The aim of our work was to assess the potential clinical impact of therapeutic education in patients treated with anticancer drugs. One hundred-one ambulatory adult patients (mean age: 60 years, range: 24-88) treated by anticancer chemotherapy were included. The occurrence of adverse events was reported by 83% of the patients. Twenty-one percent (14/67) of the patients were not compliant with their supportive care treatment, 60% (60/101) took over-the-counter medications (one contraindication identified) and 14% (14/101) claimed they had received no counsel on risk behaviour (UV exposure, lack of contraception, driving) from health care professionals. Overall, 11% (44/397) of adverse events were associated with a lack of information. Twelve percent (4/33) of the calls to the doctor, 6% (1/17) of the visits to the physician and 21% (3/14) of the hospitalizations could be associated with a lack of therapeutic education. These data enlighten the importance of therapeutic education of cancer patients treated by chemotherapy.