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Multiparametric magnetic resonance imaging (mpMRI) and targeted biopsy (TB) facilitate accurate detection of clinically significant prostate cancer (csPC). However, it remains unclear how targeted cores should be applied for accurate diagnosis of csPC.To assess csPC detection rates for two target-directed MRI/transrectal ultrasonography (TRUS) fusion biopsy approaches, conventional TB and target saturation biopsy (TS).This was a prospective single-center study of outcomes for transperineal MRI/TRUS fusion biopsies for 170 men. Half of the men (n = 85) were randomized to conventional TB with four cores per lesion and half (n = 85) to TS with nine cores. Biopsies were performed by three experienced board-certified urologists.PC and csPC (International Society of Urological Pathology grade group ≥2) detection rates for systematic biopsy (SB), TB, and TS were analyzed using McNemar's test for intrapatient comparisons and Fisher's exact test for TS versus TB. A combination of targeted biopsy (TS or TB) and SB served as the reference.According to the reference, csPC was diagnosed for 57 men in the TS group and 36 men in the TB group. Of these, TS detected 57/57 csPC cases and TB detected 33/36 csPC cases (p = 0.058). Detection of Gleason grade group 1 disease was 10/12 cases with TS and 8/17 cases with TB (p = 0.055). In addition, TS detected 97% of 63 csPC lesions, compared to 86% with TB (p = 0.1). Limitations include the single-center design, the limited generalizability owing to the transperineal biopsy route, the lack of central review of pathology and radical prostatectomy correlation, and uneven distributions of csPC prevalence, Prostate Imaging-Reporting and Data System (PI-RADS) 5 lesions, men with two or more PI-RADS ≥3 lesions, and prostate-specific antigen density between the groups, which may have affected the results.In our study, rates of csPC detection did not significantly differ between TS and TB.In this study, we investigated two targeted approaches for taking prostate biopsy samples after observation of suspicious lesions on prostate scans. We found that the rates of detection of prostate cancer did not significantly differ between the two approaches.

BACKGROUND: Computed tomography (CT) studies are requested by specialists from most medical disciplines and play a vital role in the diagnosis and treatment of patients. It follows that physicians of all specialties should possess basic knowledge of computed tomography, its proper use, and the radiation exposure associated with it. METHODS: This review is based on publications retrieved by a selective search of the literature. RESULTS: Approximately 12 million CT studies are carried out in Germany each year, and the trend is rising. Approximately 9% of all diagnostic studies involving ionizing radiation are CT studies. On average, more than 60% of the collective effective dose due to medical radiation exposure is attributable to CT. There are two types of radiation effects caused by ionizing radiation: stochastic and deterministic. The additional, individual relative lifetime cancer mortality risk due to ionizing radiation with whole-body exposure at a low single dose is estimated at 5% per sievert. Radiation exposure from CT studies of the head and trunk, e.g. of a patient with polytrauma, corresponds to an additional lifetime cancer mortality risk of approximately 0.1% at an effective dose of approximately 20 millisievert. CONCLUSION: The radiation exposure due to CT, and the risks to which patients are subjected by it, have become more important with greater use of CT. Technical advances, targeted dose monitoring, and analyses of dose data can help identify areas where improvement is necessary, in furtherance of the overriding goal of lowering patients’ radiation exposure while preserving adequate image quality.

Cutaneous squamous cell carcinoma (cSCC) numbers among the most common types of skin cancer and is known as one of the cancer entities with the highest mutational burden among all solid tumours. Due to the positive correlation between mutational burden and response rate to inhibitors of the programmed cell death 1 (PD-1), those inhibitors are considered promising candidates for the systemic therapy of cSCC. Recently, the PD-1 inhibitors pembrolizumab, nivolumab and cemiplimab demonstrated efficacy in the systemic treatment of locally advanced or metastatic cSCC leading to the approval of cemiplimab by the FDA (U.S. Food and Drug Administration) in 2018 and the EMA (European Medicines Agency) in 2019. Patients with haematological malignancies tend to develop skin cancers of high aggressiveness, enhanced cumulative recurrence rate and higher rates of metastases with subsequent death. Chronic lymphocytic leukaemia (CLL) is the most frequent type of leukaemia in the United States and Europe with the majority of patients older than 50 years of age. This neoplasm predominantly originates from B -cells leading to an impaired immune system of the patient. Although CLL is a B-cell malignancy, studies have also described the involvement of T cells in the pathogenesis and progression of the disease with contradictory findings on the effects of PD-1 inhibitors in CLL. Due to their underlying hematologic malignancy, these patients have commonly no access to PD-1 inhibitor trials for treatment of advanced cSCC. We report on two patients with locally advanced or metastatic cSCC. Both patients had been suffering from a CLL for many years without indication for treatment. Despite a potential immunosuppressive state of the patients due to their CLL, both were treated with the PD-1 inhibitor pembrolizumab resulting in different therapy outcomes.

Background Radiological imaging such as computed tomography (CT) is used frequently for disease staging and therapy monitoring in advanced skin cancer patients. Detected lesions of unclear dignity are a common challenge for treating physicians. The aim of this study was to assess the frequency and outcome of CT-guided biopsy (CTGB) of radiologically unclear, suspicious lesions and to depict its usefulness in different clinical settings. Methods This retrospective monocentric study included advanced skin cancer patients (melanoma, Merkel cell carcinoma, squamous cell carcinoma, angiosarcoma, cutaneous lymphoma) with radiologically unclear lesions who underwent CTGB between 2010 and 2018. Results Of 59 skin cancer patients who received CTGB, 47 received CTGB to clarify radiologically suspicious lesions of unclear dignity. 32 patients had no systemic therapy (cohort A), while 15 patients received systemic treatment at CTGB (cohort B). In both cohorts, CTGB revealed skin cancer metastasis in a large proportion of patients (37.5%, 40.0%, respectively), but benign tissue showing inflammation, fibrosis or infection in an equally large percentage (37.5%, 46.7%, respectively). Additionally, a significant number of other cancer entities was found (25.0%, 13.3%, respectively). In patients receiving BRAF/MEK inhibitors, CTGB confirmed suspicious lesions as skin cancer metastasis in 83.3%, leading to treatment change. In immune checkpoint inhibitor-treated patients, skin cancer metastasis was confirmed in 11.1% of patients only, whereas benign tissue changes (inflammation/fibrosis) were found in 77.8%. Conclusions Our results highlight the relevance of clarifying radiologically unclear lesions by CTGB before start or change of an anti-tumour therapy to exclude benign alterations and secondary malignancies.

