Acute myeloid leukaemia (AML) is a rapidly progressing blood cancer. Without treatment, AML is fatal. With treatment, some patients can be completely cured, however others will face treatment failure and relapse. Finding the best available treatment for each patient is essential for improving the survival rate of this disease. The Snjider lab at ETH has pioneered a new technique called pharmacoscopy, where cancer cells taken from each patient are screened across a panel of nearly 100 drugs to find which are the most effective. A recent pharmacoscopy study in 34 AML patients in Switzerland has revealed that different patients can have very different drug response profiles, despite having a similar clinical diagnosis.