Are male immigrants in Denmark at lower or higher risk of tobacco-related cancers? A Danish nationwide cohort study

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.

Increased Incidence and Mortality of Gastric Cancer in Immigrant Populations from High to Low Regions of Incidence: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Gastric cancer is the leading cause of infection-related cancer death and the third-leading cause of cancer death worldwide. The effect of immigration on gastric cancer risk is not well-defined but might be helpful for screening or surveillance endeavors. We performed a systematic review and meta-analysis to define the risk of gastric cancer in immigrants from high-incidence regions to low-incidence regions (including Western Europe, Australia, Brazil, Canada, Israel, and the United States).

METHODS

We searched MEDLINE and EMBASE databases, from January 1980 to January 2019, for studies that identified immigrants from high-incidence regions of gastric cancer, provided clear definitions of immigrant and reference populations, and provided sufficient data to calculate gastric cancer incidence and gastric cancer-related mortality. We performed meta-analyses of standardized incidence ratios (SIR) for first-generation immigrants from high- to low-incidence regions, stratified by immigrant generation, sex, and anatomic and histologic subtype, when data were available.

RESULTS

We identified 38 cohort studies that met our inclusion criteria. All 13 studies of 21 distinct populations reported significantly increased SIRs for gastric cancer in first-generation foreign-born immigrants (men SIR range, 1.24-4.50 and women SIR range, 1.27-5.05). The pooled SIR for immigrants with all types of gastric cancer was 1.66 (95% CI, 1.52-1.80) for men and 1.83 (95% CI, 1.69-1.98) for women. Nine studies from 2 high-incidence populations (the former Soviet Union and Japan) reported an increased gastric cancer standardized mortality ratio in first-generation immigrants who migrated to regions of low incidence (former Soviet Union immigrants, 1.44-1.91 for men and 1.40-2.56 for women).

CONCLUSIONS

Immigrants from regions with a high incidence of gastric cancer to regions of low incidence maintain a higher risk of gastric cancer and related mortality, based on a comprehensive systematic review and meta-analysis. Assessment of immigrant generation along with other risk factors might help identify high-risk populations for prevention and therapeutic interventions.

Cancer diagnosis and care among rural-to-urban migrants in China

Introduction

Cancer is a leading cause of death in China. Rural-to-urban migrants are a group of over 260 million people in China sometimes termed the 'floating' population. This study assessed the prevalence of cancer diagnosis and access to needed healthcare by residence and migration status in China.

Methods

We used data from the China Health and Retirement Longitudinal Survey, a nationally representative population-based random sample of adults age 45 years and older and their spouses in China. We used multivariable logistic regressions to compare outcomes among rural-to-urban migrants, local urban residents and local rural residents after adjusting for province of residence, socioeconomic status and demographic characteristics.

Results

The sample included 7335 urban residents, 9286 rural residents and 3255 rural-to-urban migrants. Prevalence of cancer diagnosis was 9.9 per 1000 population among rural-to-urban migrants (95% CI 6.5 to 15.1 per 1000 population). Rural-to-urban migrants had higher tobacco use (OR=2.01; 95% CI 1.59 to 2.56, p<0.001), lower use of a health check-up (OR=0.57; 95% CI 0.48 to 0.67, p<0.001) and lower prevalence of diagnosed cancer (OR=0.41; 95% CI 0.18 to 0.95, p=0.037) than urban residents. Among participants with diagnosed cancer, residence and migration status were not predictive of foregoing needed healthcare, but were predictive of diagnosis with a screen-detectable tumour (ie, breast, colon, prostate or cervical cancer) (OR=0.17; 95% CI 0.05 to 0.63, p=0.007 for rural residents; OR=0.34; 95% CI 0.09 to 1.22, p=0.098 for rural-to-urban migrants, compared with urban residents).

Conclusion

Rapid and large migration is still a driving force transitioning China. Due to some remaining dual policy settings in favour of local residents, rural migrants tend to use lower primary care and preventive health check-ups in general, and diagnosis of screen-detectable tumours in particular, leading to potentially higher risk of missing early diagnosis of cancers. Closing gaps in diagnosis of screen-detectable tumours could increase treatment and improve cancer outcomes.