Obstetric and perinatal outcomes in women with previous breast cancer: a nationwide study of singleton births 1973-2017.

STUDY QUESTION: What are the obstetric and perinatal outcomes in births to breast cancer survivors compared to women without previous breast cancer? SUMMARY ANSWER: Women who conceived during the first 2 years following a breast cancer diagnosis had a higher risk for preterm birth, induced delivery, and cesarean section, while no increased risks were observed in births conceived later than 2 years after a breast cancer diagnosis. WHAT IS KNOWN ALREADY: A recent meta-analysis found higher risks of cesarean section, preterm birth, low birthweight, and small for gestational age in pregnancies among breast cancer survivors. Less is known about rarer outcomes such as pre-eclampsia or congenital malformations. STUDY DESIGN SIZE DURATION: We conducted a population-based matched cohort study including all breast cancer survivors who gave birth to singletons 1973-2017 in Sweden, identified through linkage between the Swedish Cancer Register, the Medical Birth Register, and the National Quality Register for Breast Cancer. PARTICIPANTS/MATERIALS SETTINGS METHODS: Each birth following breast cancer (n = 926) was matched by maternal age at delivery, parity, and calendar year at delivery to 100 births in a comparator cohort of women (n = 92 490). Conditional logistic and multinomial regression models estimated relative risks (RR) with 95% CI. Subgroup analyses by time since diagnosis and type of treatment were performed. MAIN RESULTS AND THE ROLE OF CHANCE: Previous breast cancer was associated with higher risks of induced delivery (RR; 1.3, 1.0-1.6), very preterm birth (RR; 1.8, 1.1-3.0), and planned preterm birth (RR; 1.6, 1.0-2.4). Women who conceived within 1 year after breast cancer diagnosis had higher risks of cesarean section (RR; 1.7, 1.0-2.7), very preterm birth (RR; 5.3, 1.9-14.8), and low birthweight (RR; 2.7, 1.4-5.2), while the risks of induced delivery (RR; 1.8, 1.1-2.9), moderately preterm birth (RR; 2.1, 1.2-3.7), and planned preterm birth (RR; 2.5, 1.1-5.7) were higher in women who conceived during the second year after diagnosis. Women who conceived later than 2 years after breast cancer diagnosis had similar obstetric risks to their comparators. LIMITATIONS REASONS FOR CAUTION: As information on the end date of treatment was unavailable, the time between the date of diagnosis and conception was used as a proxy, which does not fully capture the effect of time since end of treatment. In addition, treatments and clinical recommendations have changed over the long study period, which may impact childbearing patterns in breast cancer survivors. WIDER IMPLICATIONS OF THE FINDINGS: Risks of adverse obstetric outcomes in breast cancer survivors were confined to births conceived within 2 years of diagnosis. As family building holds significance for numerous young breast cancer patients, these findings are particularly important to inform both breast cancer survivors and clinicians about future reproductive outcomes. STUDY FUNDING/COMPETING INTERESTS: This work was supported by the Swedish Cancer Society (grant number 22-2044 Pj A.L.V.J.), Karolinska Institutet Foundations (grant number: 2022-01696 F.E.L., 2022-01559 A.L.V.J.), and the Swedish Research Council (grant number: 2021-01657 A.L.V.J.). K.A.R.-W. is supported by grants from the Swedish Cancer Society (20 0170 F) and the Radiumhemmets Research Foundations for clinical researchers 2020-2026. The authors declare that they have no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Real-world overall survival and characteristics of patients with ER-zero and ER-low HER2-negative breast cancer treated as triple-negative breast cancer: a Swedish population-based cohort study.

