Cancer incidence in the AGRICAN cohort study (2005–2011)

BackgroundNumerous studies have been conducted among farmers, but very few of them have involved large prospective cohorts, and few have included a significant proportion of women and farm workers. Our aim was to compare cancer incidence in the cohort (overall, by sex, and by work on farm, occupational status and pesticide use) within the general population.MethodsMore than 180,000 participants in the AGRICAN cohort were matched to cancer registries to identify cancer cases diagnosed from enrolment (2005–2007) to 31st December 2011. We calculated standardized incidence ratios (SIRs) and 95% confidence intervals (95%CIs).ResultsOver the period, 11,067 incident cancer cases were identified (7304 men and 3763 women). Overall cancer incidence did not differ between the cohort and the general population. Moreover, SIRs were significantly higher for prostate cancer (SIR = 1.07, 95%CI 1.03–1.11) and non-Hodgkin lymphoma (SIR = 1.09, 95%CI 1.01–1.18) among men, skin melanoma among women (SIR = 1.23, 95%CI 1.05–1.43) and multiple myeloma (men: SIR = 1.38, 95%CI 1.18–1.62; women: SIR = 1.26, 95%CI 1.02–1.54). In contrast, SIRs were lower for upper aerodigestive tract and respiratory cancers. Increase in risk was greater in male farm workers for prostate and lip cancer, in female farm workers for skin melanoma, and in male farm owners for multiple myeloma. Moreover, incidence of multiple myeloma and skin melanoma was higher among male and female pesticide users respectively.ConclusionWe found a decreased incidence for tobacco-related cancers and an increased incidence of prostate cancers, skin melanoma and multiple myeloma. Specific subgroups had a higher cancer incidence related to occupational status and pesticide use.     

Birth weight and subsequent risk of cancer

Background: We aimed to determine the association between self-reported birth weight and incident cancer in the Women's Health Initiative Observational Study cohort, a large multiethnic cohort of postmenopausal women. Methods: 65,850 women reported their birth weight by category (<6 lbs, 6–7 lbs 15 oz, 8–9 lbs 15 oz, and ≥10 lbs). All self-reported, incident cancers were adjudicated by study staff. We used Cox proportional hazards regression to estimate crude and adjusted hazard ratios (aHR) for associations between birth weight and: (1) all cancer sites combined, (2) gynecologic cancers, and (3) several site-specific cancer sites. Results: After adjustments, birth weight was positively associated with the risk of lung cancer (p = 0.01), and colon cancer (p = 0.04). An inverse trend was observed between birth weight and risk for leukemia (p = 0.04). A significant trend was not observed with breast cancer risk (p = 0.67); however, women born weighing ≥10 lbs were less likely to develop breast cancer compared to women born between 6 lbs-7 lbs 15 oz (aHR 0.77, 95% CI 0.63, 0.94). Conclusion: Birth weight category appears to be significantly associated with the risk of any postmenopausal incident cancer, though the direction of the association varies by cancer type.     

Cancer risk and all-cause mortality among Norwegian military United Nations peacekeepers deployed to Kosovo between 1999 and 2011

ObjectiveMedia reports of leukaemia and other cancers among European United Nations (UN) peacekeepers who served in the Balkans, and a scientific finding of excess Hodgkin lymphoma among Italian UN peacekeepers who served in Bosnia, suggested a link between cancer incidence and depleted uranium (DU) exposure. This spurred several studies on cancer risk among UN peacekeepers who served in the Balkans. Although these studies turned out to be negative, the debate about possible cancers and other health risks caused by DU exposure continues. The aim of the present study was to investigate cancer incidence and all-cause mortality in a cohort of 6076 (4.4% women) Norwegian military UN peacekeepers deployed to Kosovo between 1999 and 2011.MethodsThe cohort was followed for cancer incidence and mortality from 1999 to 2011. Standardised incidence ratios for cancer (SIR) and mortality ratios (SMR) were calculated from national rates.ResultsSixty-nine cancer cases and 38 deaths were observed during follow-up. Cancer incidence in the cohort was similar to that in the general Norwegian population. No cancers in the overall cohort significantly exceeded incidence rates in the general Norwegian population, but there was an elevated SIR for melanoma of skin in men of 1.90 (95% confidence interval [CI] 0.95–3.40). A fivefold increased incidence of bladder cancer was observed among men who served in Kosovo for ≥1 year, based on 2 excess cases (SIR = 5.27; 95% CI 1.09–15.4). All-cause mortality was half the expected rate (SMR = 0.49; 95% CI 0.35–0.67).ConclusionOur study did not support the suggestion that UN peacekeeping service in Kosovo is associated with increased cancer risk.     

