[Compliance to treatment of adolescents with cancer]

Compliance is a very important issue in medicine for three major reasons. Non-compliance has a considerable financial cost for health care systems. Adherence to treatment is the main link between intention to treat and the desired health outcome. Finally, the influence of non-compliance on the conclusions of clinical research trials can have severe consequences. Despite the importance of these issues, our literature review found very few recent studies concerning the compliance of adolescents with cancer. Non-compliance has many causes. The relationship between patient and health care team, the organisational aspects of care and the youth's perception of his/her illness and its treatment all significantly affect adolescents'compliance. The influence of the treatment on young people's lifestyles as well as the physical transformations induced by the treatment are also important factors, due to adolescents desire to conform to their peer group. Family relationships also play a significant part in adolescents'therapeutic adherence. Since the end of the 1990s, research on adherence has focused more on the importance of the doctor-teenager relationship and the strong influence of the patients'perception concerning health in general and his/her illness in particular. Negotiation is an essential component of a successful treatment in teenagers due to their increasing desire for autonomy. Despite numerous recommendations international research has not succeeded in using standardised terms concerning compliance to treatment regimens or come to an agreement on valid assessment methods. Longitudinal studies should be carried out in order to determine causal links between factors and compliance in a methodologically correct manner. Research should be quantitative but must also include the conceptual elements which have been put forward by qualitative research, namely the importance of teenagers'point of view concerning their treatment.