Chatbots (contraction of "chat" and "robot") are a computer software program that use statistical learning and aim to simulate a conversation by text or voice message. The use of these chatbots was evaluated as part of the increase in therapeutic adherence and information on well-being and mental health.

In clinical studies, chatbots are useful in gathering information through questionnaires directly submitted during conversations or through keyword analyzes. There is no longer any delay between the moment the patient notices a side effect, for example, and the moment when the patient announces it during a consultation. The responses given by the chatbot do not constitute medical advice and only provide information on the treatments envisaged or in progress in the context of the management of breast cancer.

The main objective of the study is to show that the chatbot Vik's answers to the common questions asked by breast cancer patients about their therapeutic management are at least as satisfactory as answers given by a committee of multidisciplinary doctors

A total of 20 most frequently asked questions will be defined on a cohort of 150 breast cancer patients. These questions will be asked on the one hand to the chatbot Vik and on the other hand to a multidisciplinary medical committee (surgeon oncologist, medical oncologist and oncologist radiotherapist). The scientific quality of the responses of the two groups will be validated by a second multidisciplinary group of physicians, independent of the first.

A cohort of 150 patients will then be randomized blind and in 1 to 1 to receive the responses of the chatbot Vik and the answers of the doctors' committee. Each patient will then have to answer the EORTC QLQ-INFO255-7 questionnaire, evaluating the quality of the medical information.

Inclusion Criteria:

• over 18 years
• paitents with breast cancer

Exclusion Criteria:

• Patient unable to formulate his opposition
• Patient with cancer other than breast cancer

Women with breast cancer or in remission