Risk factors for breast cancer in the breast cancer risk model study of Guam and Saipan

BackgroundChamorro Pacific Islanders in the Mariana Islands have breast cancer incidence rates similar to, but mortality rates higher than, those of U.S. women. As breast cancer risk factors of women of the Mariana Islands may be unique because of ethnic and cultural differences, we studied established and suspected risk factors for breast cancer in this unstudied population.MethodsFrom 2010–2013, we conducted retrospective case-control study of female breast cancer (104 cases and 185 controls) among women in the Mariana Islands. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each of various lifestyle-related factors from logistic regression of breast cancer, in all women and in pre- and postmenopausal women separately. Tests for interaction of risk factors with ethnicity were based on the Wald statistics for cross-product terms.ResultsOf the medical and reproductive factors considered — age at menarche, breastfeeding, number of live births, age at first live birth, hormone use, and menopause — only age at first live birth was confirmed. Age at first live birth, among parous women, was higher among cases (mean 24.9 years) than controls (mean 23.2 years); with increased breast cancer risk (OR = 2.53; 95% CI, 1.04–6.19 for age ≥ 30y compared to <20y, P for trend = 0.01). Of the lifestyle factors —body mass index, waist circumference, physical activity, alcohol and betel-nut intake, and education — only waist circumference (OR = 1.65; 95% CI 0.87–3.14 for the highest tertile group compared to the lowest, P for trend = 0.04) was significantly associated with breast cancer risk and only in Filipino women. The association with many other established risk factors, such as BMI, hormone use and physical activity, were in the expected direction but were not significant. Associations for family history of breast cancer and alcohol intake were not evidentConclusionsThe results provide a basis for cancer prevention guidance for women in the Mariana Islands.     

Mortality and incidence of new primary cancers in men with prostate cancer: A Danish population-based cohort study

Background: Prostate cancer (PC) survivors may have an increased risk of new primary cancers (NPCs) due to shared risk factors or PC-directed treatments. Methods: Using Danish registries, we conducted a cohort study of men with (n = 30,220) and without PC (n = 151,100) (comparators), matched 1:5 on age and PC diagnosis/index date. We computed incidence rates of NPCs per 10,000 person years (PY) and associated 95% confidence intervals (CI), and used Cox proportional hazards regression to compute hazard ratios (HRs) and 95%CI, adjusting for comorbidities. In order to obviate any impact of shorter survival among prostate cancer patients, we censored comparator patients when the matched prostate cancer patient died or was censored. Results: Follow-up spanned 113,487 PY and 462,982 PY in the PC and comparison cohorts, respectively. 65% of the cohorts were aged >70 years at diagnosis. Among PC patients, 51% had distant/unspecified stage, and 63% had surgery as primary treatment. The PC cohort had lower incidence of NPCs than their comparators. The adjusted HR of NPC among men with PC versus the comparators was 0.84 (95%CI = 0.80, 0.88). Lowest HRs were among older men, those with distant stage, and were particularly evident for cancers of the brain, liver, pancreas, respiratory, upper gastrointestinal, and urinary systems. Conclusions: We find no evidence of an increased risk of NPCs among men with PC. The deficit of NPCs among men with PC may be a true effect but is more likely due to lower levels of risk factors (e.g., smoking) in PC patients versus comparators, clinical consideration of cancers at new organs as metastases rather than new primaries, or under-recording/under-reporting of NPCs among PC patients.     

