Background Cancer centers are pressured to deliver high-quality services that can be measured and improved, which has led to an increase of assessments in many countries. A critical area of quality improvement is to improve patient outcome. An overview of existing assessments can help stakeholders (e.g., healthcare professionals, managers and policy makers) improve the quality of cancer research and care and lead to patient benefits. This paper presents key aspects of assessments undertaken by European cancer centers, such as: are assessments mandatory or voluntary? Do they focus on evaluating research, care or both? And are they international or national? Methods A survey was sent to 33 cancer centers in 28 European Union member states. Participants were asked to score the specifics for each assessment that they listed. Results Based on the responses from 19 cancer centers from 18 member states, we found 109 assessments. The numbers have steadily increased from 1990’s till 2015. Although, a majority of assessments are on patient-care aspects (n = 45), it is unclear how many of those include assessing patient benefits. Only few assessments cover basic research. There is an increasing trend towards mixed assessments (i.e., combining research and patient-care aspects) Conclusions The need for assessments in cancer centers is increasing. To improve efforts in the quality of research and patient care and to prevent new assessments that “reinvent the wheel”, it is advised to start comparative research into the assessments that are likely to bring patient benefits and improve patient outcome. Do assessments provide consistent and reliable information that create added value for all key stakeholders?