Background: Estrogen receptor-low (ER-low) HER2-negative breast cancer has similar pathological and molecular characteristics as triple-negative breast cancer (TNBC), and it is questionable whether it should be considered a separate entity. When the international guidelines lowered the cutoff for ER positivity to ≥1% in 2010, the ≥10% threshold was kept in Sweden. ER-low breast cancer (ER 1-9%) is thus in Sweden treated as TNBC. We aimed to describe patient and tumor characteristics, treatment patterns and overall survival in a Swedish population-based cohort of patients with ER-zero and ER-low HER2-negative breast cancer treated as TNBC. Methods: All TNBC cases diagnosed in Sweden 2008-2020 were included in a population-based cohort study. Patient, tumor and treatment characteristics were analyzed by ER-status (ER 0% vs 1-9%), and associations between subgroups compared using χ2 test. Survival endpoint was overall survival (OS), and Kaplan-Meier curves were estimated. Cox proportional hazards models were used to estimate adjusted hazard ratios comparing ER-low to ER-zero. Findings: Of the 5655 tumors, 90.1% had an ER expression of 0%, while 9.9% were ER-low. ER-low tumors were grade III in 69.4% (80.8% in ER-zero tumors, p-value = 0.001), with a median Ki67 of 60% (63% in ER-zero tumors, p-value = 0.005). There were no significant differences in given chemotherapy (p = 0.546). A pathological complete response (pCR) was achieved in 28.1% of ER-low tumors (25.1% in ER-zero tumors). In the unadjusted analysis of OS, women with ER-low disease had a borderline but not significantly better OS than those with ER-zero disease (HR 0.84 (95% CI 0.71-1.00), p = 0.052). ER-status 1-9% vs 0% was not associated with OS in the multivariable analysis (HR 1.11 (0.90-1.36)). Distant disease-free survival did not differ by ER-status 0% vs 1-9% (HR 0.97 for ER-zero vs ER-low (0.62-1.53), p = 0.905). After preoperative treatment, the impact of pCR for OS did not significantly differ between ER-zero or ER-low disease. Interpretation: ER-low HER2-negative breast cancer has characteristics and prognosis similar to TNBC, when treated in the same way. Therefore, it seems reasonable to use a ≥10% threshold for ER positivity. This would provide patients with ER-low tumors the same treatment opportunities as patients with TNBC, within studies and within clinical routine. Funding: This work was financially supported by Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA, in accordance with terms and conditions of a Master Collaboration Agreement between the company and Karolinska Institutet.

Trends in lung cancer survival in the Nordic countries 1990-2016: The NORDCAN survival studies.

OBJECTIVES: The aim of this study was to evaluate if the previously reported improvements in lung cancer survival were consistent across age at diagnosis and by lung cancer subtypes. MATERIALS AND METHODS: Data on lung cancers diagnosed between 1990 and 2016 in Denmark, Finland, Iceland, Norway and Sweden were obtained from the NORDCAN database. Flexible parametric models were used to estimate age-standardized and age-specific relative survival by sex, as well as reference-adjusted crude probabilities of death and life-years lost. Age-standardised survival was also estimated by the three major subtypes; adenocarcincoma, squamous cell and small-cell carcinoma. RESULTS: Both 1- and 5-year relative survival improved continuously in all countries. The pattern of improvement was similar across age groups and by subtype. The largest improvements in survival were seen in Denmark, while improvements were comparatively smaller in Finland. In the most recent period, age-standardised estimates of 5-year relative survival ranged from 13% to 26% and the 5-year crude probability of death due to lung cancer ranged from 73% to 85%. Across all Nordic countries, survival decreased with age, and was lower in men and for small-cell carcinoma. CONCLUSION: Lung cancer survival has improved substantially since 1990, in both women and men and across age. The improvements were seen in all major subtypes. However, lung cancer survival remains poor, with three out of four patients dying from their lung cancer within five years of diagnosis.

TNM stage in the Nordic Cancer Registries 2004-2016: Registration and availability.

BACKGROUND AND PURPOSE: Stage at cancer diagnosis is an important predictor of cancer survival. TNM stage is constructed for anatomic solid cancer diagnoses from tumor size (T), nodal spread (N) and distant metastasis (M) and categorized in groups 0-I, II, II and IV. TNM stage is imperative in cancer diagnosis, management and control, and of high value in cancer surveillance, for example, monitoring of stage distributions. This study yields an overview of TNM availability and trends in stage distribution in the Nordic countries for future use in monitoring and epidemiologic studies. MATERIAL AND METHODS: TNM information was acquired from the cancer registries in Denmark, Norway, Sweden, and Iceland during 2004-2016 for 26 cancer sites in the three former countries and four in Iceland. We studied availability, comparability, and distribution of TNM stage in three periods: 2004-2008, 2009-2013, and 2014-2016, applying a previously validated algorithm of 'N0M0 for NXMX'. For cancers of colon, rectum, lung, breast, and kidney, we examined TNM stage-specific 1-year relative survival to evaluate the quality in registration of TNM between countries. RESULTS: Denmark, Sweden, and Iceland exhibited available TNM stage proportions of 75-95% while proportions were lower in Norway. Proportions increased in Sweden over time but decreased in Denmark. One-year relative survival differed substantially more between TNM stages than between countries emphasizing that TNM stage is an important predictor for survival and that stage recording is performed similarly in the Nordic countries. INTERPRETATION: Assessment and registration of TNM stage is an imperative tool in evaluations of trends in cancer survival between the Nordic countries.

Have the recent advancements in cancer therapy and survival benefitted patients of all age groups across the Nordic countries? NORDCAN survival analyses 2002-2021.

