[Cross-sectional diagnostic imaging in the InEK benchmark : An opportunity for radiology]

Hintergrund

Anhand der vom Institut für das Entgeltsystem im Krankenhaus (InEK) kalkulierten Fallpauschalen ist ein Vergleich der eigenen Leistungsdaten gegenüber allen nach der DRG („diagnosis-related groups“, diagnosebezogene Gruppen) abrechnenden Kliniken in Deutschland möglich. Ziel der vorliegenden Arbeit ist es, Über- oder Unterschreitungen von CT- oder MRT-Untersuchungen im Vergleich mit den InEK-Daten zu ermitteln und mögliche Verbesserungspotenziale zu erschließen.

Methodik

Die InEK-Kalkulationsdaten für 2021 wurden zur Bildung von Vergleichskennzahlen der CT- und MRT-Diagnostik auf DRG-Ebene herangezogen. Auf Fallebene wurden Daten eines universitären Maximalversorgers auf Gesamthaus‑, Klinik‑, DRG- und Hauptdiagnosen-Ebene gegenübergestellt.

Ergebnis

Auf Gesamthausebene zeigt sich eine Überschreitung der MRTs um 1025 und der CTs um 371 gegenüber InEK. Die Analyse nach Fachabteilungen ergab am Beispiel der Neurologie eine Überschreibung der MRTs gegenüber InEK um 489 sowie eine Unterschreitung der CTs um \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$-$$\end{document}-620. Der Benchmark der DRGs zeigte in beiden Untersuchungsmodalitäten insbesondere die DRG B70B als Treiber der Abweichungen (MRT + 42,7; CT − 273). Die identifizierten Abweichungen lassen sich auf Hauptdiagnosen-Ebene weiter herunterbrechen.

Diskussion

Das Bewusstsein über eine überdurchschnittliche Schnittbilddiagnostik kann einen wichtigen Anstoß zur Weiterentwicklung der Behandlungspfade einer Klinik bilden. Die Methodik des InEK-Benchmarks ist für jedes Krankenhaus anwendbar und identifiziert valide bereits erbrachte Leistungen und Prozesse mit einem Verbesserungspotenzial. Die Prüfung beeinflussender Faktoren sowie die Bewertung durch Mediziner und Kaufleute bildet die Voraussetzung für Akzeptanz und Erfolg der daraus generierten Maßnahmen.

Native T1 mapping for differential diagnosis of left ventricular hypertrophy

Funding Acknowledgements

Type of funding sources: None.

Purpose

The aim of this study was to investigate native T1 mapping cardiac magnetic resonance (CMR) tomography for the differential diagnosis of left ventricular (LV) hypertrophy.

Background

Mapping techniques are useful to characterize myocardial tissue abnormalities, particularly cardiac amyloidosis. However, specific cut-off values to differentiate LV hypertrophic phenotypes on 3.0 tesla CMR scanners have not been established, yet.

Methods

We retrospectively identified patients in the CMR database of Leipzig university hospital with increased LV wall thickness (≥12mm diameter at end-diastole) who were referred for the evaluation of LV hypertrophy or ischemia between 2017 and 2020 on a 3T scanner (Philips Achieva). Patients with suspected or confirmed myocarditis were excluded. Diagnosis of cardiac amyloidosis was made by either biopsy or non-invasively by bone scintigraphy and screening for monoclonal gammopathy. T1 mapping was measured as global mean value from 3 short axis slices of the LV.

Results

128 consecutive patients were included in the study. 31 subjects without evidence of structural heart disease served as healthy control. The final diagnosis was cardiac amyloidosis in 24 patients (5 patients with light-chain, 18 with transthyretin amyloidosis, 1 undetermined), hypertrophic cardiomyopathy in 24, and hypertensive heart disease in 80 patients. Mean age of patients was 65 ± 13years, 84% were male. LV mass was increased in patients with LV hypertrophy compared to healthy control (p < 0.001). Native T1 values of the LV myocardium were higher in patients with cardiac amyloidosis (1409 ± 59ms, p < 0.0001 vs. all other groups) compared to healthy control (1225 ± 21ms), patients with hypertrophic cardiomyopathy (HCM; 1263 ± 43ms) and hypertensive heart disease (HHD; 1257 ± 41ms) (Figure). Patients with hypertrophic cardiomyopathy and hypertensive heart disease did not differ in their native T1 values, but both groups were increased compared to healthy control (p < 0.01). Receiver operating characteristic analysis of native T1 values demonstrated an area under the curve for the detection of cardiac amyloidosis of 0.9954 (p < 0.0001) vs. hypertrophic cardiomyopathy, hypertensive heart disease and healthy control. The optimal cut-off value was 1341ms, with a sensitivity of 100% and a specificity of 97%.