The aim of this phantom study is to examine radiation doses of dual- and single-energy computed tomography (DECT and SECT) in the chest and upper abdomen for three different multi-slice CT scanners. A total of 34 CT protocols were examined with the phantom N1 LUNGMAN. Four different CT examination types of different anatomic regions were performed both in single- and dual-energy technique: chest, aorta, pulmonary arteries for suspected pulmonary embolism and liver. Radiation doses were examined for the CT dose index CTDIvol and dose-length product (DLP). Radiation doses of DECT were significantly higher than doses for SECT. In terms of CTDIvol, radiation doses were 1.1–3.2 times higher, and in terms of DLP, these were 1.1–3.8 times higher for DECT compared with SECT. The third-generation dual-source CT applied the lowest dose in 7 of 15 different examination types of different anatomic regions.

Purpose/introduction [18F]FDG-PET/CT is the standard imaging-technique for radiation treatment (RT) planning in locally advanced non-small cell lung cancer (NSCLC). The purpose of this study was to examine the additional value of endobronchial-ultrasound transbronchial needle aspiration (EBUS-TBNA) to standard PET/CT for mediastinal lymph-node (LN) staging and its impact on clinical target volume (CTV). Materials and methods All consecutive patients with primary stage III NSCLC who underwent [18F]FDG-PET/CT and EBUS-TBNA prior to RT were analyzed from 12/2011 to 06/2018. LN-stations were assessed by an expert-radiologist and a nuclear medicine-physician. CTV was evaluated by two independent radiation oncologists. LNs were grouped with increasing distance along the lymphatic chains from primary tumor into echelon-1 (ipsilateral hilum), echelon-2 (LN-station 7 and ipsilateral 4), and echelon-3 (remaining mediastinum and contralateral hilum). Results A total of 675 LN-stations of which 291 were positive for tumor-cells, were sampled by EBUS-TBNA in 180 patients. The rate of EBUS-positive LNs was 43% among all sampled LNs. EBUS-positivity in EBUS-probed LNs decreased from 85.8% in echelon-1 LNs to 42.4%/ 9.6% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher’s exact test). The false discovery rate of PET in comparison with EBUS results rose from 5.3% in echelon-1 to 32.9%/ 69.1% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher’s exact test). Sensitivity and specificity of FDG-PET/CT ranged from 85 to 99% and 67 to 80% for the different echelons. In 22.2% patients, EBUS-TBNA finding triggered changes of the treated CTV, compared with contouring algorithms based on FDG-avidity as the sole criterion for inclusion. CTV was enlarged in 6.7% patients due to EBUS-positivity in PET-negative LN-station and reduced in 15.5% by exclusion of an EBUS-negative but PET-positive LN-station. Conclusion The false discovery rate of [18F]FDG-PET/CT increased markedly with distance from the primary tumor. Inclusion of systematic mediastinal LN mapping by EBUS-TBNA in addition to PET/CT has the potential to increase accuracy of target volume definition, particularly in echelon-3 LNs. EBUS-TBNA is recommended as integral part of staging for radiochemotherapy in stage III NSCLC.

Purpose To assess suspected acute stroke, the computed tomography (CT) protocol contains a non-contrast CT (NCCT), a CT angiography (CTA), and a CT perfusion (CTP). Due to assumably high radiation doses of the complete protocol, the aim of this study is to examine radiation exposure and to establish diagnostic reference levels (DRLs). Methods In this retrospective study, dose data of 921 patients with initial CT imaging for suspected acute stroke and dose monitoring with a DICOM header–based tracking and monitoring software were analyzed. Between June 2017 and January 2020, 1655 CT scans were included, which were performed on three different modern multi-slice CT scanners, including 921 NCCT, 465 CTA, and 269 CTP scans. Radiation exposure was reported for CT dose index (CTDIvol) and dose-length product (DLP). DRLs were set at the 75th percentile of dose distribution. Results DRLs were assessed for each step (CTDIvol/DLP): NCCT 33.9 mGy/527.8 mGy cm and CTA 13.7 mGy/478.3 mGy cm. Radiation exposure of CTP was invariable and depended on CT device and its protocol settings with CTDIvol 124.9–258.2 mGy and DLP 1852.6–3044.3 mGy cm. Conclusion Performing complementary CT techniques such as CTA and CTP for the assessment of acute stroke increases total radiation exposure. Hence, the revised DRLs for the complete protocol are required, where our local DRLs may help as benchmarks.

Purpose This study aims to determine local diagnostic reference levels (LDRLs) of intra-arterial chemotherapy (IAC) procedures of pediatric patients with retinoblastoma (RB) to provide data for establishing diagnostic reference levels (DRLs) in pediatric interventional radiology (IR). Methods In a retrospective study design, LDRLs and achievable dose (AD) were assessed for children undergoing superselective IAC for RB treatment. All procedures were performed at the flat-panel angiography systems (I) ArtisQ biplane (Siemens Healthineers) and (II) Allura Xper (Philips Healthcare). Patients were differentiated according to age (A1: 1–3 months; A2: 4–12 months; A3: 13–72 months; A4: 73 months–10 years; A5: > 10 years), sex, conducted or not-conducted chemotherapy. Results 248 neurointerventional procedures of 130 pediatric patients (median age 14.5 months, range 5–127 months) with RB (68 unilateral, 62 bilateral) could be included between January 2010 and March 2020. The following diagnostic reference values, AD, and mean values could be determined: (A2) DRL 3.9 Gy cm2, AD 2.9 Gy cm2, mean 3.5 Gy cm2; (A3) DRL 7.0 Gy cm2, AD 4.3 Gy cm2, mean 6.0 Gy cm2; (A4) DRL 14.5 Gy cm2, AD 10.7 Gy cm2, mean 10.8 Gy cm2; (A5) AD 8.8 Gy cm2, mean 8.8 Gy cm2. Kruskal-Wallis-test confirmed a significant dose difference between the examined age groups (A2–A5) (p p = 0.076) and conducted or not-conducted chemotherapy (p = 0.627). A successful procedure was achieved in 207/248 cases. Conclusion We report on radiation exposure during superselective IAC of a pediatric cohort at the German Retinoblastoma Referral Centre. Although an IAC formally represents a therapeutic procedure, our results confirm that radiation exposure lies within the exposure of a diagnostic interventional procedure. DRLs for superselective IAC are substantially lower compared with DRLs of more complex endovascular interventions.

