Background We previously observed decreasing resection rates of non-metastatic gastric adenocarcinoma (GaC) in the US and some European countries. If and to what extent these trends affect the... Show moreBackground We previously observed decreasing resection rates of non-metastatic gastric adenocarcinoma (GaC) in the US and some European countries. If and to what extent these trends affect the trends in overall survival (OS) of patients with non-metastatic GaC at the population level remain unclear. This large international population-based cohort study aimed to assess the impact of the previously observed decreasing resection rates on multivariable-adjusted trends in the long-term OS of patients with non-metastatic GaC. Methods Individual-level data of patients with non-metastatic GaC were obtained from the national cancer registries of the Netherlands, Belgium, Sweden, Norway, and Slovenia, and the US Surveillance, Epidemiology, and End Results database. We analyzed data for each country separately. Associations between year of diagnosis and OS were assessed using Cox proportional hazards regression model with adjustment for multiple prognostic variables, with and without including resection and chemotherapy as potential explanatory variables. Results A total of 66,398 non-metastatic GaC patients diagnosed in 2003-2016 were analyzed, with an accumulated follow-up of 172,357 person-years. Without adjustment for resection, OS was improved only slightly in the US [hazard ratio (HR)(per year) = 0.99; HR >= (vs.) (<2010) = 0.96], and no improvement was observed in the investigated European countries, with OS even worsening in Sweden (HRper year = 1.03; HR >= (vs.) (<2010) = 1.17). After adjusting for resection, the increasing OS trend became stronger in the US (HRper year = 0.98; HR >= (vs.) (<2010) = 0.88), and the temporal trend became insignificant in Sweden. In Slovenia (HRper year = 0.99; HR >= (vs.) (<2010) = 0.92) and Norway (HRper year = 0.97; HR >= (vs.) (<2010) = 0.86), improved OS over time emerged after resection adjustment. Improved OS in patients undergoing resection was observed in the US, the Netherlands, and Norway. Adjustment for chemotherapy did not alter the observed associations. Stratified analyses by tumor location showed mostly similar results with the findings in all patients with non-metastatic GaCs regarding the associations between year of diagnosis and survival. Conclusions OS of patients with non-metastatic GaC mostly did not improve in selected European countries and was even worsened in Sweden, while it was slightly increased in the US in the early 21(st) century. Progress in OS of patients with non-metastatic GaC seems to have been impeded to a large extent by decreasing rates of resection. Show less
Bastiaannet, E.; Charman, J.; Johannesen, T.B.; Schrodi, S.; Siesling, S.; Eycken, L. van; ... ; Velde, C.J.H. van de 2018
Over 40% of breast cancer patients are diagnosed above the age of 65. Treatment of these elderly patients will probably vary over countries. The aim of this study was to make an international... Show moreOver 40% of breast cancer patients are diagnosed above the age of 65. Treatment of these elderly patients will probably vary over countries. The aim of this study was to make an international comparison (several European countries and the US) of surgical and radiation treatment for elderly women with early stage breast cancer. Survival comparisons were also made. Data were obtained from national or regional population-based registries in the Netherlands, Switzerland, Ireland, Belgium, Germany, and Portugal. For the US patients were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Early stage breast cancer patients aged ≥65 diagnosed between 1995 and 2005 were included. An international comparison was made for breast and axillary surgery, radiotherapy after breast conserving surgery (BCS), and relative or cause-specific survival. Overall, 204.885 patients were included. The proportion of patients not receiving any surgery increased with age in many countries; however, differences between countries were large. In most countries more than half of all elderly patients received breast conserving surgery (BCS), with the highest percentage in Switzerland. The proportion of elderly patients that received radiotherapy after BCS decreased with age in all countries. Moreover, in all countries the proportion of patients who do not receive axillary surgery increased with age. No large differences in survival between countries were recorded. International comparisons of surgical treatment for elderly women with early stage breast cancer are scarce. This study showed large international differences in treatment of elderly early stage breast cancer patients, with the most striking result the large proportion of elderly who did not undergo surgery at all. Despite large treatment differences, survival does not seem to be affected in a major way. Show less
