Prognostic factors and disease-specific survival among immigrants diagnosed with cutaneous malignant melanoma in Sweden

Cancer survival is an important indicator for quality of cancer care. We sought to determine if there are differences in cancer survival between immigrants and the host population in Norway. We performed a nationwide registry-based study comprising subjects diagnosed with cancer between 1990 and 2014, and followed until the end of 2016. Survival was estimated for 13 cancer sites with cause-specific survival. Adjustments were made for common confounders (age, sex, year of diagnosis and place of residence) and defined mediators (stage at diagnosis, comorbidity and socioeconomic factors). A total of 500,255 subjects were available for analysis, of which 11,252 were Western and 8,701 non-Western immigrants. We did not find differences in cancer survival between Western immigrants and Norwegians, while non-Western immigrants, with some exceptions, had similar or better survival. Better lung cancer survival in non-Western immigrants than Norwegians was notable (hazard ratio (95% confidence interval): 0.78 (0.71-0.85)), and not explained by defined mediators. Immigrants from Eastern Europe and Balkan with melanoma (hazard ratio: 1.54 (1.12-2.12)) and prostate cancer (hazard ratio: 1.34 (1.08-1.67)), and possibly from sub-Saharan Africa with breast cancer (hazard ratio: 1.41 (0.94-2.12)) had worse survival than Norwegians. The results suggest that immigrants in Norway have good cancer survival relative to the host population. Poor survival in immigrants from Eastern Europe and Balkan with melanoma and prostate cancer, and sub-Saharan Africa with breast cancer might be a concern.

Section: Discussioncontrasting

confidence: 56%

“…[11][12][13][14][15][16] A few Nordic studies have reported worse survival in immigrants with breast cancer and melanoma relative to the host populations. [17][18][19] The purpose of this study was to describe cancer survival for immigrants in Norway across 13 common cancer sites.…”

mentioning

confidence: 99%

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

Thøgersen

Møller

Robsahm

et al. 2018

“…21 Potential regional effects due to referral of severe cases to Stockholm can be excluded, since only residents of the Stockholm region are reported to the SMR, while an effect of an increased proportion of immigrant patients with later stage at diagnosis, and worse outcome, cannot be excluded. 23 Median age at diagnosis was 62.9 years, which is higher than what has been observed in previous international studies. 21,24,25 However, more recent Swedish studies report comparable figures.…”

Section: Cancer Epidemiologycontrasting

confidence: 52%

“…Higher proportions of patients diagnosed with advanced disease in this study could be due to more extensive investigations and more efficient detection of subclinical metastatic disease, or a higher number of thick melanoma tumors, which has been reported in Sweden over the past years . Potential regional effects due to referral of severe cases to Stockholm can be excluded, since only residents of the Stockholm region are reported to the SMR, while an effect of an increased proportion of immigrant patients with later stage at diagnosis, and worse outcome, cannot be excluded …”

Section: Discussionmentioning

confidence: 99%

Epidemiology of cutaneous melanoma in Sweden—Stage‐specific survival and rate of recurrence

Rockberg¹,

Amelio

Taylor

et al. 2016

Self Cite

Cutaneous malignant melanoma (CMM) incidence is increasing globally, making a thorough understanding of the disease and its outcomes essential for optimizing care even more urgent. In this population-based, retrospective study, we investigated stage-specific survival and recurrence/progression rates of CMM among patients diagnosed in Stockholm County Council during 2005-2012, before the wide introduction of targeted therapy. A total of 3,554 CMM patients from the Stockholm Melanoma Register were included. Information on comorbidities, progression, death, and treatments was obtained from nationwide registers and hospital electronic medical records. Unadjusted 5-year survival varied from 91.4% for stage I to 24.6% for stage IV patients. Stage, age and gender were predictors of survival, with gender an independent predictor of survival for stages IA and IIA. 74.6% of patients remained recurrence/progression-free during follow-up, with 5-year recurrence/progression-free survival rates varying from 85.3% to 12.9% among stages I and IV patients, respectively. In addition to stage, male gender, and age, circulatory system comorbidities increased the risk for recurrence/progression. No statistically significant differences in progression rate for operated and non-operated patients could be detected, possibly due to high rate (98.9%) of surgery. Our estimates of survival and recurrence rates are consistent with historical and global expectations and can serve as a baseline to gauge population-level improvements with use of novel melanoma treatments.

“…A Danish study included several cancer sites in women and reported that immigrants had a slightly higher risk of being diagnosed at a more advanced stage than the host population . Similar results were also reported in a Swedish study on malignant melanoma . Although some research has pointed towards later detection of cancer in immigrant populations in Europe, detailed information, both for various immigrant groups and several cancer sites, is missing.…”

mentioning

confidence: 55%

Comparison of cancer stage distribution in the immigrant and host populations of Norway, 1990–2014

Thøgersen

Møller

Robsahm

et al. 2017

Cancer stage at diagnosis is the most important prognostic factor for survival. We conducted a nationwide, population-based cohort study to investigate cancer stage distribution in immigrants compared to the host population of Norway. All patients recorded in the Cancer Registry of Norway in 1990-2014 were included (17,709 immigrants and 431,936 Norwegians). Individual level sociodemographic data was obtained from Statistics Norway. Ordered logistic regression was used to estimate if immigrants were diagnosed with cancer at a more advanced stage than Norwegians. Seven cancer sites were analyzed (breast, cervix, colorectal, liver, lung and trachea, prostate and stomach). With exception of breast cancer, we did not observe a clear pattern of more advanced cancer stage distribution in immigrants compared to Norwegians. Odds ratios and corresponding 95% confidence intervals for being diagnosed with a more advanced stage of breast cancer for non-Western immigrant groups compared to Norwegians were: Eastern Europe: 1.41 (1.20-1.65), Middle East: 1.58 (1.19-2.10), sub-Saharan Africa: 1.44 (0.99-2.08), South Asia: 1.40 (1.07-1.83) and East Asia: 0.90 (0.72-1.13). Sub-analyses showed that late detection of breast cancer in young non-Western immigrants might be of particular concern. Young (<50 years) non-Western immigrants had an odds ratio of 1.40 (1.21-1.62) for more advanced stage breast cancer compared to young Norwegians.