Cancer survival in patients with HIV/AIDS in the era of highly active antiretroviral therapy in Taiwan: A population-based cohort study

Objectives: HIV-related immunosuppression has been associated with the development of AIDS-defining malignancies. We examined the overall survival of HIV-infected patients who developed cancer. Design: A retrospective cohort study. Methods: Using the Taiwan Longitudinal Health Insurance Database, we compared patients diagnosed with HIV (n = 9918) between January 1, 2002, and December 31, 2007 with age-matched controls (n = 99,180). Each patient was followed until the end of 2009 (least 2 years after the initial HIV diagnosis) to evaluate the incidence of malignancies. Results: The risk of overall malignancies in the HIV-infected cohort was 1.88 times higher than the risk of a first malignancy in the age-matched non-HIV infected cohort (incidence rate ratio [IRR]) = 2.05, p < 0.0001). The diagnosis of a malignancy was negatively correlated with survival in the HIV-infected cohort (p < 0.0011), and HIV infection had a synergistic effect on the survival of patients with malignancies compared with the non-HIV infected cohort, all of who had been newly diagnosed with cancer (p < 0.0001). However, the difference in the risk of developing nasopharyngeal carcinoma (NPC), a highly prevalent malignancy in Taiwan, between the two cohorts was not significant (IRR = 0.22, 95% CI = 0.03–1.65). Conclusions: The risk of cancer in HIV-infected patients in Taiwan has increased significantly in the era of highly active antiretroviral therapy. A history of HIV significantly affected the survival of the patients in our study cohort after they developed cancer.Evidence level: 2B.     

Cancer risks in children with congenital malformations in the nervous and circulatory system—A population based cohort study

AimWe estimated the age and organ-specific cancer risk for children with a congenital malformation (CM) in the nervous or in the circulatory system.MethodsWe identified 1,709,456 live born singletons in Denmark between 1 January 1977 and 31 December 2007 and excluded children with chromosomal birth defects. Information on CMs was obtained from the Danish National Hospital Register. Information on cancer occurrence was obtained from the Danish Cancer Registry. We applied Cox proportional hazards regression model to estimate hazard ratios (HR) for cancer. Children entered into the CM cohort on the day of birth regardless of when the CM was diagnosed or on the day of CM diagnosis in an alternative analysis.ResultsOverall, 4484 (0.26%) and 24,643 (1.44%) children were diagnosed with a CM in the nervous and in the circulatory system, respectively. Compared with children without any CM, children with a CM in the nervous system had a 5.97 fold (95%CI [confidence interval]: 4.66–7.64) higher risk of cancer, including cancer in the central nervous system (HR = 18.84, 95%CI: 12.67–28.01), in the mesothelial and soft tissue (HR = 15.64, 95%CI: 7.99–30.60), in the skin (HR = 4.91, 95%CI: 2.19–11.0). The associations were stronger early in life. Children with a CM in the circulatory system had a 2.64 fold (95%CI: 2.21–3.16) higher risk of cancer, including cancer in the lymphatic and haematopoietic tissues (HR = 3.22, 95%CI: 2.43–4.27) and cancer in the CNS (HR = 2.40, 95%CI: 1.43–4.02). Some of these associations were weaker in the alternative analysis. Children with subtypes of CM in the two systems showed a higher cancer risk.ConclusionsChildren who were diagnosed with a CM in the nervous system had a substantially higher cancer risk especially early in life. Children diagnosed with a CM in the circulatory system had a moderately higher cancer risk.     

