Differences in cancer survival between immigrants in Norway and the host population

Lung cancer survival by immigrant status: a population-based retrospective cohort study in Ontario, Canada

BACKGROUND

Lung cancer is one of the most common cancers and causes of cancer death in Canada. Some previous literature suggests that socioeconomic inequalities in lung cancer screening, treatment and survival may exist. The objective of this study was to compare overall survival for immigrants versus long-term residents of Ontario, Canada among patients diagnosed with lung cancer.

METHODS

This population-based retrospective cohort study utilized linked health administrative databases and identified all individuals (immigrants and long-term residents) aged 40 + years diagnosed with incident lung cancer between April 1, 2012 and March 31, 2017. The primary outcome was 5-year overall survival with December 31, 2019 as the end of the follow-up period. We implemented adjusted Cox proportional hazards models stratified by age at diagnosis, sex, and cancer stage at diagnosis to examine survival.

RESULTS

Thirty-eight thousand seven hundred eighty-eight individuals diagnosed with lung cancer were included in our cohort including 7% who were immigrants. Immigrants were younger at diagnosis and were more likely to reside in the lowest neighbourhood income quintile (30.6% versus 24.5%) than long-term residents. After adjusting for age at diagnosis, neighbourhood income quintile, comorbidities, visits to primary care in the 6 to 30 months before diagnosis, continuity of care, cancer type and cancer stage at diagnosis, immigrant status was associated with a lower hazard of dying 5-years post-diagnosis for both females (0.7; 95% CI 0.6-0.8) and males (0.7; 95% CI 0.6-0.7) in comparison to long-term residents. This trend held in adjusted models stratified by cancer stage at diagnosis. For example, female immigrants diagnosed with early stage lung cancer had a hazard ratio of 0.5 (95% CI 0.4-0.7) in comparison to long-term residents.

CONCLUSION

Overall survival post diagnosis with lung cancer was better among Ontario immigrants versus long-term residents. Additional research, potentially on the protective effects of immigrant enclave and the intersection of immigrant status with racial/ethnic identity, is needed to further explore why better overall survival for immigrants remained.

Breast cancer-specific survival among immigrants and non-immigrants invited to BreastScreen Norway

Introduction

We have previously shown that immigrants have lower attendance in BreastScreen Norway than non-immigrants and that non-Western immigrants have lower incidence of breast cancer, but more advanced disease.

Purpose

To compare breast cancer-specific survival for immigrants versus non-immigrants diagnosed with screen-detected or symptomatic breast cancer.

Material and methods

We analyzed data from 28,320 women aged 50-69 diagnosed with breast cancer after being invited to BreastScreen Norway. We divided women into three groups; non-immigrants, immigrants from Western countries and immigrants from non-Western countries. We stratified our analyses according to detection mode (screen-detected breast cancer, interval cancer and cancer detected outside screening), and used cox regression to model the association between immigrants/non-immigrants and time to breast cancer death.

Results

Among screen-detected breast cancers, 28.7% were histologic grade 3 among immigrants from non-Western countries compared to 21.3% among non-immigrants. Interval cancers and cancers detected outside screening had larger tumor diameter and a higher percentage were histologic grade 3 and lymph node positive among immigrants from non-Western countries compared to non-immigrants. Hazard ratio (95% confidence interval) adjusted for age and year of diagnosis for time to breast cancer death compared to non-immigrants was 0.70 (0.39-1.27) for immigrants from Western countries and 0.52 (0.23-1.17) for immigrants from non-Western countries.

Conclusion

Despite more advanced histopathological tumor characteristics among immigrants from non-Western countries compared to non-immigrants, we did not observe statistically significant differences in breast-cancer specific survival between the two groups. Keeping in mind the low number of breast cancer deaths and possible overestimation of survival among immigrants, this might imply that equity in outcome can be achieved through adequate follow-up and treatment despite inequal access.

