No evidence to support the impact of migration background on treatment response rates and cancer survival: a retrospective matched-pair analysis in Germany.

BACKGROUND: Immigration has taken the central stage in world politics, especially in the developed countries like Germany, where the continuous flow of immigrants has been well documented since 1960s. Strikingly, emerging data suggest that migrant patients have a poorer response to the treatment and lower survival rates in their new host country, raising concerns about health disparities. Herein, we present our investigation on the treatment response rate and cancer survival in German patients with and without an immigrant background that were treated at our comprehensive cancer center in Germany. METHODS: Initially, we considered 8162 cancer patients treated at the Center for Integrated Oncology (CIO), University Hospital Bonn, Germany (April 2002-December 2015) for matched-pair analysis. Subsequently, the German patients with a migration background and those from the native German population were manually identified and catalogued using a highly specific name-based algorithm. The clinical parameters such as demographic characteristics, tumor characteristics, defined staging criteria, and primary therapy were further adjusted. Using these stringent criteria, a total of 422 patients (n = 211, Germans with migration background; n = 211, native German population) were screened to compare for the treatment response and survival rates (i.e., 5-year overall survival, progression-free survival, and time to progression). RESULTS: Compared to the cohort with migration background, the cohort without migration background was slightly older (54.9 vs. 57.9 years) while having the same sex distribution (54.5% vs. 55.0% female) and longer follow-up time (36.9 vs. 42.6 months). We did not find significant differences in cancer survival (5-year overall survival, P = 0.771) and the response rates (Overall Remission Rate; McNemar's test, P = 0.346) between both collectives. CONCLUSION: Contrary to prior reports, we found no significant differences in cancer survival between German patients with immigrant background and native German patients. Nevertheless, the advanced treatment protocols implemented at our comprehensive cancer center may possibly account for the low variance in outcome. To conduct similar studies with a broader perspective, we propose that certain risk factors (country-of-origin-specific infections, dietary habits, epigenetics for chronic diseases etc.) should be considered, specially in the future studies that will recruit new arrivals from the 2015 German refugee crisis.

A matched-pair analysis on survival and response rates between German and non-German cancer patients treated at a Comprehensive Cancer Center.

BACKGROUND: Research shows disparities in cancer outcomes by ethnicity or socio-economic status. Therefore, it is the aim of our study to perform a matched-pair analysis which compares the outcome of German and non-German (in the following described as 'foreign') cancer patients being treated at the Center for Integrated Oncology (CIO) Köln Bonn at the University Hospital of Bonn between January 2010 and June 2016. METHODS: During this time, 6314 well-documented patients received a diagnosis of cancer. Out of these patients, 219 patients with foreign nationality could be matched to German patients based on diagnostic and demographic criteria and were included in the study. All of these 438 patients were well characterized concerning survival data (Overall survival, Progression-free survival and Time to progression) and response to treatment. RESULTS: No significant differences regarding the patients' survival and response rates were seen when all German and foreign patients were compared. A subgroup analysis of German and foreign patients with head and neck cancer revealed a significantly longer progression-free survival for the German patients. Differences in response to treatment could not be found in this subgroup analysis. CONCLUSIONS: In summary, no major differences in survival and response rates of German and foreign cancer patients were revealed in this study. Nevertheless, the differences in progression-free survival, which could be found in the subgroup analysis of patients with head and neck cancer, should lead to further research, especially evaluating the role of infectious diseases like human papillomavirus (HPV) and Epstein-Barr virus (EBV) on carcinogenesis and disease progression.