Reproductive factors,exogenous hormone use,and risk of pancreatic cancer in postmenopausal women

IntroductionThe epidemiologic literature on menstrual and reproductive factors associated with pancreatic cancer has yielded weak and inconsistent evidence of an association. Furthermore, few cohort studies have examined the association of exogenous hormone use, including type and duration, with this disease. The aim of this study was to assess the association of these exposures with risk of pancreatic cancer in a large cohort of postmenopausal women.MethodsWe used data from the Women’s Health Initiative on 1003 cases of pancreatic cancer diagnosed among 158,298 participants over 14.3 years of follow-up. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) for the associations of interest.ResultsBeing parous vs. nulliparous was associated with reduced risk (HR = 0.84, 95% CI 0.70–1.00), and women who had 1–2 and 3–4 births were at decreased risk compared to nulliparous women, whereas women who had >5 births showed no decrease in risk. Compared to women who gave birth between the ages of 20–29, women who gave birth at age 30 or above were at increased risk (HR 1.23, 95% CI 1.00–1.53, p for trend 0.003). Other reproductive factors and exogenous hormone use were not associated with risk.ConclusionsTogether with the existing literature on this topic, our results suggest that reproductive and hormonal exposures are unlikely to play an important role in the etiology of pancreatic cancer.     

Acute myeloid leukemia incidence following radiation therapy for localized or locally advanced prostate adenocarcinoma

Introduction: The effect of radiation therapy on acute myeloid leukemia incidence among prostate cancer patients has not been sufficiently elucidated despite evidence that acute myeloid leukemia is a consequence of therapeutic radiation in other primary malignancies. Therefore, we investigated the effect of definitive therapy with radiation therapy (external beam radiation therapy [EBRT] or brachytherapy) on acute myeloid leukemia incidence in a population-based cohort of patients with localized or locally advanced prostate cancer. Methods: We utilized the Surveillance, Epidemiology, and End Results database to identify a cohort of men (n = 168,612) with newly diagnosed prostate adenocarcinoma between January 1988 and December 2003. Cox proportional hazard regression was used to estimate the hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) of acute myeloid leukemia incidence following definitive therapy with EBRT alone, brachytherapy alone, or surgery alone compared to no definitive therapy (i.e. no EBRT, brachytherapy, or surgery). Results: The cohort yielded 184 acute myeloid leukemia cases during 1,064,820 person-years of follow-up after prostate adenocarcinoma diagnosis. Patients treated with EBRT had a higher adjusted relative risk of developing acute myeloid leukemia than patients treated with brachytherapy or surgery when each therapy group was compared to patients who were not treated with definitive therapy (EBRT: HR = 2.05, 95% CI 1.29, 3.26; brachytherapy: HR = 1.22, 95% CI 0.46, 3.22; surgery: HR = 1.24, 95% CI 0.77, 1.98). Conclusions: Our findings suggest that acute myeloid leukemia incidence is a greater concern for patients treated with EBRT than brachytherapy for localized or locally advanced prostate adenocarcinoma.     

Age–period–cohort analysis of colorectal cancer in East Anglia, 1971–2005

Background: This study aimed to investigate the incidence trends of colorectal cancer by sex and subsite, in East Anglia from 1971 to 2005. Methods: Using data from the Eastern Cancer Registration and Information Centre, we examined the time trends and the effect of age, period of diagnosis and birth cohort on the incidence of colorectal cancer by sex and subsite. Results: Between 1971 and 2005, 23 875 males and 22 651 females were registered with colorectal cancer in East Anglia. During this period, the increase in the incidence trends was higher among males, more recent periods of diagnosis, and proximal colon. Cohort effects were statistically significant in distal and rectal cancers in males (p < 0.001 and p = 0.05, respectively), and in proximal colon in females (p < 0.001). Period effects were statistically significant across all subsites and both sexes (p < 0.001 for all). Conclusions: Period effects were significant across all subsites for both sexes, whereas cohort effects varied in their significance levels depending on subsite and sex. We suggest that the period effect may be due to an increase in the use of colonoscopy for diagnostic or opportunistic screening, and the cohort effect may be due to aetiological differences in CRC between sexes and subsites.     