Impact of Prostate Cancer in Eastern Europe and Approaches to Treatment and Policy

Prostate cancer is among the most prevalent cancer globally and within Eastern Europe, where there are also higher levels of mortality compared with Western Europe. Cancer control plans exist in most countries in the region. Attention should be given to devising and implementing optimal screening initiatives. Our review has identified that a lack of resources and health system dysfunctions hamper progress in ameliorating the burden of prostate cancer. Regional cooperation is needed as well as drawing on guidelines and findings from elsewhere. Health institutions must also know the latest developments and set up systems that allow swift adoption.

Educational disparities in cancer incidence, stage, and survival in Oslo

OBJECTIVES

This study aimed to examine disparities in cancer incidence, stage at diagnosis, and survival rates across districts with differences in education levels in Oslo, Norway.

METHODS

Aggregated data from the Cancer Registry of Norway in the period 2013-2021 were used to describe the distribution of cancer incidence and survival across Oslo's 15 administrative districts, subsequently grouped into three areas based on the population's level of education. Age-standardised incidence rates and five-year relative survival were calculated for colon, rectal, lung, melanoma, breast, and prostate cancer. The stage at the time of diagnosis was categorised as localised, regional, distant, and unknown for all cancer types except breast cancer, which was categorised into stage I-IV and unknown.

RESULTS

Mid- and high-education areas had higher incidences of breast, melanoma, and prostate cancer, while the low-education area had higher incidence rates for lung cancer. The low-education area had a higher proportion diagnosed at a distant stage than the other groups for all cancer types studied, except breast cancer. The mid- and high-education areas had higher five-year relative survival rates overall.

CONCLUSIONS

Incidence, stage at diagnosis, and survival varied between education areas. The variation indicates disparities in healthcare access, quality of care, and health behaviours. Addressing these disparities can help improve overall health outcomes and promote health equity.

Lower participation among immigrants in colorectal cancer screening in Norway

Introduction

Organized cancer screening programs should be equally accessible for all groups in society. We assessed differences in participation in colorectal cancer (CRC) screening among different immigrant groups.

Methods

Between 2012 and 2019, 140,000 individuals aged 50 to 74 years were randomly invited to sigmoidoscopy or repeated faecal immunochemical test (FIT) in a CRC screening trial. In this study, we included 46,919 individuals invited to sigmoidoscopy and 70,018 invited to the first round of FIT between 2012 and 2017. We examined difference in participation between non-immigrants and immigrants, and within different immigrant groups by geographic area of origin, using logistic regression models, adjusted for several sociodemographic factors and health factors.

Results

In total, we included 106,695 non-immigrants and 10,242 immigrants. The participation rate for FIT was 60% among non-immigrants, 58% among immigrants from Western countries and 37% among immigrants from non-Western countries. The participation rate for sigmoidoscopy was 53% among non-immigrants, 48% among immigrants from Western countries and 23% among immigrants from non-Western countries. Compared to non-immigrants, multivariate adjusted odds ratio for non-participation in FIT screening was 1.13 (95% confidence interval 1.04-1.23) and 1.82 (1.69-1.96) for immigrants from Western and non-Western countries. The corresponding numbers in sigmoidoscopy screening were 1.34 (1.21-1.48) and 2.83 (2.55-3.14). The lowest participation was observed in immigrants from Eastern Europe, Northern Africa and Western Asia, and South-Central Asia.

Conclusion

Participation in CRC screening in Norway was particularly low among non-Western immigrants, which could put them at increased risk for late stage diagnosis of CRC. Participation was lower in sigmoidoscopy screening than in FIT screening, especially among immigrants from non-Western countries.