BACKGROUND: Since the early 2000s, overall and site-specific cancer survival have improved substantially in the Nordic countries. We evaluated whether the improvements have been similar across countries, major cancer types, and age groups. MATERIAL AND METHODS: Using population-based data from the five Nordic cancer registries recorded in the NORDCAN database, we included a cohort of 1,525,854 men and 1,378,470 women diagnosed with cancer (except non-melanoma skin cancer) during 2002-2021, and followed for death until 2021. We estimated 5-year relative survival (RS) in 5-year calendar periods, and percentage points (pp) differences in 5-year RS from 2002-2006 until 2017-2021. Separate analyses were performed for eight cancer sites (i.e. colorectum, pancreas, lung, breast, cervix uteri, kidney, prostate, and melanoma of skin). RESULTS: Five-year RS improved across nearly all cancer sites in all countries (except Iceland), with absolute differences across age groups ranging from 1 to 21 pp (all cancer sites), 2 to 20 pp (colorectum), -1 to 36 pp (pancreas), 2 to 28 pp (lung), 0 to 9 pp (breast), -11 to 26 pp (cervix uteri), 2 to 44 pp (kidney), -2 to 23 pp (prostate) and -3 to 30 pp (skin melanoma). The oldest patients (80-89 years) exhibited lower survival across all countries and sites, although with varying improvements over time. INTERPRETATION: Nordic cancer patients have generally experienced substantial improvements in cancer survival during the last two decades, including major cancer sites and age groups. Although survival has improved over time, older patients remain at a lower cancer survival compared to younger patients.

Survival trends for patients diagnosed with cutaneous malignant melanoma in the Nordic countries 1990-2016: The NORDCAN survival studies.

BACKGROUND: The survival in patients diagnosed with cutaneous malignant melanoma (CMM) has improved in the Nordic countries in the last decades. It is of interest to know if these improvements are observed in all ages and for both women and men. METHODS: Patients diagnosed with CMM in the Nordic countries in 1990-2016 were identified in the NORDCAN database. Flexible parametric relative survival models were fitted, except for Iceland where a non-parametric Pohar-Perme approach was used. A range of survival metrics were estimated by sex, both age-standardised and age-specific. RESULTS: The 5-year relative survival improved in all countries, in both women and men and across age. While the improvement was more pronounced in men, women still had a higher survival at the end of the study period. The survival was generally high, with age-standardised estimates of 5-year relative survival towards the end of the study period ranging from 85% in Icelandic men to 95% in Danish women. The age-standardised and reference-adjusted 5-year crude probability of death due to CMM ranged from 5% in Danish and Swedish women to 13% in Icelandic men. CONCLUSION: Although survival following CMM was relatively high in the Nordic countries in 1990, continued improvements in survival were observed throughout the study period in both women and men and across age.

Time trends in the use of curative treatment in men 70 years and older with nonmetastatic prostate cancer.

BACKGROUND: Undertreatment of otherwise healthy men in their seventies with prostate cancer has been reported previously. MATERIAL AND METHODS: Using information in a Swedish prostate cancer research database, patterns of management and cancer-specific mortality were compared across age groups in over 70,000 men diagnosed with intermediate- or high-risk nonmetastatic prostate cancer between 2008 and 2020. Crude probabilities of death were estimated non-parametrically. Staging procedures, primary treatment, and cancer death were compared using regression models, adjusting for patient and tumor characteristics. RESULTS: During the study period, the proportion of men treated with curative intent increased in ages 70-74 (intermediate-risk from 45% to 72% and high-risk from 49% to 84%), 75-79 (intermediate-risk from 11% to 52% and high-risk from 12% to 70%), and 80-84 years (intermediate-risk from < 1% to 14% and high-risk from < 1% to 30%). Older age was associated with lower likelihoods of staging investigations and curative treatment, also after adjustment for tumor characteristics and comorbidity. Men treated with curative intent and those initially managed conservatively had lower crude risks of prostate cancer death than men receiving androgen deprivation treatment (ADT). In adjusted analyses, ADT was associated with higher prostate cancer mortality than curative treatment across ages and risk groups. Among men managed conservatively, prostate cancer mortality was higher in ages 70 and above. INTERPRETATION: Use of curative treatment increased substantially in older men with prostate cancer between 2008 and 2020. Our findings suggest reduced age-bias and under-treatment, likely reflecting improved individualized decision-making and adherence to guidelines recommending more active management of older men.

Childbirth rates in women with myeloproliferative neoplasms.

Myeloproliferative neoplasms (MPN) are associated with inferior pregnancy outcome, however, little is known about fertility and childbearing potential in women with MPN. In this study we aimed to describe reproductive patterns, as well as to quantify risk of miscarriage and stillbirth. Women aged 15-44 years with an MPN diagnosis 1973-2018, were identified in Swedish health care registers, and age-matched 1:4 to population controls. We identified 1141 women with MPN and 4564 controls. Women with MPN had a lower rate of childbirth (hazard ratio [HR] with 95% confidence interval was 0.78 (0.68-0.90)). Subgroup analysis showed that the rate was not significantly reduced in essential thrombocythemia, HR 1.02 (0.86-1.22) while the HR was 0.50 (0.33-0.76) in PV and 0.45 (0.28-0.74) in PMF. The risk of miscarriage was not significantly increased before MPN diagnosis, the HR during follow-up after diagnosis was 1.25 (0.89-1.76). Women with MPN were more likely to have had a previous stillbirth. Women with MPN had fewer children at diagnosis, and fewer children in total. In conclusion, the childbirth rate was lower among women with MPN than controls, but not among women with essential thrombocythemia.