To study the value of 2-deoxy-2-[18F]fluoro-D-glucose([18F]FDG) positron emission tomography/computed tomography (PET/CT) and [18F]FDG positron emission tomography/magnetic resonance imaging (PET/MRI) in assessing immunocompromised patients with suspected malignancy or infection. [18F]FDG-PET/CT and [18F]FDG-PET/MRI examinations of patients who were immunocompromised after receiving lung, heart, pancreas, kidney, liver, or combined kidney-liver transplants were analyzed in this retrospective study. Patients underwent whole-body hybrid-imaging because of clinical signs of malignancy and/or infection. Findings were assessed by molecular features ([18F]FDG-uptake) and morphological changes. The final diagnosis, which was arrived at after review of clinical, laboratory, and histopathologic analyses and follow-up imaging studies, served as the reference standard. Altogether, (i) 28 contrast-enhanced [18F]FDG-PET/CT scans (CE-PET/CT), (ii) 33 non-contrast [18F]FDG-PET/CT scans (NC-PET/CT), and (iii) 18 [18F]FDG-PET/MRI scans were included. Additionally, 12/62 patients underwent follow-up PET imaging to rule out vital tumor or metabolic active inflammatory processes. CE-PET/CT exhibited 94.4% sensitivity, 80.0% specificity, 89.5% positive predictive value (PPV), 88.9% negative predictive value (NPV), and 89.3% accuracy with regard to the reference standard. NC-PET/CT exhibited 91.3% sensitivity, 80.0% specificity, 91.3% PPV, 80.0% NPV, and 87.9% accuracy. PET/MRI exhibited 88.6% sensitivity, 99.2% specificity, 99.6% PPV, 81.3% NPV, and 94.4% accuracy. Exact McNemar statistical test (one-sided) showed significant difference between the CT-/MR-component alone and the integrated PET/CT and PET/MRI for diagnosis of malignancy or infection (p value

To analyze tumor response, survival and safety in patients with non-resectable hepatocellular carcinoma (HCC) treated with transarterial hepatic chemoembolization using degradable starch microspheres (DSM-TACE) combined with doxorubicin who had no local interventional or systemic therapy alternative according to an interdisciplinary conference. In this retrospective study, 28 patients (23 male, 5 female, median age 67 years) with unresectable HCC, serum bilirubin levels 3 mg/dl and contraindications to Sorafenib, RFA, SIRT or cTACE were included. DSM-TACE was performed using Embocept DSM-TACE could be technically successfully performed in all 28 patients. At control imaging after three treatments, the overall rates of complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) were 14.3 %, 25 %, 39.3 % and 21.4 %, respectively, according to mRECIST. With regard to BCLC stages, the results were as follows (CR, PR, PD): BCLC A (n = 8): 7.1 %, 7.1 %, 10.7 %, 1.2 %; BCLC B (n = 12): 0 %, 10.7 %, 17.9 %, 14.3 %; BCLC C (n = 5): 0 %, 3.6 %, 10.7 %, 3.6 %; BCLC D (n = 3): 3.6 %, 3.6 %, 0 %, 3.6 %. According to this, DSM-TACE showed an overall good median survival of 682 days, although the patients' survival was strictly dependent on BCLC stage. DSM-TACE is a safe and promising treatment alternative for patients with unresectable HCC who are ineligible for other loco-regional therapies. · DSM-TACE is a safe treatment alternative for patients ineligible for other local or systemic treatments.. · DSM-TACE did not influence the MELD-score in our study population.. · Patients treated with DSM-TACE showed an overall good median survival of 682 days, strictly dependent on BCLC stage..· Haubold J, Reinboldt MP, Wetter A et al. DSM-TACE of HCC: Evaluation of Tumor Response in Patients Ineligible for Other Systemic or Loco-Regional Therapies. Fortschr Röntgenstr 2020; 192: 862 - 869. Die Studie wurde durchgeführt, um das Tumoransprechen, das Überleben und die Sicherheit der Behandlung durch transarterielle Chemoembolisation mit abbaubaren Stärke-Mikropartikeln in Kombination mit Doxorubicin (DSM-TACE) bei Patienten mit inoperablem hepatozellulärem Karzinom (HCC) zu analysieren. Die Patienten hatten dabei gemäß einer interdisziplinären Konferenz keine lokale oder systemische Therapiealternative. In diese retrospektive Studie wurden 28 Patienten (23 männlich, 5 weiblich, mittleres Alter 67 Jahre) mit inoperablem HCC, Serum-Bilirubinspiegel 3 mg/dl und Kontraindikationen gegen andere lokale oder systemische Therapien eingeschlossen. DSM-TACE wurde 3-mal alle 4–6 Wochen mit Embocept DSM-TACE konnte bei allen 28 Patienten technisch erfolgreich durchgeführt werden. Bei der Kontrollbildgebung nach 3 Therapien lagen die Gesamtraten für das vollständige Ansprechen (CR), das partielle Ansprechen (PR), die stabile Erkrankung (SD) und die progressive Erkrankung (PD) laut mRECIST bei 14,3 %, 25 %, 39,3 % bzw. 21,4 %. In Bezug auf die BCLC-Stufen ergaben sich folgende Ergebnisse (CR, PR, PD): BCLC A (n = 8): 7,1 %, 7,1 %, 10,7 %, 1,2 %; BCLC B (n = 12): 0 %, 10,7 %, 17,9 %, 14,3 %; BCLC C (n = 5): 0 %, 3,6 %, 10,7 %, 3,6 %; BCLC D (n = 3): 3,6 %, 3,6 %, 0 %, 3,6 %. Dementsprechend zeigte die DSM-TACE ein insgesamt gutes medianes Überleben von 682 Tagen, wobei das Überleben der Patienten streng vom BCLC-Stadium abhängig war. DSM-TACE ist eine sichere und vielversprechende Behandlungsalternative für Patienten mit einem inoperablen HCC, die für andere lokale und systemische Therapien nicht geeignet sind. · DSM-TACE ist eine sichere Behandlungsalternative für Patienten mit einem HCC, die für andere lokale und systemische Therapien nicht geeignet sind.. · DSM-TACE hatte in unserer Studienpopulation keinen Einfluss auf den MELD-Score.. · Die mit DSM-TACE behandelten Patienten zeigten ein insgesamt gutes medianes Überleben von 682 Tagen, das strikt vom BCLC-Stadium abhängig war..