Active cigarette smoking and the risk of breast cancer: a cohort study

BackgroundTobacco use has been implicated in the etiology of a large number of cancers, and there exists substantial biological plausibility that it could also be involved in breast carcinogenesis. Despite this, epidemiological evidence to date is inconsistent. The aim of this study was to investigate the role of active smoking and the risk of incident, invasive breast cancer using a prospective cohort of women from the Canadian Study of Diet, Lifestyle and Health.MethodsUsing a case-cohort design, an age-stratified subcohort of 3314 women was created from 39,532 female participants who returned completed self-administered lifestyle and dietary questionnaires at baseline. A total of 1096 breast cancer cases were identified in the entire cohort (including 141 cases from the subcohort) by linkage to the Canadian Cancer Registry. Cox regression models were used to estimate hazard ratios for the association between the different smoking exposures and the risk of breast cancer, using a modification for the case-cohort design.ResultsAfter carefully considering early-life exposures and potential confounders, we found no association between any smoking exposure and risk of breast cancer in this study (Hazard ratio = 1.00, 95% confidence interval = 0.87–1.17 for ever vs never smokers).ConclusionsAlthough these results cannot rule out an association between smoking and breast cancer, they do agree with the current literature suggesting that, if an association does exist, it is relatively weak.     

Cancer mortality and occupational exposure to aromatic amines and inhalable aerosols in rubber tire manufacturing in Poland

Aim: Most data on carcinogenic risk in the rubber industry are based on data from Western countries. This study assessed cancer risks in a retrospective cohort in a Polish tire manufacturing plant, relying on quantified exposure to inhalable aerosols and aromatic amines instead of job titles or external comparisons. Methods: Cumulative exposure for all exposures was assigned to cohort members based on estimates from a company-specific JEM. Cancer risks associated with cumulative exposure adjusted for co-exposures, gender and year of birth were calculated. Results: Exposure levels were higher for women than for men. Aromatic amine exposure was significantly associated with increased urinary bladder cancer risk (RR = 7.32–8.27), depending on exposure level, and prostate cancer at low levels only (RR = 5.86). In women, increased risks were found for all cancers (RR = 2.50) and of the digestive organs and peritoneum (RR = 4.54) at low level only, while an exposure-response association with breast cancer risk was found. Inhalable aerosol exposure was associated with cancers of the liver and intrahepatic bile ducts in a dose-dependent manner, while dose-dependent reduced risks were found for respiratory cancers (most notably the larynx) and cancer of the colon. Conclusions: Increased risks for specific cancer sites in this rubber plant were similar to Western Europe and the US. However, several cancer risks were gender-specific which could relate to higher exposure levels in women or to differences in exposures to chemicals not assessed in this study.     

Recent changes in endometrial cancer trends among menopausal-age US women

BackgroundChanges in endometrial cancer incidence rates after the precipitous decline in menopausal hormone therapy (MHT) use in 2002 have not been evaluated.MethodsUsing data from the Surveillance, Epidemiology, and End Results Program from 1992 to 2009 (SEER 13), we identified 63 428 incident endometrial cancer cases among women ages 20–74. We compared annual percent change (APC) in endometrial cancer incidence rates from 1992 to 2002 to rates from 2003 to 2009.ResultsIn contrast to the constant endometrial cancer rate pattern observed from 1992 to 2002 (APC 0.0%), rates increased after 2002 in women 50–74 years old (2.5%; P_{APC comparison} < 0.01). Endometrial cancer incidence increased over the entire time period among women ages 20–49 (1992–2002: 1.1%; 2003–2009: 2.1%; P_{APC comparison} = 0.21). Post-2002 increases in incidence among women ages 50–74 were specific to Type I endometrial tumors (1992–2002: ?0.6%; 2003–2009: 1.6%; P_{APC comparison} < 0.01).DiscussionThe increase in endometrial cancer incidence rates after 2002 may be related to the widespread decrease in estrogen plus progestin MHT use, which has been reported to lower endometrial cancer risk in overweight and obese women.     