Risk of obstetric and perinatal complications in women presenting with breast cancer during pregnancy and the first year postpartum in Sweden 1973-2017: A population-based matched study.

INTRODUCTION: For women presenting with breast cancer during pregnancy, treatment guidelines were historically restricted to only surgical treatment. Over the past decades, chemotherapy administered during pregnancy has been gradually introduced. Although breast cancer treatments during ongoing pregnancy have been deemed safe, detailed information on potential obstetric risks is lacking. We aimed to assess the risk of adverse obstetric and perinatal outcomes of breast cancer in pregnancy and within 1 year postpartum and in relation to trimester at breast cancer diagnosis, tumor stage, and cancer treatment during pregnancy. MATERIAL AND METHODS: Population-based matched study. Women diagnosed with breast cancer during pregnancy in 1973-2017 were identified in the Swedish Cancer Register and the Medical Birth Register, with additional information from the National Quality Register for Breast Cancer. Each birth with maternal breast cancer (n = 208 pregnant, n = 672 postpartum) was matched by age, calendar year, and birth order to 10 unexposed births from cancer-free women in the population (n = 2080 and n = 6720). Adjusted conditional logistic and multinomial regression models were used to estimate odds ratios and relative risk ratios, commonly denoted relative risks (RR) with 95% confidence intervals (CI), of adverse obstetric and perinatal outcomes. RESULTS: Breast cancer during pregnancy was associated with higher risks of preterm birth, both planned (RR 67.1, 95% CI 33.2-135.6) and spontaneous preterm birth (RR 3.8, 95% CI 2.0-7.5), and low birthweight (<2500 g: RR 7.5, 95% CI 4.9-11.3). The associated risks were higher if the breast cancer was diagnosed in the second trimester, and of similar magnitude irrespective of stage and treatment groups. There was a higher risk of low birthweight for gestational age (<25th centile) if breast cancer was diagnosed in the first trimester (RR 2.8, 95% CI 1.1-7.3). Risks of other pregnancy complications were similar to those of unexposed women, as were risks of neonatal mortality and malformations. Postpartum breast cancer was only associated with bleeding during pregnancy (RR 1.6, 95% CI 1.0-2.8). CONCLUSIONS: Preterm birth and related adverse outcomes were more common in women diagnosed with breast cancer during pregnancy. Reassuringly, breast cancer was not associated with other maternal pregnancy complications or adverse outcomes in children.

Risk factors for the increasing incidence of pregnancy-associated cancer in Sweden - a population-based study.

INTRODUCTION: The incidence of cancer during pregnancy and within first year post-delivery, ie pregnancy-associated cancer (PAC), is increasing in many countries, but little is known about risk factors for these trends. This study quantified incidence of PAC by trimesters and post-delivery periods, and assessed the role of maternal age, parity, immigrant status, education, smoking and body mass index for the risk and incidence trends of PAC. MATERIAL AND METHODS: We used data from the national birth and cancer registers in Sweden during 1973-2017 to define a register-based cohort of women aged 15-44 years. Incidence rates of PAC during pregnancy and up to 1 year post-delivery were calculated per 100 000 deliveries per year. Poisson regression with multiple imputation estimated incidence rate ratios with 95% confidence intervals adjusted by year, age, previous parity, immigrant status, education, smoking and BMI during 1990-2017, when information on risk factors was available. RESULTS: Among 4 557 284 deliveries, a total of 1274 (during pregnancy) and 3355 (within 1 year post-delivery) cases of PAC were diagnosed, with around 50 cases/year diagnosed during pregnancy and 110 cases/year during the first year post-delivery in the latest period 2015-2017. The most common cancer types during pregnancy were malignant melanoma, breast and cervical cancer, together accounting for 57% of cases during pregnancy and 53% during the first year post-delivery. The numbers of PAC were lower during pregnancy than during post-delivery for all tumor types with lowest numbers during first trimester. The PAC incidence rates increased over calendar time. High maternal age at diagnosis, smoking, nulliparity and non-immigrant background were associated with significantly higher risks of PAC. The increasing PAC incidence was in part explained by higher maternal age over time, but not by the other factors. CONCLUSIONS: High maternal age is the strongest risk factor for PAC. We show for the first time that smoking, nulliparity and non-immigrant background are also contributing risk factors for PAC. However, only high maternal age contributed significantly to the increasing incidence. Further studies on other potential risk factors for PAC are warranted, since our results indicate that age on its own does not fully explain the increase.

