As a result of our ageing population, breast cancer is becoming a disease of the elderly. Unfortunately, most studies investigating the efficacy of treatment do not include older patients and are... Show moreAs a result of our ageing population, breast cancer is becoming a disease of the elderly. Unfortunately, most studies investigating the efficacy of treatment do not include older patients and are not representative for the older population. In this thesis, we investigated whether there is variation in treatment and survival among older women with breast cancer in five European countries. Moreover, we study the long term efficacy of two types of adjuvant endocrine therapy in postmenopausal women. In addition, the effect of age and comorbidities on breast cancer death in the presence of competing mortality is studied. Finally, we investigate whether other endpoints in clinical studies might be more relevant for the older population and we introduce a new endpoint for clinical research in the older population with cancer. Show less
Older women with breast cancer are underrepresented in the available evidence. Therefore, there is no solid evidence on how to treat older women with breast cancer. This thesis has three main... Show moreOlder women with breast cancer are underrepresented in the available evidence. Therefore, there is no solid evidence on how to treat older women with breast cancer. This thesis has three main conclusions: 1. There are large international differences in the treatment strategy of breast cancer among older women. These differences are not associated with a significant difference in prognosis. 2. The presence of comorbidity has an important impact on the general prognosis of older women with breast cancer. We did not show an important association between specific comorbidities or the use of co-medications and the breast cancer specific prognosis. 3. Concerning older women with breast cancer for research, there are very important methodological issues to take into account, including to avoidance of selection bias and the proper methodologies to take in to account the chance of dying from another cause of cancer: the competing risk of mortality. Future research should be done to create a tool which can assist in identifying the individualised treatment strategy for each older woman with breast cancer. This will have to take into consideration patient’s and tumour’s information, as well as the endpoints for each individual patient. Show less