Associations of body mass index with cancer incidence among populations,genders, and menopausal status: A systematic review and meta-analysis

In order to further reveal the differences of association between body mass index (BMI) and cancer incidence across populations, genders, and menopausal status, we performed comprehensive meta-analysis with eligible citations. The risk ratio (RR) of incidence at 10 different cancer sites (per 5 kg/m² increase in BMI) were quantified separately by employing generalized least-squares to estimate trends, and combined by meta-analyses. We observed significantly stronger association between increased BMI and breast cancer incidence in the Asia⿿Pacific group (RR 1.18:1.11⿿1.26) than in European⿿Australian (1.05:1.00⿿1.09) and North-American group (1.06:1.03⿿1.08) (meta-regression p < 0.05). No association between increased BMI and pancreatic cancer incidence (0.94:0.71⿿1.24) was shown in the Asia⿿Pacific group (meta-regression p < 0.05), whereas positive associations were found in other two groups. A significantly higher RR in men was found for colorectal cancer in comparison with women (meta-regression p < 0.05). Compared with postmenopausal women, premenopausal women displayed significantly higher RR for ovarian cancer (pre- vs. post- = 1.10 vs. 1.01, meta-regression p < 0.05), but lower RR for breast cancer (pre- vs. post- = 0.99 vs. 1.11, meta-regression p < 0.0001). Our results indicate that overweight or obesity is a strong risk factor of cancer incidence at several cancer sites. Genders, populations, and menopausal status are important factors effecting the association between obesity and cancer incidence for certain cancer types.     

Does consanguinity lead to decreased incidence of breast cancer?

Background: In the Middle East region, consanguinity remains to be a central feature where it has shown an increasing trend. Breast cancer is an extremely complex disease, characterized by a progressive multistep process caused by interactions of both environmental and genetic factors. Aim: The aim of this study was to examine the possible effect of consanguinity on the risk of breast cancer in a population with a high rate of consanguinity and find the associated risk-modifying factors. Subjects and methods: The study included 167 Qatari and other Arab expatriates women with breast cancer and 341 age and ethnicity matched control women. A questionnaire that included the socio-demographic information, type of consanguinity, medical history, life style habits, dietary intake and tumor grade was designed to collect, the information of cases and controls. A total number of 214 breast cancer patients were approached and 167 cases completed the questionnaires with a response rate of 78%. Of the 417 healthy women who agreed to participate in this study, 341 responded to the questionnaire (81.8%). Results: The study revealed that the rate of parental consanguinity was lower in breast cancer patients (24%) than in controls (32.3%) (p = 0.062). Female controls were slightly younger (46.5 ± 11.9) than breast cancer patients (48.4 ± 10.7). Breast cancer incidence was significantly higher in Qatari women (34.1%) compared to other Arab women (65.9%) (p = 0.034). A significant difference was noted only in occupation of the studied women between cases and controls (p < 0.001). Overweight (46.7%) and obesity (32.9%) were significantly higher in female breast cancer patients compared to controls (p = 0.028). Overall, the mean coefficient of consanguinity was lower in breast cancer patients (0.014) than in controls (0.018) (p = 0.0125). Family history of breast cancer was significantly more often in breast cancer patients (14.4%) than in controls (6.2%) (p = 0.002). However, the family history of breast cancer was more often positive in cases of non-consanguineous parents (15.7%) than cases of consanguineous parents (10.0%). Conclusion: The present study revealed the lack of association between of breast cancer and the parental consanguinity in Arab women residing in Qatar. The family history of breast cancer and the body mass index (BMI) are highly associated with breast cancer.     

