MRI versus 68Ga-PSMA PET/CT for gross tumour volume delineation in radiation treatment planning of primary prostate cancer.

PURPOSE: Multiparametric magnetic resonance imaging (mpMRI) is widely used in radiation treatment planning of primary prostate cancer (PCA). Focal dose escalation to the dominant intraprostatic lesions (DIPL) may lead to improved PCA control. Prostate-specific membrane antigen (PSMA) is overexpressed in most PCAs. (68)Ga-labelled PSMA inhibitors have demonstrated promising results in detection of PCA with PET/CT. The aim of this study was to compare (68)Ga-PSMA PET/CT with MRI for gross tumour volume (GTV) definition in primary PCA. METHODS: This retrospective study included 22 patients with primary PCA analysed after (68)Ga-PSMA PET/CT and mpMRI. GTVs were delineated on MR images by two radiologists (GTV-MRIrad) and two radiation oncologists separately. Both volumes were merged leading to GTV-MRIint. GTVs based on PET/CT were delineated by two nuclear medicine physicians in consensus (GTV-PET). Laterality (left, right, and left and right prostate lobes) on mpMRI, PET/CT and pathological analysis after biopsy were assessed. RESULTS: Mean GTV-MRIrad, GTV-MRIint and GTV-PET were 5.92, 3.83 and 11.41 cm(3), respectively. GTV-PET was significant larger then GTV-MRIint (p = 0.003). The MRI GTVs GTV-MRIrad and GTV-MRIint showed, respectively, 40 % and 57 % overlap with GTV-PET. GTV-MRIrad and GTV-MRIint included the SUVmax of GTV-PET in 12 and 11 patients (54.6 % and 50 %), respectively. In nine patients (47 %), laterality on mpMRI, PET/CT and histopathology after biopsy was similar. CONCLUSION: Ga-PSMA PET/CT and mpMRI provided concordant results for delineation of the DIPL in 47 % of patients (40 % - 54 % of lesions). GTV-PET was significantly larger than GTV-MRIint. (68)Ga-PSMA PET/CT may have a role in radiation treatment planning for focal radiation to the DIPL. Exact correlation of PET and MRI images with histopathology is needed.

[Dropout behavior during inpatient psychotherapy ]. / Behandlungsabbrüche während einer stationären Psychotherapie.

OBJECTIVES: Dropouts result in far-reaching consequences for the individual patient, fellow patients, therapists, and the clinic. This study was aimed at early identification of patients with a dropout risk. METHODS: Data from patients of the Department of Psychosomatic Medicine and Psychotherapy of the Medical University Clinic of Tübingen (Germany) were analyzed retrospectively in a case-control study (matched). Differences in the results of various questionnaires (SCL-90-R, IIP-D, SF-36) regarding reasons for dropout and sociodemographic data were analyzed. A total of 59 dropouts, 50 females and 9 males, were included. They were split into 28 early dropouts and 31 late dropouts. The data were compared between early and late dropouts and control group. RESULTS: Early dropouts were significantly younger than late dropouts; they tended to live with their parents or on their own, and suffered more frequently from eating disorders. Late dropouts lived together with partners and suffered from somatoform disorders more frequently than early dropouts. The reasons given for dropout did not differ between the groups. No differences between dropouts and the controls were found with respect to psychopathology (SCL- 90-R) and quality of life (SF-36). Late dropouts did show significantly lower scores on the scale "autocracy/dominance" than the controls (IIP). CONCLUSIONS: Therapy dropout is a multifactorial occurrence. It is generally not predictable, though it may be predicted with different instruments on the basis of a diagnosis, especially with respect to interpersonal behavior patterns. In further studies, targeted interventions should be developed and tested which enable procedures to minimize the risk of dropout and to achieve complete treatment according to patients' intentions.