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Medical imaging is the main source of artificial radiation exposure. Evidence, however, suggests that patients are poorly informed about radiation exposure when attending diagnostic scans. This review provides an overview of published literature with a focus on nuclear medicine patients on the level of awareness of radiation exposure from diagnostic imaging. A review of available literature on awareness, knowledge and perception of ionising radiation in medical imaging was conducted. Articles that met the inclusion criteria were subjected to critical appraisal using the Mixed Methods Appraisal Tool. 140 articles identified and screened for eligibility, 24 critically assessed and 4 studies included in synthesis. All studies demonstrated that patients were generally lacking awareness about radiation exposure and highlighted a lack of communication between healthcare professionals and patients with respect to radiation exposure. Studies demonstrate a need to better inform patients about their radiation exposure, and further studies focusing on nuclear medicine patients are particularly warranted. Adequate and accurate information is crucial to ensure the principle of informed consent is present. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Radiofrequency ablation (RFA) has shown to improve survival in patients not eligible for surgical resection of colorectal liver metastases. However, recurrences after RFA are a major problem. Adjuvant radioimmunotherapy (RIT) after surgical resection of liver metastases has shown to improve survival. The aim of the present study was to test the hypothesis that adjuvant RIT might be an effective way to prevent recurrent liver metastases after RFA in an experimental model. Methods: Tumours in the liver were induced by intrahepatic injection of 300 000 CC531 cells in male Wag/Rij rats (n = 60). Ten days later, the intrahepatic tumours were treated with RFA. Adjuvant RIT (177Lu-labelled monoclonal antibody MG1 at 300 MBq/kg) was administered intravenously either at the day of RFA (day 10) or 7 days later. Control rats received no treatment. Primary endpoint was survival. Results: Administration of 177Lu-MG1 resulted in a transient decrease in body weight, compared to no adjuvant treatment. However, no other signs of clinical discomfort were registered. Log rank test showed that the survival curves of the groups treated with RIT, either at day 10 or day 17, did not differ significantly from the survival curve of the rats that did not receive adjuvant treatment (P = 0.902). Conclusion: This study shows that adjuvant RIT does not increase survival after RFA of colorectal liver metastases in rats. [Copyright &y& Elsevier]

Abstract: Aims: To report immediate local treatment efficacy and long-term results of cryosurgical ablation (CSA) and radiofrequency ablation (RFA) in patients with colorectal liver metastases not eligible for resection. Methods: Fifty-eight patients with unresectable colorectal liver metastases were included. Under ultrasound guidance, CSA or RFA were performed with or without concomitant resection. CT scanning and FDG-PET were used to determine local efficacy of the ablative procedure. Results: Median follow-up was 26 and 25 months for CSA and RFA, respectively. One and 2-year survival rates were 76 and 61% for CSA and 93 and 75% for RFA, respectively. In a lesion based analysis, the local recurrence rate was 9% after CSA and 6% after RFA. Complication rates were 30 and 11% after CSA and RFA, respectively, (p=0.052). In a subgroup analysis on 43 patients with 104 ablated lesions, CT scan immediate after treatment was not able to predict local treatment failure, whereas FDG-PET scan within 3 weeks after local ablative treatment predicted six of the seven local recurrences. Conclusions: In patients with unresectable colorectal liver metastases, CSA and RFA can be used either alone or as an effective adjunct to resection in achieving complete tumour clearance of the liver. More widespread use of these techniques seems promising but requires further investigation in randomized trials comparing local ablative treatment with chemotherapy. [Copyright &y& Elsevier]

Background: Only human epidermal growth factor receptor (HER)2 status determined by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) has been validated to predict efficacy of HER2-targeting antibody-drug-conjugate trastuzumab emtansine (T-DM1). We propose molecular imaging to explore intra-/interpatient heterogeneity in HER2 mapping of metastatic disease and to identify patients unlikely to benefit from T-DM1. Patients and methods: HER2-positive mBC patients with IHC3+ or FISH ≥2.2 scheduled for T-DM1 underwent a pre-treatment HER2-positron emission tomography (PET)/computed tomography (CT) with 89Zr-trastuzumab. [18F]2-fluoro-2-deoxy-D-glucose (FDG)-PET/CT was performed at baseline and before T-DM1 cycle 2. Patients were grouped into four HER2-PET/CT patterns according to the proportion of FDG-avid tumor load showing relevant 89Zr-trastuzumab uptake (>blood pool activity): patterns A and B were considered positive (>50% or all of the tumor load 'positive'); patterns C and D were considered negative (>50% or all of the tumor load 'negative'). Early FDG-PET/CT was defined as nonresponding when >50% of the tumor load showed no significant reduction of FDG uptake (<15%). Negative (NPV) and positive predictive values (PPV) of HER2-PET/CT, early FDG response and their combination were assessed to predict morphological response (RECIST 1.1) after three T-DM1 cycles and time-to-treatment failure (TTF). Results: In the 56 patients analyzed, 29% had negative HER2-PET/CT while intrapatient heterogeneity (patterns B and C) was found in 46% of patients. Compared with RECIST1.1, respective NPV/PPV for HER2-PET/CT were 88%/72% and 83%/96% for early FDG-PET/CT. Combining HER2-PET/CT and FDG-PET/CT accurately predicted morphological response (PPV and NPV: 100%) and discriminated patients with a median TTF of only 2.8 months [n = 12, 95% confidence interval (CI) 1.4-7.6] from those with a TTF of 15 months (n = 25, 95% CI 9.7-not calculable). Conclusions: Pretreatment imaging of HER2 targeting, combined with early metabolic response assessment holds great promise for improving the understanding of tumor heterogeneity in mBC and for selecting patients who will/will not benefit from T-DM1. [ABSTRACT FROM AUTHOR]

In three patients with catheter-associated candidaemia, use of18F-fluorodeoxyglucose positron emission tomography (FDG-PET) led to the diagnosis ofCandidalung abscesses, which was confirmed by computed tomography and a favourable response to antifungal therapy. It was concluded that FDG-PET is a promising new imaging technique that enables early identification of sites of disseminated candidiasis, and that this technique can be used in the evaluation of therapy. [ABSTRACT FROM AUTHOR]