Were cancer patients worse off than the general population during the COVID-19 pandemic? A population-based study from Norway, Denmark and Iceland during the pre-vaccination era.

Background: In a population-based setting, we investigated the risks of testing positive for SARS-CoV-2 and developing severe COVID-19 outcomes among cancer patients compared with the general population. Methods: In nationwide cohorts, we identified all individuals in Norway, Denmark and Iceland who tested positive for SARS-CoV-2 or had a severe COVID-19 outcome (hospitalisation, intensive care, and death) from March until December 2020, using data from national health registries. We estimated standardised incidence ratios (SIRs) with 95% confidence intervals (CIs) comparing cancer patients with the general population. Findings: During the first wave of the pandemic, cancer patients in Norway and Denmark had higher risks of testing SARS-CoV-2 positive compared to the general population. Throughout 2020, recently treated cancer patients were more likely to test SARS-CoV-2 positive. In Iceland, cancer patients experienced no increased risk of testing positive. The risk of COVID-19-related hospitalisation was higher among cancer patients diagnosed within one year of hospitalisation (Norway: SIR = 2.43, 95% CI 1.89-3.09; Denmark: 2.23, 1.96-2.54) and within five years (Norway: 1.58, 1.35-1.83; Denmark: 1.54, 1.42-1.66). Risks were higher in recently treated cancer patients and in those diagnosed with haematologic malignancies, colorectal or lung cancer. Risks of COVID-19-related intensive care and death were higher among cancer patients. Interpretation: Cancer patients were at increased risk of testing positive for SARS-CoV-2 during the first pandemic wave when testing availability was limited, while relative risks of severe COVID-19 outcomes remained increased in cancer patients throughout 2020. Recent cancer treatment and haematologic malignancy were the strongest risk factors. Funding: Nordic Cancer Union.

Improving communication of cancer survival statistics-feasibility of implementing model-based algorithms in routine publications.

BACKGROUND: Routine reporting of cancer patient survival is important, both to monitor the effectiveness of health care and to inform about prognosis following a cancer diagnosis. A range of different survival measures exist, each serving different purposes and targeting different audiences. It is important that routine publications expand on current practice and provide estimates on a wider range of survival measures. We examine the feasibility of automated production of such statistics. METHODS: We used data on 23 cancer sites obtained from the Cancer Registry of Norway (CRN). We propose an automated way of estimating flexible parametric relative survival models and calculating estimates of net survival, crude probabilities, and loss in life expectancy across many cancer sites and subgroups of patients. RESULTS: For 21 of 23 cancer sites, we were able to estimate survival models without assuming proportional hazards. Reliable estimates of all desired measures were obtained for all cancer sites. DISCUSSION: It may be challenging to implement new survival measures in routine publications as it can require the application of modeling techniques. We propose a way of automating the production of such statistics and show that we can obtain reliable estimates across a range of measures and subgroups of patients.

Influence of various assumptions for the individual TNM components on the TNM stage using Nordic cancer registry data.

BACKGROUND: The stage at diagnosis is one of the most important predictors for cancer survival. TNM stage is constructed from T (tumor size), N (nodal spread), and M (distant metastasis) components. In many notifications to cancer registries, TNM information is incomplete with unknown N and/or M. We aimed to evaluate the influence of various assumptions for recoding missing N (NX) and M (MX) as N0 and M0 on the proportion with available TNM stage, stage-distribution, and stage-specific relative survival. MATERIAL AND METHODS: We identified 140,201 patients diagnosed with incident cancer of the colon, rectum, lung, breast, or kidney during 2014-2016 in Denmark, Norway, Sweden, or Iceland. Information on TNM were obtained from cancer registry records used for an update of the Nordic cancer statistics database NORDCAN. Patients were followed for death or emigration through 2017. We calculated proportions of available TNM stage, stage distribution, and stage-specific relative survival under different approaches for each cancer site and country. RESULTS: Application of the assumptions yielded higher numbers of cases with available TNM stage for stages 0-I, II, and III. We observed only minor differences in stage-specific one-year relative survival when applying N0M0 for missing N and M, especially for high completeness of TNM registrations, whereas relative survival for remaining cases with missing TNM stage declined substantially. CONCLUSION: We found no major changes in stage-specific one-year relative survival applying N0M0 for NXMX. We conclude that complete TNM information is preferable to making assumptions, but it seems reasonable to consider assuming N0M0 for missing N and M in future studies based on the Nordic cancer registries. An automatic algorithm, though, is not recommended without considering potential area-specific reasons for frequent use of NX and MX. Clinicians should be urged to report complete TNM information to improve surveillance of the TNM stage.

Early Life Environmental Exposure to Cadmium, Lead, and Arsenic and Age at Menarche: A Longitudinal Mother-Child Cohort Study in Bangladesh.