Impact of patient nationality on the severity of early side effects after radiotherapy

BACKGROUND

Major demographical changes in Germany commenced in the 1960s. Ongoing humanitarian crises in the Ukraine with subsequent immigration will have also long-range effects on national provision of cancer treatment. Ensuring the best possible outcomes for each cancer patient undergoing radiotherapy requires the prediction and prevention of unfavorable side effects. Given that recent research has primarily focused on clinical outcome indicators solely, less is known regarding sociodemographic predictors of therapeutic outcomes, such as patient nationality. Here, we investigated whether the severity of early side effects after radiotherapy are associated with patient nationality and other sociodemographic and clinical characteristics.

METHODS

Out of 9187 patients treated at a German university medical center between 2017 and 2021, 178 German and 178 non-German patients were selected for matched-pair analysis based on diagnostic and demographic criteria. For all 356 patients, data on side effects from follow-up care after radiotherapy were collected.

RESULTS

Non-German patients were more likely to have severe side effects than German patients. Side effect severity was also associated with tumor entity, concomitant therapy, body mass index, and age.

CONCLUSION

Foreign cancer patients are at higher risk of experiencing severe side effects of radiotherapy, suggesting a need to develop and implement targeted preventive measures for these patients. Further research investigating factors predicting the occurrence of radiotherapy side effects, including other sociodemographic characteristics, is needed to better personalize therapy regimens for cancer.

Nevus Count, Pigmentary Characteristics, and Melanoma-specific Mortality among Norwegian Women with Melanoma >1.0 mm Thick

Little is known about if and how nevi and pigmentation are associated with melanoma-specific mortality. However, increased melanoma awareness in people with lighter pigmentation and many nevi may result in earlier diagnosis of thinner less-lethal tumors. The aim of this study was to investigate associations between nevus count (asymmetrical > 5 mm and small symmetrical), pigmentary characteristics (hair colour, eye colour, skin colour, freckling, pigmentary score), and melanoma-specific mortality in subjects with melanomas > 1 mm. Data from the Norwegian Women and Cancer cohort, established in 1991, with complete follow-up of melanoma patients until 2018 through the Cancer Registry of Norway, were used to estimate hazard ratios with 95% confidence intervals for the associations between nevus count, pigmentary characteristics, and melanoma-specific mortality, stratified by tumor thickness using Cox regression. Estimated hazard ratios consistently indicated a higher risk of melanoma death for those with darker vs lighter pigmentary characteristics in patients with tumors > 1.0-2.0 mm and > 2.0 mm thick (e.g. pigmentary score hazard ratio 1.25, 95% confidence interval (0.74-2.13)). Among women with melanomas > 1.0 mm thick, lighter pigmentation and asymmetrical nevi may be associated with lower melanoma-specific mortality, suggesting that factors that increase the risk of melanoma may also be associated with decreased risk of death from melanoma.

Patterns of care and outcomes in immigrants with non-small cell lung cancer. A population-based study (Sweden)

OBJECTIVES

While studies have found lower cancer risks and better cancer survival in immigrant populations, it is debated whether cancer care is offered on equal terms to all residents regardless of background. Our aim was to study patterns of care and outcomes in immigrants in a country with a tax-financed universal health care system.

MATERIAL AND METHODS

We used a population-based database to compare clinical presentation, management and mortality between Swedish-born and immigrant patients with non-small cell lung cancer (NSCLC). Analyses were adjusted for potential confounders.

RESULTS

We identified 40,075 patients diagnosed with NSCLC of which 84% were born in Sweden, 7% in Nordic and 9% in Non-Nordic countries. Non-Nordic immigrants were to a higher extent male, smokers, younger at diagnosis, had a better performance status and a higher educational level. No differences were seen regarding comorbidity burden or stage at diagnosis. Non-Nordic immigrants more often underwent positron emission tomography (PET) (aHR 1.32; 95% CI 1.19-1.45) and were more often discussed in a multidisciplinary team setting (aHR 1.30; 95% CI 1.17-1.44). There were no differences in treatment modalities following adjustment for age, with the exception of concurrent chemoradiotherapy in stage IIIA disease which was more common in Non-Nordic immigrants (aOR 1.34; 95% CI 1.03-1.74). Both overall and cause specific survival in non-metastatic disease were higher among Non-Nordic immigrants. Overall mortality in stage I-II: HR 0.81; 95% CI 0.73-0.90 and stage IIIA: HR 0.75; 95% CI 0.65-0.86. Following full adjustments, cause-specific mortality in stage I-II was aHR 0.86, 95% CI 0.75-0.98.

