PhD defence M.S. (Melinda) Schuurman

Below is a brief summary of the dissertation:

This thesis focuses on trends in incidence, treatment, and outcomes, such as survival and postoperative mortality, among older cancer patients in the Netherlands. Several tumor types were examined as well as the broader population of patients aged 80 years and older. Although cancer occurs most frequently at an older age, older individuals are less often included in clinical studies on which treatment guidelines are based. Moreover, the elderly who do participate often do not represent the broader population adequately. Older patients are more likely to have comorbidities, poorer performance status, and shorter life expectancy, which call for different considerations and care needs. The result show that older patients receive less intensive treatment than younger patients. They also make less use of new (systemic) therapies, such as targeted agents and immunotherapy. This may contribute to a widening survival gap between age groups. For several cancer types, there has been an increasing tendency over time toward a watchful waiting approach or refraining from cancer-directed treatment. At the same time, treatments that were provided more often conformed to guidelines, and postoperative mortality declined for certain tumor types. This may indicate improved treatment decision-making, although interpretation remains challenging in the absence of additional data on treatment choices, quality of life, and patient preferences. The growing population of older cancer patients places increasing pressure on oncology care and calls for care tailored to their resilience and stage of life. Regional collaboration can support this process. At the same time, more insight is needed into treatment decisions, their impact on quality of life, risk of side effects and toxicity, and the preferences of older patients in order to make well-informed decisions.