BACKGROUND: Several metals act as endocrine disruptors, but there are few large longitudinal studies about associations with puberty onset. OBJECTIVES: We evaluated whether early life cadmium, lead, and arsenic exposure was associated with timing of menarche. METHODS: In a mother-child cohort in rural Bangladesh (n=935), the exposure was assessed by concentrations in maternal erythrocytes in early pregnancy and in girls' urine at 5 and 10 years of age using inductively coupled plasma mass spectrometry. The girls were interviewed twice, at average ages 13.3 [standard deviation (SD)=0.43] and 13.8 (SD=0.43) y, and the date of menarche, if present, was recorded. Associations were assessed using Kaplan-Meier analysis and multivariable-adjusted Cox regression. RESULTS: In total, 77% of the girls (n=717) had reached menarche by the second follow-up. The median age of menarche among all girls was 13.0 y (25th-75th percentiles: 12.4-13.7 y). At 10 years of age, median urinary cadmium was 0.25µg/L (5th-95th percentiles: 0.087-0.72µg/L), lead 1.6µg/L (0.70-4.2µg/L), and arsenic 54µg/L (19-395µg/L). Given the same age, girls in the highest quartile of urinary cadmium at 5 and 10 years of age had a lower rate of menarche than girls in the lowest quartile, with an adjusted hazard ratio of (HR) 0.80 (95% CI: 0.62, 1.01) at 5 years of age, and 0.77 (95% CI: 0.60, 0.98) at 10 years of age. This implies that girls in the highest cadmium exposure quartile during childhood had a higher age at menarche. Comparing girls in the highest to the lowest quartile of urinary lead at 10 years of age, the former had a higher rate of menarche [adjusted HR = 1.23 (95% CI: 0.97, 1.56)], implying lower age at menarche, whereas there was no association with urinary lead at 5 years of age. Girls born to mothers in the highest quartile of erythrocyte arsenic during pregnancy were less likely to have attained menarche than girls born to mothers in the lowest quartile [adjusted HR= 0.79 (95% CI: 0.62, 0.99)]. No association was found with girls' urinary arsenic exposure. DISCUSSION: Long-term childhood cadmium exposure was associated with later menarche, whereas the associations with child lead exposure were inconclusive. Maternal exposure to arsenic, but not cadmium or lead, was associated with later menarche. https://doi.org/10.1289/EHP11121.

Medical and surgical postoperative complications after breast conservation versus mastectomy in older women with breast cancer: Swedish population-based register study of 34 139 women.

BACKGROUND: Mastectomy rates in breast cancer are higher in older patients. The aim was to compare postoperative complication rates after breast-conserving surgery (BCS) to mastectomy in women aged 70-79 and older than 80 years versus those aged 50-69 years, and to evaluate survival effects. METHODS: This population-based cohort included women aged 50 years and older with invasive breast cancer T1-3 N0-3 M0 operated on in Sweden 2008-2017. Major surgical and medical 30-day postoperative complications were assessed in adjusted logistic regression models. Overall survival was assessed in Cox models adjusted for clinical confounders, socio-economics, and comorbidity. RESULTS: Of 34 139 women, 8372 (24.5 per cent) were aged 70-79 years, 3928 (11.5 per cent) were 80 years of age or older, and 21 839 (64.0 per cent) were aged 50-69 years. Major surgical postoperative complications did not differ between age groups receiving equivalent surgery (BCS: 2.1 per cent and 2.0 per cent versus 2.1 per cent (P = 0.90); mastectomy: 4.6 per cent and 5.1 per cent versus 4.6 per cent (P = 0.49)). Major medical postoperative complications were higher in women aged >70 years than in women aged 50-69 years (BCS: 1.0 per cent and 2.3 per cent versus 0.4 per cent (P < 0.001); mastectomy: 3.1 per cent and 6.2 per cent versus 1.1 per cent (P < 0.001)), which persisted after adjustments. In women treated by mastectomy, major medical and surgical postoperative complications were associated with worse overall survival in all but the middle age group. CONCLUSION: Mastectomy has higher medical and surgical postoperative complication rates than BCS. Major medical postoperative complications increase significantly with age. Major postoperative complications are associated with worse survival after mastectomy, which should be used with caution in older women.

In breast cancer, either a bit of the breast or the whole breast is removed. Older women more often have their whole breast removed. Such larger surgery may have a higher risk of complications. Complications after surgery can lower the chances of survival. The aim of this project was to find out whether older age comes with more complications after breast surgery. The authors also wanted to know whether this has an effect on survival. This work used information on women aged 50 years and older operated on for breast cancer in Sweden from 2008 to 2017. Major surgical and medical complications after breast surgery were compared in three different age groups. In addition, death of any cause was analysed. Of 34 139 women, 8372 were 70­79 years old and 3928 were aged 80 years or older. These older women were compared to 21 839 women who were 50­69 years old. Major surgical complications did not increase with age. However, medical complications were more common in older women. Removing the whole breast gave more complications than removing only part of the breast. In women aged 80 years or older who had their whole breast removed, complications after surgery increased the risk of death. This was true even when considering how severe the cancer was, how it was treated, and also what kind of socio-economic background and afflictions other than breast cancer the women had. Therefore, removal of the whole breast should be done with caution in older women.