CONCLUSION

Taken together, only minor differences in management and outcomes were observed between Swedish-born and immigrant patients. We conclude that lung cancer care is offered on equal terms. If anything, outcomes were better in Non-Nordic immigrants with early stage NSCLC.

Early screening outcomes among non-immigrants and immigrants targeted by BreastScreen Norway, 2010-2019

AIMS

This study aimed to analyse results on early screening outcomes, including recall and cancer rates, and histopathological tumour characteristics among non-immigrants and immigrants invited to BreastScreen Norway.

METHODS

We included information about 2, 763,230 invitations and 2,087,222 screening examinations from 805,543 women aged 50-69 years who were invited to BreastScreen Norway between 2010 and 2019. Women were stratified into three groups based on their birth country: non-immigrants, immigrants born in Western countries and immigrants born in non-Western countries. Age-adjusted regression models were used to analyse early screening outcomes. A random intercept effect was included in models where women underwent several screening examinations.

RESULTS

The overall attendance was 77.5% for non-immigrants, 68% for immigrants from Western countries and 51.5% for immigrants from non-Western countries. The rate of screen-detected cancers was 5.9/1000 screening examinations for non-immigrants, 6.3/1000 for immigrants from Western countries and 5.1/1000 for immigrants from non-Western countries. Adjusted for age, the rate did not differ statistically between the groups (p=0.091). The interval cancer rate was 1.7/1000 screening examinations for non-immigrants, 2.4/1000 for immigrants from Western countries and 1.6/1000 for non-Western countries (p<0.001). Histological grade was less favourable for screen-detected cancers, and subtype was less favourable for interval cancers among immigrants from non-Western countries versus non-immigrants.

CONCLUSIONS

There were no differences in age-adjusted rate of screen-detected cancer among non-immigrants and immigrants from Western countries or non-Western countries among women attending BreastScreen Norway between 2010 and 2019. Small but clinically relevant differences in histopathological tumour characteristics were observed between the three groups.

Mortality in first- and second-generation immigrants to Sweden diagnosed with type 2 diabetes: a 10 year nationwide cohort study

AIMS/HYPOTHESIS

Non-Western immigrants to Europe are at high risk for type 2 diabetes. In this nationwide study including incident cases of type 2 diabetes, the aim was to compare all-cause mortality (ACM) and cause-specific mortality (CSM) rates in first- and second-generation immigrants with native Swedes.

METHODS

People living in Sweden diagnosed with new-onset pharmacologically treated type 2 diabetes between 2006 and 2012 were identified through the Swedish Prescribed Drug Register. They were followed until 31 December 2016 for ACM and until 31 December 2012 for CSM. Analyses were adjusted for age at diagnosis, sex, socioeconomic status, education, treatment and region. Associations were assessed using Cox regression analysis.

RESULTS

In total, 138,085 individuals were diagnosed with type 2 diabetes between 2006 and 2012 and fulfilled inclusion criteria. Of these, 102,163 (74.0%) were native Swedes, 28,819 (20.9%) were first-generation immigrants and 7103 (5.1%) were second-generation immigrants with either one or both parents born outside Sweden. First-generation immigrants had lower ACM rate (HR 0.80 [95% CI 0.76, 0.84]) compared with native Swedes. The mortality rates were particularly low in people born in non-Western regions (0.46 [0.42, 0.50]; the Middle East, 0.41 [0.36, 0.47]; Asia, 0.53 [0.43, 0.66]; Africa, 0.47 [0.38, 0.59]; and Latin America, 0.53 [0.42, 0.68]). ACM rates decreased with older age at migration and shorter stay in Sweden. Compared with native Swedes, first-generation immigrants with ≤ 24 years in Sweden (0.55 [0.51, 0.60]) displayed lower ACM rates than those spending >24 years in Sweden (0.92 [0.87, 0.97]). Second-generation immigrants did not have better survival rates than native Swedes but rather displayed higher ACM rates for people with both parents born abroad (1.28 [1.05, 1.56]).

