the number of outcomes was small. Conclusion A population-based HPV vaccination program in schools significantly reduced cervical abnormalities for vaccinated women within five years of implementation, with the greatest vaccine effectiveness observed for the youngest women. [ABSTRACT FROM AUTHOR]

Background: The quadrivalent human papillomavirus vaccine has been provided in Australia through the National Human Papillomavirus Vaccination Program since April 2007. National registry data demonstrates good coverage of the vaccine, with 73% of school-aged girls having received all three doses. To evaluate the effectiveness of the program, we propose a two-pronged approach. In one (sub study A), the prevalence of the vaccine-targeted human papillomavirus genotypes in a population cohort is being estimated, and will be analysed in relation to vaccination status, cervical cytology screening status, demographic, social, behavioural, medical and clinical factors. In sub study B, the distribution of human papillomavirus genotypes detected in high grade cervical intraepithelial neoplastic lesions from vaccine eligible women is being assessed.Methods/design: Sub Study A involves the recruitment of 1569 women aged 18-25, residing in Victoria, Australia, through Facebook advertising. Women who are sexually active are being asked to provide a self-collected vaginal swab, collected at home and posted into the study centre, where human papillomavirus DNA detection and genotyping is performed. Participants also complete an online questionnaire regarding sexual history, experience with, knowledge of, and attitudes towards human papillomavirus, the human papillomavirus vaccine, and cervical screening.Sub Study B will involve the collection of 500 cervical biopsies, positively identified as containing high grade cervical intraepithelial neoplastic lesions and/or adenocarcinoma in situ. Five serial sections are being taken from each case: sections 1 and 5 are being assessed to confirm the presence of the high grade cervical intraepithelial neoplastic lesions or adenocarcinoma in situ; human papillomavirus genotyping is performed on sections 2 and 3; single lesions are excised from section 4 using laser capture microdissection to specifically define causality of a human papillomavirus genotyping of each specific lesion.Discussion: Australia is well placed to gain a clear and early insight into the effectiveness of the human papillomavirus vaccine in reducing the prevalence of human papillomavirus infection in young women, and any subsequent reduction in the prevalence of pre-cancerous cervical lesions, specifically high grade cervical intraepithelial neoplasia lesions, particularly of vaccine related types. The findings of a successful population based human papillomavirus program will have wide-reaching translational benefits across the globe. [ABSTRACT FROM AUTHOR]

The article reports on a study conducted from 2006-2007 on women aged 40 years and older, who underwent estrogen therapy during their adolescent years because of their tall stature, to determine a hypothesis that associate estrogen with higher risk to breast cancer. The dense area in the breasts of the treated and untreated women are compared. The results suggest that estrogen did have an effect on size and denseness of the breast, although puberty is accelerated in the treated women.

Rates of large breast cancers should decrease in a population that is offered mammography screening, but women continue to present with them. We sought an explanation in a population-based epidemiological study of 1,459 women diagnosed with invasive breast cancer in 2002-2003 in Australia; breast cancers were ≥2 cm in 766 women (53%) and 11-1.9 cm in a comparison group (693, 47%). We interviewed the women about their personal, mammogram and breast histories in the years before diagnosis and collected biological characteristics of tumors and mammogram dates from medical records. The strongest correlate of breast cancer size at diagnosis was the method of detection: the odds of a ≥2 cm breast cancer was substantially lower for detection by a screening mammogram (OR = 0.27, 95% CI 0.21-0.34; p < 0.001) than for detection after a breast symptom. Higher BMI (ORs ∼1.6 for ≥25 kg/m [ABSTRACT FROM AUTHOR]

The article presents a study about the mammographic screening performance for women with risk of breast cancer in Australia. The effects of breast density, age, and hormone therapy use were examined using logistic regression analysis. Results showed that the risk of small screen-detected cancer was associated with age but not with density. Moreover, the risk of large screen-detected cancer was associated with age and density and interval cancer risks increased with density but not with age.