Purpose The aim of this study was to determine local diagnostic reference levels (DRLs) during endovascular diagnostics and therapy of carotid-cavernous fistulas (CCF). Methods In a retrospective study design, DRLs, achievable dose (AD) and mean values were assessed for all patients with CCF undergoing diagnostic angiography (I) or embolization (II). All procedures were performed with the flat-panel angiography system Allura Xper (Philips Healthcare). Interventional procedures were differentiated according to the type of CCF and the type of procedure. Results In total, 86 neurointerventional procedures of 48 patients with CCF were executed between February 2010 and July 2021. The following DRLs, AD and mean values could be determined: (I) DRL 215 Gy ∙ cm2, AD 169 Gy ∙ cm2, mean 165 Gy ∙ cm2; (II) DRL 350 Gy ∙ cm2, AD 226 Gy ∙ cm2, mean 266 Gy ∙ cm2. Dose levels of embolization were significantly higher compared to diagnostic angiography (p Conclusion This article reports on diagnostic and therapeutic DRLs in the management of CCF that could serve as a benchmark for the national radiation protection authorities. Differentiation by fistula type or embolization method does not seem to be useful.

The pivotal PACIFIC trial defined durvalumab consolidation as the new standard of care in patients with stage III non-small-cell lung cancer treated with definitive radiochemotherapy. The authors characterized the durvalumab effect after induction chemotherapy according to the ESPATUE trial and definitive radiochemotherapy. All consecutive patients with stage III non-small-cell lung cancer receiving definitive radiochemotherapy between January 2017 and February 2020 were included. Primary end points were progression-free survival and overall survival. Altogether, 160 patients (75 PD-L1-positive, 62 PD-L1-negative, 23 unknown) received definitive radiochemotherapy, 146 (91%) of whom received prior induction chemotherapy. Durvalumab consolidation showed high effectiveness overall and in the good-risk group according to the PACIFIC trial (log-rank test: p < 0.005). Hazard ratios for progression-free survival and overall survival were at the lower limits of those in the PACIFIC trial. These results were robust to adjustment for potential confounders by propensity score weighting. Eastern Cooperative Oncology Group (ECOG) performance status was the most important pretreatment prognostic factor. Tweetable abstract High effectiveness according to the PACIFIC and ESPATUE trials: patients were treated with induction chemotherapy, definitive radiochemotherapy and consolidation immunotherapy. A durable and remarkable tumor response was achieved in the real-world clinical routine. Plain language summary The PACIFIC trial is the major landmark trial for stage III non-small-cell lung cancer (NSCLC) patients treated with combined chemoradiation and defined immunotherapy as maintenance treatment and the new standard of care in patients with stage III NSCLC. Here the authors report a retrospective study comparing consecutive stage III NSCLC patients receiving induction chemotherapy and definitive chemoradiation with or without durvalumab consolidation in a high-volume lung cancer center. After induction chemotherapy, chemoradiation and immune checkpoint inhibition, a durable and remarkable tumor response can be achieved in the clinical routine. Consolidation immunotherapy with durvalumab can be confirmed as a strong innovative therapeutic option in NSCLC in almost all subgroups of patients.

Background Radiation exposures from computed tomography (CT) in children are inadequately studied. Diagnostic reference levels (DRLs) can help optimise radiation doses. Objective To determine local DRLs for paediatric chest CT performed mainly on modern dual-source, multi-slice CT scanners as a function of patient size. Materials and methods Five hundred thirty-eight chest CT scans in 345 children under 15 years (y) of age (median age: 8 y, interquartile range [IQR]: 4–13 y) performed on four different CT scanners (38% on third-generation and 43% on second-generation dual-source CT) between November 2013 and December 2020 were retrospectively analysed. Examinations were grouped by water-equivalent diameter as a measure of patient size. DRLs for volume CT dose index (CTDIvol) and dose-length product (DLP) were determined for six different patient sizes and compared to national and European DRLs. Results The DRLs for CTDIvol and DLP are determined for each patient size group as a function of water-equivalent diameter as follows: (I) n = 22; median: age 7 months): 0.4 mGy, 7 mGy·cm; (II) 13 cm to less than 17 cm (n = 151; median: age 3 y): 1.2 mGy, 25 mGy·cm; (III) 17 cm to less than 21 cm (n = 211; median: age 8 y): 1.7 mGy, 44 mGy·cm; (IV) 21 cm to less than 25 cm (n = 97; median: age 14 y): 3.0 mGy, 88 mGy·cm; (V) 25 cm to less than 29 cm (n = 42; median: age 14 y): 4.5 mGy, 135 mGy·cm; (VI) ≥ 29 cm (n = 15; median: age 14 y): 8.0 mGy, 241 mGy·cm. Compared with corresponding age and weight groups, our size-based DRLs for DLP are 54% to 71% lower than national and 23% to 85% lower than European DRLs. Conclusion We developed DRLs for paediatric chest CT as a function of patient size with substantially lower values than national and European DRLs. Precise knowledge of size-based DRLs may assist other institutions in further dose optimisation in children.

Background In the assessment of diseases causing skeletal lesions such as multiple myeloma (MM), whole-body low-dose computed tomography (WBLDCT) is a sensitive diagnostic imaging modality, which has the potential to replace the conventional radiographic survey. Purpose To optimize radiation protection and examine radiation exposure, and effective and organ doses of WBLDCT using different modern dual-source CT (DSCT) devices, and to establish local diagnostic reference levels (DRL). Material and Methods In this retrospective study, 281 WBLDCT scans of 232 patients performed between January 2017 and April 2020 either on a second- (A) or third-generation (B) DSCT device could be included. Radiation exposure indices and organ and effective doses were calculated using a commercially available automated dose-tracking software based on Monte-Carlo simulation techniques. Results The radiation exposure indices and effective doses were distributed as follows (median, interquartile range): (A) second-generation DSCT: volume-weighted CT dose index (CTDIvol) 1.78 mGy (1.47–2.17 mGy); dose length product (DLP) 282.8 mGy·cm (224.6–319.4 mGy·cm), effective dose (ED) 1.87 mSv (1.61–2.17 mSv) and (B) third-generation DSCT: CTDIvol 0.56 mGy (0.47–0.67 mGy), DLP 92.0 mGy·cm (73.7–107.6 mGy·cm), ED 0.61 mSv (0.52–0.69 mSv). Radiation exposure indices and effective and organ doses were significantly lower with third-generation DSCT ( P vol at 0.75 mGy and DLP at 120 mGy·cm. Conclusion Third-generation DSCT requires significantly lower radiation dose for WBLDCT than second-generation DSCT and has an effective dose below reported doses for radiographic skeletal surveys. To ensure radiation protection, DRLs regarding WBLDCT are required, where our locally determined values may help as benchmarks.