CONCLUSIONS/INTERPRETATION

In people with type 2 diabetes, the lower mortality rate in first-generation non-Western immigrants compared with native Swedes was reduced over time and was equalised in second-generation immigrants. These findings suggest that acculturation to Western culture may impact ACM and CSM in immigrants with type 2 diabetes but further investigation is needed. Graphical abstract.

Cancer incidence in non-immigrants and immigrants in Norway

BACKGROUND

Major cancers are associated with lifestyle, and previous studies have found that the non-immigrant populations in the Nordic countries have higher incidence rates of most cancers than the immigrant populations. However, rates are changing worldwide - so these differences may disappear with time. Here we present recent cancer incidence rates among immigrant and non-immigrant men and women in Norway and investigate whether previous differences still exist.

MATERIAL AND METHODS

We took advantage of a recent change in the Norwegian Cancer Registry regulations that allow for the registry to have information on country of birth. The number of person years for 2014-2018 was aggregated for every combination of sex, five-year age-group and country of birth, by summing up each year's population in these groups. The number of cancer cases was then counted for the same groups, and age-standardised incidence rates calculated by weighing the age-specific incidence rates by the Nordic and World standard populations. Further, we calculated incidence rate ratios using the non-immigrant population as a reference.

RESULTS

Immigrants from Eastern Europe, the Middle East, Africa and Asia had lower incidence of total cancer compared to the non-immigrant population in Norway and immigrants born in the other Nordic or high-income countries. However, some cancers were more common in certain immigrant groups. Asian men and women had threefold the incidence of liver cancer than non-immigrant men and women. Men from the other Nordic countries and from Eastern Europe had higher lung cancer rates than non-immigrant men.

CONCLUSION

National registries should continuously monitor and present cancer incidence stratified on important population subgroups such as country of birth. This can help assess population subgroup specific needs for cancer prevention and treatment, and could eventually help reduce the morbidity and mortality of cancer.

Waiting times and treatment following cancer diagnosis: comparison between immigrants and the Norwegian host population

Background: There are concerns about timely access to appropriate cancer treatment for the growing immigrant population in Norway. This study aims to compare waiting times between cancer diagnosis and start of cancer treatment, as well as treatment patterns between immigrants in Norway and the host population.Material and methods: We performed a nationwide, registry-based study with individual-level data, including 213,320 Norwegians and 8324 immigrants diagnosed with breast, colorectal, lung or prostate cancer in 1990-2014. Differences in time from diagnosis to treatment and in treatment patterns were described for the selected cancer sites. The Cox and logistic regressions were used to adjust for patient and tumour characteristics.Results: After adjustment for covariates, hazard ratios for time from diagnosis to treatment for non-Western immigrants compared to Norwegians were 0.88 (95% confidence interval (CI): 0.82-0.95) for breast cancer and 0.84 (95% CI: 0.75-0.95) for lung cancer, indicating longer waiting times. Treatment patterns in the four major cancer sites were similar among immigrants and the Norwegian host population, except for breast cancer, where women from East and South Asia received less breast-conserving surgery than the Norwegian host population (adjusted odds ratios 0.65 (95% CI: 0.46-0.93) for East Asians and 0.75 (95% CI: 0.50-1.13) for South Asians).Conclusions: The present study reports delayed treatment for lung and breast cancer among immigrants from non-Western countries in Norway. Systematic differences in cancer treatment were not detected. However, less breast-conserving surgery among breast cancer patients from Asia compared to Norwegians was observed.