Résumé : Cancer is a central problem in our modern society and its prevalence is constantly increasing. However, medical progresses are leading to a higher survival rate. This disease is known as a stress factor which could lead to significant psychological distress and to several disorders. DSM-5 includes nosographic changes which cause consequences in the oncology diagnostic process. In this article, the diagnostic criteria for adjustment disorder, depression and posttraumatic stress disorder will be discussed. We will question the relevance of the adjustment disorder in the field of oncology and will rather propose to create "cancer-specific stress syndrome", and to reflect the possibility of a subsyndromal (or subthreshold) diagnosis.We will also insist on the need of taking into account the post-traumatic dimensions in our practice, despite the severe restrictions imposed by the DSM-5. An accurate diagnosis will allow the mental health professionals to choose the most effective therapeutic means.