Objectives To validate, in an external cohort, three novel risk models, including the recently updated European Randomized Study of Screening for Prostate Cancer (ERSPC) risk calculator, that combine multiparametric magnetic resonance imaging (mpMRI) and clinical variables to predict clinically significant prostate cancer (PCa). Patients and methods We retrospectively analysed 307 men who underwent mpMRI prior to transperineal ultrasound fusion biopsy between October 2015 and July 2018 at two German centres. mpMRI was rated by Prostate Imaging Reporting and Data System (PI-RADS) v2.0 and clinically significant PCa was defined as International Society of Urological Pathology Gleason grade group ≥2. The prediction performance of the three models (MRI-ERSPC-3/4, and two risk models published by Radtke et al. and Distler et al., ModRad and ModDis) were compared using receiver-operating characteristic (ROC) curve analyses, with area under the ROC curve (AUC), calibration curve analyses and decision curves used to assess net benefit. Results The AUCs of the three novel models (MRI-ERSPC-3/4, ModRad and ModDis) were 0.82, 0.85 and 0.83, respectively. Calibration curve analyses showed the best intercept for MRI-ERSPC-3 and -4 of 0.35 and 0.76. Net benefit analyses indicated clear benefit of the MRI-ERSPC-3/4 risk models compared with the other two validated models. The MRI-ERSPC-3/4 risk models demonstrated a discrimination benefit for a risk threshold of up to 15% for clinically significant PCa as compared to the other risk models. Conclusion In our external validation of three novel prostate cancer risk models, which incorporate mpMRI findings, a head-to-head comparison indicated that the MRI-ERSPC-3/4 risk model in particular could help to reduce unnecessary biopsies.

The selective intra-arterial nimodipine application for the treatment of cerebral vasospasm (CVS) in patients after spontaneous subarachnoid hemorrhage (sSAH) is widely employed. The purpose of this study is to examine the radiation exposure and to determine local diagnostic reference levels (DRLs) of intra-arterial nimodipine therapy. In a retrospective study design, DRLs and achievable dose (AD) were assessed for all patients undergoing (I) selective intra-arterial nimodipine application or (II) additional mechanical angioplasty for CVS treatment. Interventional procedures were differentiated according to the type of procedure and the number of probed vessels. Altogether 494 neurointerventional procedures of 121 patients with CVS due to sSAH could be included. The radiation exposure indices were distributed as follows: (I) DRL 74.3 Gy·cm2, AD 59.8 Gy·cm2; (II) DRL 128.3 Gy·cm2, AD 94.5 Gy·cm2. Kruskal–Wallis test confirmed significant dose difference considering the number of probed vessels (p< 0.001). The mean cumulative dose per patient was 254.9 Gy·cm2 (interquartile range 88.6–315.6 Gy·cm2). The DRLs of intra-arterial nimodipine therapy are substantially lower compared with DRLs proposed for other therapeutic interventions, such as thrombectomy or aneurysm coiling. However, repeated therapy sessions are often required, bearing the potential risk of a cumulatively higher radiation exposure.

The purpose of this study is to examine radiation doses and image quality of a low-dose (LD) protocol for chest and abdomen/pelvis (CAP) CT compared with a standard (STD) protocol. A total of 361 patients were included between October 2019 and April 2020; 104 patients with LD-protocol (100 kV, ref mAs 80 (chest)/145 (abdomen/pelvis)) and 257 patients with STD-protocol (100 kV, ref mAs 100 (chest)/180 (abdomen/pelvis)) at second-generation dual-source CT. Radiation doses for CTDIvol and DLP, and objective and subjective image qualities of 50 examinations from each group were evaluated. The LD-protocol applied significantly lower radiation doses compared with the STD-protocol (p

Purpose This study aims to determine local diagnostic reference levels (DRLs) in the endovascular therapy (EVT) of patients with cranial and spinal dural arteriovenous fistula (dAVF). Methods In a retrospective study design, DRLs and achievable dose (AD) were assessed for all patients with cranial and spinal dAVF undergoing EVT (I) or diagnostic angiography (II). All procedures were performed at the flat-panel angiography-system Allura Xper (Philips Healthcare). Interventional procedures were differentiated according to the region of fistula and the type of procedure. Results In total, 264 neurointerventional procedures of 131 patients with dAVF (94 cranial, 37 spinal) were executed between 02/2010 and 12/2020. The following DRLs, AD, and mean values could be determined: for cranial dAVF (I) DRL 507.33 Gy cm2, AD 369.79 Gy cm2, mean 396.51 Gy cm2; (II) DRL 256.65 Gy cm2, AD 214.19 Gy cm2, mean 211.80 Gy cm2; for spinal dAVF (I) DRL 482.72 Gy cm2, AD 275.98 Gy cm2, mean 347.12 Gy cm2; (II) DRL 396.39 Gy cm2, AD 210.57 Gy cm2, mean 299.55 Gy cm2. Dose levels of EVT were significantly higher compared to diagnostic angiographies (p Conclusion Our results could be used for establishing DRLs in the EVT of cranial and spinal dAVF. Because radiation exposure to comparably complex interventions such as AVM embolization is similar, it may be useful to determine general DRLs for both entities together.

A limitation of using 68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA) for detection and staging of prostate cancer is a frequently observed halo artifact around the urinary bladder caused by inaccurate scatter correction (SC) of PET data. The aim of this study was to investigate the impact of unrenormalized absolute SC on 68Ga-PSMA PET quantification in PET/MRI of the prostate in 100 patients. Methods: The PET data of 100 patients were reconstructed twice using standard SC and improved unrenormalized SC. The visual presence of the halo artifact was rated in each PET data reconstruction using 5 grades (0, no halo artifact; 4, severe halo artifact). The number of visible lesions in the pelvis was recorded. SUVmean and SUVmax were measured in the lesions, in the bladder, in the gluteus maximus, and within the halo margin. Furthermore, the signal-to-noise-ratio and image noise were measured in all PET data. Relative differences between standard and unrenormalized SC were calculated. Results: With standard SC, the average grade in the presence of the halo artifact was 2 (moderate halo artifact), whereas for unrenormalized SC, the average grade was 0.9 (slight halo artifact). The same number of congruent lesions (n = 74) was detected for both PET data reconstructions. Relative changes in PET signal-to-noise-ratio and image noise were not statistically significant (P > 0.05). The mean (±SD) increase in SUVmean using unrenormalized SC was 23.0% ± 9.2% in the gluteus maximus, 7.1% ± 4.5% in the bladder, 325.4% ± 748.5% in the halo margin, and 12.4% ± 16.8% in all 74 detected lesions. The mean increase using unrenormalized SC in SUVmean was 17.5% for lesions inside the halo margin (38 lesions) and 6.9% for lesions outside the halo margin (36 lesions). Conclusion: For PET/MRI of prostate cancer using 68Ga-PSMA, a proper SC is important to ensure the best possible diagnostic quality and PET quantification. Unrenormalized absolute SC significantly reduces the halo artifact around the bladder and improves PET/MRI of the prostate.

