Ce travail de recherche translationnelle a pour objectif de corréler les données de l'imagerie anatomique et fonctionnelle, aux facteurs pronostiques cliniques, biologiques, histologiques, moléculaires du cancer de prostate. Nos travaux ont permis de montrer que l'IRM prostatique permettait de détecter et de stratifier le risque de cancer de prostate dit "significatif", que l'IRM couplée aux biopsies prostatiques ciblées permettait d'identifier plus de cancers de prostate significatifs que les biopsies dites "systématiques", que l'IRM donnait des informations sur l'agressivité du cancer de prostate définie in situ par les marqueurs histologiques et moléculaires, que cette information était plus juste que celle obtenue par la stratégie diagnostique actuelle du dosage de PSA et des biopsies prostatiques qui sous estiment l'agressivité tumorale, qu'il existait cependant des formes de cancer dont l'agressivité ne pouvait être déterminée ni par l'imagerie, ni par l'analyse histologique standard mais seule par une analyse moléculaire. / This study represents a translational research with the objective to identify prognostic biomarkers in prostate cancer (PCa) by means of a radio-genomics strategy that integrates gene expression, biology, histology, and medical images. Our results show that; multiparametric MR imaging of the prostate provide clinically relevant stratification of the risk of showing prostate cancer ; that MRI/TRUS-fusion imaging protocol with limited targeted biopsies detected more men with clinically significant PCa, that we were able to confirm that functional MRI (diffusion) and morphologic MRI (Tmax) were well correlated with tumor aggressiveness as defined by Gleason score and genomic score, that the ADC values of suspicious areas on prostate MR imaging are strongly correlated with post-surgical Gleason score, that ADC values performed significantly better than TRUS biopsy Gleason scores for the prediction of prostate cancer aggressiveness as defined by prostatectomy Gleason score or by Ki-67 proliferation index.

This thesis investigates the acceptability and efficacy of Functional Imagery Training (FIT), a motivational intervention for weight-management. FIT is based on Elaborated Intrusion Theory, delivered in the style of Motivational interviewing (MI), and designed to promote sustained behaviour change and address cravings. It trains the habitual use of affective, goal-directed mental imagery of personal incentives, using imagery to plan behaviours, anticipate obstacles, and mentally try out solutions from previous successes. Participants are taught to update their imagery from their experience, and to generalise their imagery skills to new goals. In study 1, focus groups explored problems and wishes in regards to weight-management, including reactions to Functional Imagery Training (FIT) as a possible intervention. The issue of waning motivation and the desire for motivational app support was expressed in all groups. Participants were positive about FIT. Study 2 was an uncontrolled pilot trial of FIT. Eleven out of 17 participants (65%) lost 5% body weight or more by three months. Participants continued to lose weight during an unsupported 12-month period and experienced mean weight loss of 6kg (SD= 5.7; d=1.06) and mean waistline reduction of 11.5 cm (SD= 7.4; d=1.56) at 15 months. Study 3 compared the impact of FIT with MI on motivation and self-efficacy, over the first month of a randomised controlled trial (RCT) for weight-loss. Structured elicitation and training in goal-related imagery, i.e., FIT, increased motivation and self-efficacy for weight-loss relative to MI. Study 4 was the RCT for weight-loss, comparing FIT and MI over an intervention-supported six-month period, followed by six months unsupported. The FIT group achieved clinically meaningful weight-loss at 6 months (M kg-loss=4.11) and continued weight-loss at 12 months (M kg-loss=6.44); the MI group stabilised by 12 months (M kg-loss=.67), after minimal weight loss at 6 months (M kg-loss=.74). Study 5 qualitatively explored experiences of MI and FIT RCT participants, upon completing the 6-month intervention phase. MI participants wished for continued therapist- support and feared relapse. FIT participants described a mind-set-change and were confident they could maintain changes and overcome challenges using imagery techniques. Given the demonstrated benefit of motivational imagery in weight-control, FIT should be considered and further tested as an intervention for health behaviour change.