Age-specific survival trends and life-years lost in women with breast cancer 1990-2016: the NORDCAN survival studies.

BACKGROUND: A recent overview of cancer survival trends 1990-2016 in the Nordic countries reported continued improvements in age-standardized breast cancer survival among women. The aim was to estimate age-specific survival trends over calendar time, including life-years lost, to evaluate if improvements have benefited patients across all ages in the Nordic countries. METHODS: Data on breast cancers diagnosed 1990-2016 in Denmark, Finland, Iceland, Norway, and Sweden were obtained from the NORDCAN database. Age-standardized and age-specific relative survival (RS) was estimated using flexible parametric models, as was reference-adjusted crude probabilities of death and life-years lost. RESULTS: Age-standardized period estimates of 5-year RS in women diagnosed with breast cancer ranged from 87% to 90% and 10-year RS from 74% to 85%. Ten-year RS increased with 15-18 percentage points from 1990 to 2016, except in Sweden (+9 percentage points) which had the highest survival in 1990. The largest improvements were observed in Denmark, where a previous survival disadvantage diminished. Most recent 5-year crude probabilities of cancer death ranged from 9% (Finland, Sweden) to 12% (Denmark, Iceland), and life-years lost from 3.3 years (Finland) to 4.6 years (Denmark). Although survival improvements were consistent across different ages, women aged ≥70 years had the lowest RS in all countries. Period estimates of 5-year RS were 94-95% in age 55 years and 84-89% in age 75 years, while 10-year RS were 88-91% in age 55 years and 69-84% in age 75 years. Women aged 40 years lost on average 11.0-13.8 years, while women lost 3.8-6.0 years if aged 55 and 1.9-3.5 years if aged 75 years. CONCLUSIONS: Survival for Nordic women with breast cancer improved from 1990 to 2016 in all age groups, albeit with larger country variation among older women where survival was also lower. Women over 70 years of age have not had the same survival improvement as women of younger age.

Pregnancy and childbirth outcomes in women with myeloproliferative neoplasms-a nationwide population-based study of 342 pregnancies in Sweden.

Pregnancy and childbirth in women with myeloproliferative neoplasms (MPN) are reported to be associated with maternal thrombosis, hemorrhage, and placental dysfunction. To assess the risks of adverse events in pregnancy in women with MPN, we performed a large population-based study using Swedish health care registers, and included all pregnancies that had reached gestational week 22 (prior to 2008, week 28) during the years 1973-2017 in women with MPN. Control pregnancies were matched 1:1 for age, calendar year, and parity. We identified 342 pregnancies in 229 women with MPN. Preterm birth was significantly increased in pregnancies in MPN, 14% compared to 4% of pregnancies in controls (p < 0.001). Correspondingly, low birth weight (<2500 g) was also significantly increased in MPN pregnancies (p = 0.042). Stillbirth was rare, with two events (0.6%) in MPN, none in controls. Maternal thrombotic complications occurred in three (1%) of the pregnancies in MPN patients, compared to none in controls. Pregnancy-related bleeding affected 14% of pregnancies in MPN and 9% in controls (p < 0.110). Cesarean section was significantly more common in pregnancies in MPN. Incidence was 12.2 per 100.000 pregnancies. In summary, preterm birth was an important complication in MPN pregnancies, while maternal complications were less common than previously reported.

Major surgical postoperative complications and survival in breast cancer: Swedish population-based register study in 57 152 women.

BACKGROUND: Postoperative complications may activate prometastatic systemic pathways through tissue damage, wound healing, infection, and inflammation. Postoperative complications are associated with inferior survival in several types of cancer. The aim was to determine the association between postoperative complications and survival in breast cancer. METHODS: This population-based cohort included women operated for T1-3 N0-3 M0 invasive breast cancer in Sweden from 2008 to 2017. Only major surgical postoperative complications leading to readmission and/or reoperation within 30 days were considered. Main outcomes were overall survival (OS) and breast cancer-specific survival (BCSS). Prospectively collected nationwide register data were used. Multivariable Cox models were adjusted for clinical and socioeconomic confounders and co-morbidity. RESULTS: Among 57 152 women, major surgical postoperative complications were registered for 1854 patients. Median follow-up was 6.22 (0.09-11.70) years. Overall, 9163 patients died, and 3472 died from breast cancer. Major surgical postoperative complications were more common after mastectomy with or without immediate reconstruction (7.3 and 4.3 per cent respectively) than after breast-conserving surgery (2.3 per cent). Unadjusted 5-year OS and BCSS rates were 82.6 (95 per cent c.i. 80.8 to 84.5) and 92.1 (90.8 to 93.5) per cent respectively for women with a major surgical postoperative complication, and 88.8 (88.6 to 89.1) and 95.0 (94.8 to 95.2) per cent for those without a complication (P < 0.001). After adjustment, all-cause and breast cancer mortality rates remained higher after a major surgical postoperative complication (OS: HR 1.32, 95 per cent c.i. 1.15 to 1.51; BCSS: HR 1.31, 1.04 to 1.65). After stratification for type of breast surgery, this association remained significant only for women who had mastectomy without reconstruction (OS: HR 1.41, 1.20 to 1.66; BCSS: HR 1.36, 1.03 to 1.79). CONCLUSION: Major surgical postoperative complications are associated with inferior survival, especially after mastectomy. These results underline the importance of surgical de-escalation.

