Combined PET/MR: Where Are We Now? Summary Report of the Second International Workshop on PET/MR Imaging April 8–12, 2013, Tubingen,Germany

This workshop was held a year after the initial positron emission tomography/magnetic resonance (PET/MR) workshop in Tübingen, which was recently reported in this journal. The discussions at the 2013 workshop, however, differed substantially from those of the initial workshop, attesting to the progress of combined PET/MR as an innovative imaging modality. Discussions were focused on the search for truly novel, unique clinical and research applications as well as technical issues such as reliable and accurate approaches for attenuation and scatter correction of PET emission data. The workshop provided hands-on experience with PET and MR imaging. In addition, structured and moderated open discussion sessions, including six dialogue boards and two roundtable discussions, provided input from current and future PET/MR imaging users. This summary provides a snapshot of the current achievements and challenges for PET/MR.     

Dose-Dependent Uptake of 3′-deoxy-3′-[18 F]Fluorothymidine by the Bowel after Total-Body Irradiation

Purpose

The aim of this study is to non-invasively assess early, irradiation-induced normal tissue alterations via metabolic imaging with 3′-deoxy-3′-[¹⁸?F]fluorothymidine ([¹⁸?F]FLT).

Procedures

Twenty-nine male C57BL/6 mice were investigated by [¹⁸?F]FLT positron emission tomography for 7 days after total body irradiation (1, 4, and 8 Gy) versus ‘sham’ irradiation (0 Gy). Target/background ratios were determined. The imaging results were validated by histology and immunohistochemistry (Thymidine kinase 1, Ki-67).

Results

[¹⁸?F]FLT demonstrated a dose-dependent intestinal accumulation post irradiation. Mean target/background ratio (±standard error) 0 Gy: 1.4 (0.2), 1 Gy: 1.7 (0.1), 4 Gy: 3.1 (0.3), 8 Gy: 4.2 (0.6). Receiver operating characteristic analysis (area under the curve, p value): 0 vs. 1 Gy: 0.81, 0.049; 0 vs. 4 Gy: 1.0, 0.0016; and 0 vs. 8 Gy: 1.0, 0.0020. Immunohistochemistry confirmed the results.

Conclusions

[¹⁸?F]FLT seems to provide dose-dependent information on radiation-induced proliferation in the bowel. This opens the perspective for monitoring therapy-related side-effects as well as assessing, e.g., radiation accident victims.     

Buchbesprechungen

Ohne Zusammenfassung     

Hormon-, Eiweiß- und Elektrolythaushalt bei schwersten Verbrennungen

Ohne ZusammenfassungMit 12 Textabbildungen     

Gefahren und Komplikationen bei Eingriffen an der Kardia

Ohne Zusammenfassung Mit 10 Abbildungen     

Weekly docetaxel and carboplatin for recurrent ovarian and peritoneal cancer: a phase II trial

OBJECTIVE: Results of the ICON4/AGO-OVAR-2.2 trial suggest that a platinum/taxane combination provides a survival benefit in relapsed, platinum-sensitive ovarian cancer compared to platinum alone. The optimal specific combination has yet to be determined. The current study evaluates weekly docetaxel and carboplatin in this setting. METHODS: Using a prospective phase II design, patients received weekly docetaxel (35 mg/m2) and carboplatin (AUC=2) administered days 1, 8, and 15 of a 28-day cycle. Initial treatment with a platinum-based regimen was required, with a treatment-free interval of at least 3 months. Patients could have received one prior regimen for recurrence. Biologically evaluable disease (CA-125) could be followed only if measurable disease was not present. Quality of life analysis utilized the FACT-O and FACT/GOG-Ntx scales. RESULTS: Thirty-six patients enrolled in the trial over 29 months. The majority had ovarian cancer (89%) and stage III/IV (97%) disease, with a median initial disease-free interval of 12 months. Most subjects were treated for first recurrence (81%) and had measurable disease (58%). The overall response rate was 67% (PR=52%, CR=15%), with 22% stable disease. Grade 3/4 neutropenia was common (48%) while serious anemia and thrombocytopenia were not. Neuropathy was generally mild and manageable. Carboplatin hypersensitivity led to 11 subjects coming off trial (31%). Diphenhydramine premedication produced a nonsignificant decrease in reaction rate. There was no detectable difference in quality of life due to therapy. CONCLUSION: The weekly regimen of carboplatin and docetaxel has a good response rate with an acceptable toxicity profile.