RESUMEN
BACKGROUND: Few studies have investigated socioeconomic inequalities within cities. Yet, such analyses are particularly important given the increasing international trend to urbanization. Here we investigated area-based socioeconomic inequalities in cancer survival in Hamburg, a port city in the North of Germany (population: 1.84 million people). METHODS: Patients with a diagnosis of colorectal, lung, female breast, and prostate cancer in 2004-2018 (follow-up until 31.12.2018) and registered in the Hamburg cancer registry were included. Area-based socioeconomic deprivation on urban district level was assigned to the patients and grouped in five quintiles. Relative survival in 2014-2018 was calculated using the period approach. Trend analyses between 2004 and 2018 were conducted. Relative excess risks adjusted for age and stage were computed with model-based period analyses. FINDINGS: For the 73,106 included patients, age-standardized 5-year relative survival in 2014-2018 decreased with increasing deprivation with significant differences between the most and least deprived group of 14·7 (prostate), 10·8 (colorectal), 8·0 (breast), and 2·5 (lung) percent units. Standardization by cancer stage decreased the difference for prostate cancer to 8·5 percent units and for breast cancer to 3·6 percent units but had only a minor effect for colorectal and lung cancer. Similar socioeconomic inequalities were already present in 2004-08. INTERPRETATION: Strong socioeconomic inequalities in cancer survival were observed in Hamburg, which could be partly explained by differences in the stage distribution. Further research including information on screening participation as well as information on cancer care are important to further understand and finally overcome these inequalities. FUNDING: German Cancer Aid.
RESUMEN
Many countries have reported survival inequalities due to regional socioeconomic deprivation. To quantify the potential gain from eliminating cancer survival disadvantages associated with area-based deprivation in Germany, we calculated the number of avoidable excess deaths. We used population-based cancer registry data from 11 of 16 German federal states. Patients aged ≥15 years diagnosed with an invasive malignant tumor between 2008 and 2017 were included. Area-based socioeconomic deprivation was assessed using the quintiles of the German Index of Multiple Deprivation (GIMD) 2010 on a municipality level nationwide. Five-year age-standardized relative survival for 25 most common cancer sites and for total cancer were calculated using period analysis. Incidence and number of avoidable excess deaths in Germany in 2013-2016 were estimated. Summed over the 25 cancer sites, 4100 annual excess deaths (3.0% of all excess deaths) could have been avoided each year in Germany during the period 2013-2016 if relative survival were in all regions comparable with the least deprived regions. Colorectal, oral and pharynx, prostate, and bladder cancer contributed the largest numbers of avoidable excess deaths. Our results provide a good basis to estimate the potential of intervention programs for reducing socioeconomic inequalities in cancer burden in Germany.