Recreational physical activity and risk of papillary thyroid cancer among women in the California Teachers Study

Purpose: Little is known about the relationship between physical activity and thyroid cancer risk, and few cohort data on this association exist. Thus, the present study aimed to prospectively examine long-term activity and risk of papillary thyroid cancer among women. Methods: 116,939 women in the California Teachers Study, aged 22–79 years with no history of thyroid cancer at cohort entry, were followed from 1995–1996 through 2009; 275 were diagnosed with invasive papillary thyroid cancer. Cox proportional-hazards regression provided relative risk (RR) estimates and 95% confidence intervals (CI) for associations between thyroid cancer and combined strenuous and moderate recreational physical activity both in the long-term (high school through age 54 years or current age if younger than 54 years) and recently (during the three years prior to joining the cohort). Results: Overall, women whose long-term recreational physical activity averaged at least 5.5 MET-hours/week (i.e. were active) had a non-significant 23% lower risk of papillary thyroid cancer than inactive women (RR = 0.77, 95% CI: 0.57, 1.04). RR estimates were stronger among normal weight or underweight women (body mass index, BMI < 25.0 kg/m², trend p = 0.03) than among overweight or obese women (trend p = 0.35; homogeneity-of-trends p = 0.03). A similar pattern of risk was observed for recent activity (BMI < 25 kg/m², trend p = 0.11; BMI ≥ 25 kg/m², trend p = 0.16; homogeneity-of-trends p = 0.04). Associations for long-term activity did not appear to be driven by activity in any particular life period (e.g. youth, adulthood). Conclusions: Long-term physical activity may reduce papillary thyroid cancer risk among normal weight and underweight women.     

Breast cancer detection risk in screening mammography after a false-positive result

Background: False-positives are a major concern in breast cancer screening. However, false-positives have been little evaluated as a prognostic factor for cancer detection. Our aim was to evaluate the association of false-positive results with the cancer detection risk in subsequent screening participations over a 17-year period. Methods: This is a retrospective cohort study of 762,506 women aged 45–69 years, with at least two screening participations, who underwent 2,594,146 screening mammograms from 1990 to 2006. Multilevel discrete-time hazard models were used to estimate the adjusted odds ratios (OR) of breast cancer detection in subsequent screening participations in women with false-positive results. Results: False-positives involving a fine-needle aspiration cytology or a biopsy had a higher cancer detection risk than those involving additional imaging procedures alone (OR = 2.69; 95%CI: 2.28–3.16 and OR = 1.81; 95%CI: 1.70–1.94, respectively). The risk of cancer detection increased substantially if women with cytology or biopsy had a familial history of breast cancer (OR = 4.64; 95%CI: 3.23–6.66). Other factors associated with an increased cancer detection risk were age 65–69 years (OR = 1.84; 95%CI: 1.67–2.03), non-attendance at the previous screening invitation (OR = 1.26; 95%CI: 1.11–1.43), and having undergone a previous benign biopsy outside the screening program (OR = 1.24; 95%CI: 1.13–1.35). Conclusion: Women with a false-positive test have an increased risk of cancer detection in subsequent screening participations, especially those with a false-positive result involving cytology or biopsy. Understanding the factors behind this association could provide valuable information to increase the effectiveness of breast cancer screening.     