Long-term outcomes of implant-based immediate breast reconstruction with and without radiotherapy: a population-based study.

BACKGROUND: Radiotherapy (RT) is a risk factor for impaired outcomes after implant-based immediate breast reconstruction (IBR). Large studies including long-term follow-up are relatively scarce. The purpose of this analysis was to assess long-term effects of RT in implant-based IBR, distinguishing between implant removal because of postoperative complications versus patient preference. METHODS: This population-based cohort study included all patients with breast cancer who underwent implant-based IBR in Stockholm between 2005 and 2015. Data were collected through national registers and medical charts. The main endpoint was implant removal owing to postoperative complications (wound breakdown, infection, bleeding) or patient preference (dissatisfaction, pain, capsular contracture), with or without conversion to autologous reconstruction. RESULTS: Some 1749 implant-based IBRs in 1687 women were included. Median follow-up was 72 (range 1-198) months. Reconstructions were divided according to receipt of RT: No RT (n = 856, 48.9 per cent), adjuvant RT (n = 749, 42.8 per cent), and previous RT (n = 144, 8.2 per cent). Implant removal occurred after 266 reconstructions (15.2 per cent); 68 (7.9 per cent) in the no RT, 158 (21.1 per cent) in the adjuvant RT, and 40 (27.8 per cent) in the previous RT group. Implant removal was because of postoperative complications in 152 instances (57.1 per cent) and was most common in the first 3 years. This was especially observed in the previous RT group, where 15 of 23 implant removals occurred during the first 6 months. Implant removal owing to patient preference (114 of 266, 42.9 per cent) became more common with increasing follow-up. CONCLUSION: Implant removal after implant-based IBR is significantly associated with RT. The reason for implant removal shifts over time from postoperative complications to patient preference.

Irradiation of the chest wall after breast removal and implant placement (reconstruction) increases the risk of complications. These may lead to removal of the implant. Some women then choose a new breast reconstruction without an implant. The aim of this project was to find out how much irradiation affects complications after breast reconstruction using implants. This work used information on women who had a breast reconstruction with implants in Stockholm, Sweden, from 2005 to 2015. The main focus was on removal of the implant. This could be due to complications or patient preference. Implant removal could be with or without a new breast reconstruction. Of 1749 reconstructed breasts in 1687 women, 266 implants were removed. This was most often because of a complication, especially in the first years after surgery, but nearly as often due to patient wish. Implant removal owing to patient wish occurred later. Irradiation was a major factor increasing the risk of implant removal, together with, for example, smoking and obesity.

Survival trends in patients diagnosed with colon and rectal cancer in the nordic countries 1990-2016: The NORDCAN survival studies.

BACKGROUND: Survival of patients with colon and rectal cancer has improved in all Nordic countries during the past decades. The aim of this study was to further assess survival trends in patients with colon and rectal cancer in the Nordic countries by age at diagnosis and to present additional survival measures. METHODS: Data on colon and rectal cancer cases diagnosed in the Nordic countries between 1990 and 2016 were obtained from the NORDCAN database. Relative survival was estimated using flexible parametric models. Both age-standardized and age-specific measures for women and men were estimated from the models, as well as reference-adjusted crude probabilities of death and life-years lost. RESULTS: The five-year age-standardized relative survival of colon and rectal cancer patients continued to improve for women and men in all Nordic countries, from around 50% in 1990 to about 70% at the end of the study period. In general, survival was similar across age and sex. The largest improvement was seen for Danish men and women with rectal cancer, from 41% to 69% and from 43% to 71%, respectively. The age-standardized and reference-adjusted five-year crude probability of death in colon cancer ranged from 30% to 36% across countries, and for rectal cancer from 20% to 33%. The average number of age-standardized and reference-adjusted life-years lost ranged between six and nine years. CONCLUSION: There were substantial improvements in colon and rectal cancer survival in all Nordic countries 1990-2016. Of special note is that the previously observed survival disadvantage in Denmark is no longer present.