Our purpose was to assess the diagnostic potential of simultaneously acquired 18F-FDG PET and MRI data sets for therapy response assessment of isolated limb perfusion (ILP) in patients with soft-tissue sarcomas (STS). Methods: In total, 45 patients with histopathologically verified STS were prospectively enrolled for an integrated 18F-FDG PET/MRI examination before and after ILP. Therapy response was assessed based on different MRI- and PET-derived morphologic (RECIST and the MR-adapted Choi criteria) and metabolic (PERCIST) criteria. In addition, a regression model was used combining relative changes in quantitative variables to predict treatment response under ILP. Histopathologic results after subsequent tumor resection served as the reference standard, and patients were categorized as responders or nonresponders on the basis of the 6-stage regression scale by Salzer-Kuntschik. Results: Histopathologic analysis categorized 27 patients as responders (grades I-III) and 18 patients as nonresponders (grades IV-VI). Calculated sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy were 22%, 89%, 75%, 43%, and 49% for RECIST; 70%, 44%, 66%, 50%, and 60% for the Choi criteria; and 85%, 78%, 85%, 78%, and 82% for PERCIST. Receiver-operating-characteristic analysis revealed an area under the curve (AUC) of 0.56 for RECIST, 0.57 for the Choi criteria, and 0.82 for PERCIST. The combined regression model revealed higher values (AUC, 0.90) than for the stand-alone analysis, however, differences to metabolic parameters did not reach significance (P value: 0.067). Conclusion: Our study demonstrates the superiority of 18F-FDG PET over MRI data sets for response assessment of STS under neoadjuvant ILP. In a clinical setting, MRI delivers valuable information for presurgical assessment. Therefore, combining 18F-FDG PET and MRI data may enable more reliable treatment planning and therapy monitoring of STS.

Ob jectives The European Society of Radiology identified 10 common indications for computed tomography (CT) as part of the European Study on Clinical Diagnostic Reference Levels (DRLs, EUCLID), to help standardize radiation doses. The objective of this study is to generate DRLs and median doses for these indications using data from the UCSF CT International Dose Registry. Methods Standardized data on 3.7 million CTs in adults were collected between 2016 and 2019 from 161 institutions across seven countries (United States of America (US), Switzerland, Netherlands, Germany, UK, Israel, Japan). DRLs (75th percentile) and median doses for volumetric CT-dose index (CTDIvol) and dose-length product (DLP) were assessed for each EUCLID category (chronic sinusitis, stroke, cervical spine trauma, coronary calcium scoring, lung cancer, pulmonary embolism, coronary CT angiography, hepatocellular carcinoma (HCC), colic/abdominal pain, appendicitis), and US radiation doses were compared with European. Results The number of CT scans within EUCLID categories ranged from 8,933 (HCC) to over 1.2 million (stroke). There was greater variation in dose between categories than within categories (p < .001), and doses were significantly different between categories within anatomic areas. DRLs and median doses were assessed for all categories. DRLs were higher in the US for 9 of the 10 indications (except chronic sinusitis) than in Europe but with a significantly higher sample size in the US. Conclusions DRLs for CTDIvol and DLP for EUCLID clinical indications from diverse organizations were established and can contribute to dose optimization. These values were usually significantly higher in the US than in Europe. Key Points • Registry data were used to create benchmarks for 10 common indications for CT identified by the European Society of Radiology. • Observed US radiation doses were higher than European for 9 of 10 indications (except chronic sinusitis). • The presented diagnostic reference levels and median doses highlight potentially unnecessary variation in radiation dose.

Prostate-specific membrane antigen (PSMA)-ligand PET is potentially useful for screening of castration-resistant prostate cancer (CRPC) clinical trial target populations. We investigated the impact of PSMA PET on Prostate Cancer Clinical Trials Working Group 3 (PCWG3) clinical subtype classification when compared with conventional imaging (CI). Methods: A multicenter retrospective study enrolled patients who had undergone PSMA PET for CRPC, had prostate-specific antigen values of at least 1 ng/mL, and had undergone CI-that is, CT plus bone scanning or whole-body MRI. The clinical PCWG3 subtype was determined for PET versus CI by 3 masked readers. Results: Sixty-seven patients were included, and PSMA PET led to up-staging in 15% (10/67) of patients; of these, 6 of 10 (60%) had nonmetastatic CRPC on CI. PSMA PET resulted in down-staging in 15% (10/67) of patients. Agreement for PET versus CI PCWG3 clinical subtypes was 0.81 versus 0.51, 0.74 versus 0.47, 0.95 versus 0.72, or 0.59 versus 0.66 for local, nodal, bone, or visceral disease, respectively. Conclusion: Despite 70% concordance with CI, PSMA PET demonstrated superior reproducibility and accuracy especially for non-metastatic CRPC and should be implemented in future clinical trial entry procedures.

Conventional imaging of low-volume disease (LVD) versus high-volume disease (HVD) is associated with survival in metastatic hormone-sensitive prostate cancer (mHSPC) according to the CHAARTED trial (Chemohormonal Therapy in Metastatic Hormone-Sensitive Prostate Cancer) and the STAMPEDE trial (Systemic Therapy for Advanced or Metastatic Prostate Cancer: Evaluation of Drug Efficacy). We propose a compatible quantitative PSMA PET framework for disease volume assessment in mHSPC. Methods: Three PET centers screened their PSMA PET database for mHSPC patients. CT versus PSMA PET stage, lesion number, and classification of LVD versus HVD were determined by 1 masked reader; PSMA-positive tumor volume was quantified semiautomatically. Results: In total, 85 CT-based CHAARTED LVD and 20 CT-based CHAARTED HVD patients were included. A PSMA tumor volume of about 40 cm(3) was the optimal cutoff between CT-based CHAARTED LVD (nonunifocal) and HVD (non-M1c) (area under the curve, 0.86). Stratification into PET LVD (unifocal or oligometastatic/disseminated < ∼40 cm(3)) and PET HVD (oligometastatic/disseminated ≥ ∼40 cm(3) or M1c) had 13% misalignment with the CHAARTED criteria. Conclusion: PSMA PET criteria with volume quantification deliver comparable LVD/HVD discrimination with additional subgroups for unifocal, oligometastatic, and disseminated disease, critical for guidance of targeted or multimodal therapy.