Clinical outcomes of female breast cancer according to BRCA mutation status

BackgroundTo investigate breast cancer prognosis (disease-free (DFS) and overall survival (OS)) among carriers of germline BRCA mutations (BRCAm) in Denmark.MethodsWe identified all women in Central and Northern Denmark diagnosed with breast cancer during 2004–2011. We retrieved information on germline BRCAm testing from Clinical Genetics departments and clinical/treatment characteristics from population-based medical registries. Follow-up for recurrence, new primary cancer, and mortality extended from 180 days after diagnosis until 31/12/2012. We estimated median DFS and OS and five-year cumulative incidence and incidence rates (IR/1000 person-years), and 95% confidence intervals (95% CI), for each outcome.ResultsAmong 9874 patients, 523 (5%) underwent BRCA testing—90 were BRCAm carriers, 433 were BRCA wildtype (BRCAwt). Compared with BRCAwt women, BRCAm carriers were younger, had lower stage, and ER- and HER2- tumors. Median time from diagnosis to BRCA testing was 0.91 years and 1.3 years in BRCAm and BRCAwt women; median follow-up to first event was 3.9 and 3.4 years, respectively. Five-year DFS and OS were higher in BRCAm than BRCAwt women: 88% (95%CI = 78.3–93.5) vs. 75.3% (95%CI = 70.2–79.6) and 97.8% (95%CI = 91.4–99.4) vs 92.2% (95%CI = 88.5–94.7), respectively. Five-year IRs of recurrence were 36.7/1000 person-years (95%CI = 15.8–72.2) in the BRCAm cohort vs. 58.4 (95%CI = 42.9–77.6) in the BRCAwt cohort.ConclusionsBRCAm carriers may have a better prognosis than BRCAwt women. However, limited testing conducted mainly during follow-up, yielded low numbers for precise estimations, and may be attributable to selection bias.     

Cancer incidence in the Western Australian mining industry (1996–2013)

BackgroundMiners are frequently exposed to established and potential carcinogens. We aimed to assess cancer incidence in miners relative to the general population and identify high-risk subgroups.MethodsIncident cancers in Western Australian miners (n = 153,922; 86% male) during 1996–2013 were identified. Indirectly standardised incidence ratios (SIRs) were calculated and mixed-effects Poisson models were used to calculate Incidence Rate Ratios (IRRs) to identify high-risk within-cohort subgroups.ResultsCompared with the general population, the overall cancer incidence in miners (n = 4194 cases) was lower for both females (SIR:0.83, 95%CI:0.74–0.92) and males (SIR:0.96, 95%CI:0.93–0.99). Overall, cancer incidence did not differ by employment duration or employment commencement time. Ever-underground work was associated with lung cancer (IRR:1.81, 95%CI:1.11–2.93). Relative to multi-ore miners, IRRs for specific cancers were significantly different when exclusively mining: iron (prostate:0.73, 95%CI:0.56–0.94); gold (lung:1.77, 95%CI:1.04–3.01 and colorectum:1.70, 95%CI:1.16–2.51); and other metals (urinary tract:1.85, 95%CI:1.03–3.31 and leukaemia:0.36, 95%CI:0.14–0.96).ConclusionWorking underground emerged as a significant determinant of lung cancer risk in our contemporary mining cohort. Increased risks of lung, prostate, colorectal and urinary tract cancers and leukaemia were identified in miners of specific ores. These findings underline the importance of continued surveillance of the health and exposures of this relatively young cohort of miners.     

Fallout from the Chernobyl accident and overall cancer incidence in Finland

Aim: We studied whether incidence of all cancer sites combined was associated with the radiation exposure due to fallout from the Chernobyl accident in Finland. An emphasis was on the first decade after the accident to assess the suggested “promotion effect”. Methods: The segment of Finnish population with a stable residence in the first post-Chernobyl year (2 million people) was studied. The analyses were based on a 250 m × 250 m grid squares covering all of Finland and all cancer cases except cancers of the breast, prostate and lung. Cancer incidence in four exposure areas (based on first-year dose due to external exposure <0.1 mSv, 0.1–1.3, 0.3–0.5, or ≥0.5 mSv) was compared before the Chernobyl accident (1981–1985) and after it (1988–2007) taking into account cancer incidence trends for a longer period prior to the accident (since 1966). Results: There were no systematic differences in the cancer incidence in relation to radiation exposure in any calendar period, or any subgroup by sex or age at accident. Conclusion: The current large and comprehensive cohort analysis of the relatively low levels of the Chernobyl fallout in Finland did not observe a cancer promotion effect.