The low detection rate of conventional imaging and unspecific fluctuations in prostate-specific antigen can hamper early diagnosis of castration-resistant prostate cancer (CRPC). We thus assessed the value of prostate-specific membrane antigen (PSMA) PET/CT in the detection of early CRPC (prostate-specific antigen ≤ 3 ng/mL). Methods: We identified 55 patients with early CRPC from our institutional database. PSMA PET/CT and its CT component were interpreted independently by 3 masked readers. The primary endpoint was the per-patient detection rate; secondary endpoints were interobserver agreement and predictors of PET positivity. Results: PSMA PET/CT was positive in 41 of 55 (75%) patients. Sixteen of 55 (29%) patients had local disease only, and 25 of 55 (45%) had M1 disease. Overall, PSMA PET/CT interobserver agreement was substantial by Landis and Koch criteria (Fleiss κ = 0.77). Conclusion: PSMA PET/CT localized prostate cancer lesions in 75% of patients and M1 disease in 45%. Detection of early CRPC facilitates disease-delaying therapies for local or oligometastatic disease. PSMA PET/CT is of value in early CRPC and should be included in the CRPC entry criteria of the European Association of Urology and Prostate Cancer Working Group 3.

Multiparametric magnetic resonance imaging (mpMRI) and targeted biopsies (TBs) facilitate accurate detection of significant prostate cancer (sPC). However, it remains unclear how many cores should be applied per target.To assess sPC detection rates of two different target-dependent magnetic resonance imaging (MRI)/transrectal ultrasonography (TRUS)-fusion biopsy approaches (TB and target saturation [TS]) compared with extended systematic biopsies (SBs).Retrospective single-centre outcome of transperineal MRI/TRUS-fusion biopsies of 213 men was evaluated. All men underwent TB with a median of four cores per MRI lesion, followed by a median of 24 SBs, performed by experienced urologists. Cancer and sPC (International Society of Urological Pathology grade group ≥2) detection rates were analysed. TB was compared with SB and TS, with nine cores per target, calculated by the Ginsburg scheme and using individual cores of the lesion and its "penumbra".Cancer detection rates were calculated for TS, TB, and SB at both lesion and patient level. Combination of SB + TB served as a reference. Statistical differences in prostate cancer (PC) detection between groups were calculated using McNemar's tests with confidence intervals.TS detected 99% of 134 sPC lesions, which was significantly higher than the detection by TB (87%, p = 0.001) and SB (82%, p0.001). SB detected significantly more of the 72 low-risk PC lesions than TB (99% vs 68%, p0.001) and 10% (p = 0.15) more than that detected by TS. At a per-patient level, 99% of men harbouring sPC were detected by TS. This was significantly higher than that by TB and SB (89%, p = 0.03 and 81%, p = 0.001, respectively). Limitations include limited generalisability, as a transperineal biopsy route was used.TS detected significantly more cases of sPC than TB and extended SB. Given that both 99% of sPC lesions and men harbouring sPC were identified by TS, the results suggest that this approach allows to omit SB cores without compromising sPC detection.Target saturation of magnetic resonance imaging-suspicious prostate lesions provides excellent cancer detection and finds fewer low-risk tumours than the current gold standard combination of targeted and systematic biopsies.

Purpose Apart from the commonly applied manual needle biopsy, CT-guided percutaneous biopsies of bone lesions can be performed with battery-powered drill biopsy systems. Due to assumably different radiation doses and procedural durations, the aim of this study is to examine radiation exposure and establish local diagnostic reference levels (DRLs) of CT-guided bone biopsies of different anatomical regions. Methods In this retrospective study, dose data of 187 patients who underwent CT-guided bone biopsy with a manual or powered drill biopsy system performed at one of three different multi-slice CT were analyzed. Between January 2012 and November 2019, a total of 27 femur (A), 74 ilium (B), 27 sacrum (C), 28 thoracic vertebrae (D) and 31 lumbar vertebrae (E) biopsies were included. Radiation exposure was reported for volume-weighted CT dose index (CTDIvol) and dose–length product (DLP). Results CTDIvol and DLP of manual versus powered drill biopsy were (median, IQR): A: 56.9(41.4–128.5)/66.7(37.6–76.2)mGy, 410(203–683)/303(128–403)mGy·cm, B: 83.5(62.1–128.5)/59.4(46.2–79.8)mGy, 489(322–472)/400(329–695)mGy·cm, C: 97.5(71.6–149.2)/63.1(49.1–83.7)mGy, 627(496–740)/404(316–515)mGy·cm, D: 67.0(40.3–86.6)/39.7(29.9–89.0)mGy, 392(267–596)/207(166–402)mGy·cm and E: 100.1(66.5–162.6)/62.5(48.0–90.0)mGy, 521(385–619)/315(240–452)mGy·cm. Radiation exposure with powered drill was significantly lower for ilium and sacrum, while procedural duration was not increased for any anatomical location. Local DRLs could be depicted as follows (CTDIvol/DLP): A: 91 mGy/522 mGy·cm, B: 90 mGy/530 mGy·cm, C: 116 mGy/740 mGy·cm, D: 87 mGy/578 mGy·cm and E: 115 mGy/546 mGy·cm. The diagnostic yield was 82.4% for manual and 89.4% for powered drill biopsies. Conclusion Use of powered drill bone biopsy systems for CT-guided percutaneous bone biopsies can significantly reduce the radiation burden compared to manual biopsy for specific anatomical locations such as ilium and sacrum and does not increase radiation dose or procedural duration for any of the investigated locations. Level of Evidence Level 3.

To assess serum lactate dehydrogenase (LDH) as a pretreatment prognostic factor in patients with uveal melanoma liver metastases treated with transarterial hepatic chemoperfusion (THC). 56 patients (48 % male, median age: 63.5 years) underwent a median of 4 THC sessions. Kaplan-Meier for median overall survival (OS) and time to hepatic progression (TTP; 95 %CI) in months and Cox proportional hazards model for uni- (UVA)multivariate analyses (MVA) for hazard ratio (HR) evaluation were calculated. The median OS was 9.4 months. The pretreatment LDH value before 1st THC was the strongest OS predictor with 19.8 months for normal (≦ 280 units per liter (U/L)), 9.7 for intermediate ( 280- 1000 U/L), and 3.84 months for high (≧ 1000 U/L) LDH. LDH significantly predicted a median TTP with 8 months, 4 months, and 1 month for normal, intermediate, and high LDH, respectively. UVA revealed intermediate (16.5) and high (77.3) LDH, bilirubin the upper limit of normal (ULN) (2.89), alkaline phosphatase 1.5 ULN (6.8), leukocytes ULN (4.2), gamma-glutamyl transferase (GGT) ULN (7), extrahepatic metastases (1.8) and liver lesions ≥ 5 cm (3.6) as significant predictors for worse OS. MVA confirmed intermediate (5) and high (27.1) LDH, bilirubin (5.7), GGT (2.9), and tumor size ≥ 5 cm (3.7) as significant independent predictors for worse OS. Patients with decreasing vs. increasing LDH 10 % between 1st and 2nd THC (median: 38 days) survived longer (14.6 vs. 4.3 months) and progressed later (7 months vs. 1 month). Elevated pretreatment serum LDH is an essential and robust OS and TTP predictor, potentially allowing for the identification of patients benefiting most from transarterial hepatic chemoperfusion.· Pretherapeutic LDH is the most reliable prognosticator for OS and TTP. · Therapy-related LDH decrease 10 % between 1st and 2nd THC had prolonged OS and TTP. · Lower Values of LDH, bilirubin, gamma-glutamyl transferase, and tumor size are independent pretherapeutic predictors for longer OS. · Extrahepatic metastases do not have an independent influence on overall survival.· Ludwig J, Haubold J, Heusner T et al. Lactate Dehydrogenase Prior to Transarterial Hepatic Chemoperfusion Predicts Survival and Time to Progression in Patients with Uveal Melanoma Liver Metastases. Fortschr Röntgenstr 2021; 193: 683 - 691.ZIEL: Beurteilung der Serum-Laktatdehydrogenase (LDH) als prätherapeutischer prognostischer Faktor bei Patienten mit Lebermetastasen eines Aderhautmelanoms, die mit der transarteriellen hepatischen Chemoperfusion (THC) behandelt wurden. 56 Patienten (48 % männlich, medianes Alter: 63,5 Jahre) erhielten im Median 4 Behandlungen. Die Kaplan-Meier-Analyse für das mediane Gesamtüberleben und die Zeit bis zur hepatischen Tumorprogression (TTP; 95 %-KI) in Monaten sowie das Cox-Proportional-Hazard-Modell für die univariate (UVA) und multivariate Analyse (MVA) zur Bewertung des Risikoquotienten (HR) wurden berechnet. Das mediane Überleben betrug 9,4 Monate. Der LDH-Wert vor der ersten Behandlung war der stärkste Prädiktor für das Überleben mit 19,8 Monaten für normale (≦ 280 Einheiten/Liter (U/L)), 9,7 Monaten für mittlere ( 280– 1000 U/L) und 3,84 Monaten für hohe (≧ 1000 U/L) LDH-Werte. Die LDH war der signifikanteste Vorhersagewert für die TTP mit 8, 4 und 1 Monaten für normale, mittlere bzw. hohe LDH-Werte. Die UVA identifizierte mittlere (16,5) und hohe (77,3) LDH-Werte, Bilirubin Obergrenze des Normalbereichs (ULN) (2,89), alkalische Phosphatase 1,5 ULN (6,8), Leukozyten ULN (4,2), Gamma-Glutamyltransferase (GGT) ULN (7), extrahepatische Metastasen (1,8) und Leberläsionen ≥ 5 cm (3,6) als signifikante Prädiktoren für ein kürzeres Überleben. Die MVA bestätigte mittlere (5,0) und hohe (27,1) LDH-Werte, Bilirubin (5,7), GGT (2,9) und eine Tumorgröße von ≥ 5 cm (3,7) als unabhängige signifikante Prädiktoren für das Überleben. Patienten mit einer LDH-Abnahme vs. einer Zunahme 10 % zwischen der ersten und zweiten Behandlung (median: 38 Tage) überlebten länger (14,6 vs. 4,3 Monate) und zeigten eine spätere Progression (7 vs. 1 Monate). Ein erhöhter prätherapeutischer LDH-Wert ist ein wesentlicher und robuster OS- und TTP-Prädiktor, der es potenziell ermöglicht die Patienten zu identifizieren, welche am meisten von der transarteriellen hepatischen Chemoperfusion profitieren.· Prätherapeutisches LDH ist der stärkste prognostische Faktor für das Überleben und die Tumorprogression. · Eine therapiebedingte LDH-Abnahme 10 % zwischen der ersten und zweiten Behandlung ist mit einem längeren OS und TTP assoziiert. · Niedrigere LDH, Bilirubin und Gamma-Glutamyl-Transferase Werte sowie kleinere Tumore sind unabhängige prätherapeutische Prädiktoren für ein längeres Gesamtüberleben. · Extrahepatische Metastasen haben keinen unabhängigen Einfluss auf das Gesamtüberleben.

Cardiac and liver computed tomography (CT) perfusion has not been routinely implemented in the clinic and requires high radiation doses. The purpose of this study is to examine the radiation exposure and technical settings for cardiac and liver CT perfusion scans at different CT scanners. Two cardiac and three liver CT perfusion protocols were examined with the N1 LUNGMAN phantom at three multi-slice CT scanners: a single-source (I) and second- (II) and third-generation (III) dual-source CT scanners. Radiation doses were reported for the CT dose index (CTDIvol) and dose-length product (DLP) and a standardised DLP (DLP10cm) for cardiac and liver perfusion. The effective dose (ED10cm) for a standardised scan length of 10 cm was estimated using conversion factors based on the International Commission on Radiological Protection (ICRP) 110 phantoms and tissue-weighting factors from ICRP 103. The proposed total lifetime attributable risk of developing cancer was determined as a function of organ, age and sex for adults. Radiation exposure for CTDIvol, DLP/DLP10 cmand ED10 cmduring CT perfusion was distributed as follows: for cardiac perfusion (II) 144 mGy, 1036 mGy·cm/1440 mGy·cm and 39 mSv, and (III) 28 mGy, 295 mGy·cm/279 mGy·cm and 8 mSv; for liver perfusion (I) 225 mGy, 3360 mGy·cm/2249 mGy·cm and 54 mSv, (II) 94 mGy, 1451 mGy·cm/937 mGy·cm and 22 mSv, and (III) 74 mGy, 1096 mGy·cm/739 mGy·cm and 18 mSv. The third-generation dual-source CT scanner applied the lowest doses. Proposed total lifetime attributable risk increased with decreasing age. Even though CT perfusion is a high-dose examination, we observed that new-generation CT scanners could achieve lower doses. There is a strong impact of organ, age and sex on lifetime attributable risk. Further investigations of the feasibility of these perfusion scans are required for clinical implementation.