Conclusion

Native T1 mapping has high diagnostic accuracy for the diagnosis of cardiac amyloidosis among patients with LV hypertrophy. These data need confirmation in a prospective clinical trial.

Study ID

DRKS00022048

Incidence of incisional hernia after laparoscopic liver resection

BACKGROUND

Minimally invasive techniques have been broadly introduced to liver surgery during the last couple of years. In this study, we aimed to report the incidence and potential risk factors for incisional hernia (IH) as well as health-related quality of life (HRQoL) after laparoscopic liver resections (LLR).

METHODS

All patients undergoing LLR between January 2014 and June 2017 were contacted for an outpatient hernia examination. In all eligible patients, photo documentation of the scar was performed and IH was evaluated by clinical examination and by ultrasound. Patients also completed a questionnaire to evaluate IH-specific symptoms and HRQoL. Obtained results were retrospectively analyzed with regard to patients' characteristics, perioperative outcomes and applied minimally invasive techniques, such as multi-incision laparoscopic liver surgery or hand-assisted/single-incision laparoscopic surgery (HALS/SILS).

RESULTS

Of 184 patients undergoing surgery, 161 (87.5%) met the inclusion criteria and 49 patients (26.6%) participated in this study. After a median time of 26 months (range 19-50 months) after surgery, we observed an overall incidence of IH of 12%. Five of 6 patients were overweight or obese (BMI ≥ 25) and 5 of 6 hernias were located at the umbilical site. Univariate analysis suggested the performance status at time of operation (ASA score ≥ 3; HR 5.616, 95% CI 1.012-31.157, p = 0.048) and the approach (HALS/SILS, HR 6.571, 95% CI 1.097-39.379, p = 0.039) as potential risk factors for IH. A higher frequency of hernia-related physical restrictions (HRR; p = 0.058) and a decreased physical functioning (p = 0.17) were noted in patients with IH; however, both being short of statistical significance.

CONCLUSION

Advantages of laparoscopic surgery with regard to low rates of IH can be translated to minimally invasive liver surgery. Even though there are low rates of IH, patients with poor performance status at the time of operation should be monitored closely. While patients' characteristics are hard to influence, it might be worth focusing on surgical factors such as the approach and the closure of the umbilical site to further minimize the rate of IH.

Hepatocyte Transplantation to the Liver via the Splenic Artery in a Juvenile Large Animal Model

Hepatocyte transplantation (HcTx) is a promising approach for the treatment of metabolic diseases in newborns and children. The most common application route is the portal vein, which is difficult to access in the newborn. Transfemoral access to the splenic artery for HcTx has been evaluated in adults, with trials suggesting hepatocyte translocation from the spleen to the liver with a reduced risk for thromboembolic complications. Using juvenile Göttingen minipigs, we aimed to evaluate feasibility of hepatocyte transplantation by transfemoral splenic artery catheterization, while providing insight on engraftment, translocation, viability, and thromboembolic complications. Four Göttingen Minipigs weighing 5.6 kg to 12.6 kg were infused with human hepatocytes (two infusions per cycle, 1.00E08 cells per kg body weight). Immunosuppression consisted of tacrolimus and prednisolone. The animals were sacrificed directly after cell infusion (n=2), 2 days (n=1), or 14 days after infusion (n=1). The splenic and portal venous blood flow was controlled via color-coded Doppler sonography. Computed tomography was performed on days 6 and 18 after the first infusion. Tissue samples were stained in search of human hepatocytes. Catheter placement was feasible in all cases without procedure-associated complications. Repetitive cell transplantations were possible without serious adverse effects associated with hepatocyte transplantation. Immunohistochemical staining has proven cell relocation to the portal venous system and liver parenchyma. However, cells were neither present in the liver nor the spleen 18 days after HcTx. Immunological analyses showed a response of the adaptive immune system to the human cells. We show that interventional cell application via the femoral artery is feasible in a juvenile large animal model of HcTx. Moreover, cells are able to pass through the spleen to relocate in the liver after splenic artery infusion. Further studies are necessary to compare this approach with umbilical or transhepatic hepatocyte administration.

Gastric neuroendocrine neoplasias: manifestations and comparative outcomes

Although gastric neuroendocrine neoplasias (gNEN) are an orphan disease, their incidence is rising. The heterogeneous clinical course powers the ongoing discussion of the most appropriate classification system and management. Prognostic relevance of proposed classifications was retrospectively analysed in 142 patients from a single tertiary referral centre. Baseline, management and survival data were acquired for statistical analyses. The distribution according to the clinicopathological typification was gNEN-1 (n = 86/60.6%), gNEN-2 (n = 7/4.9%), gNEN-3 (n = 24/16.9%) and gNEN-4 (n = 25/17.6%), while hypergastrinemia-associated gNEN-1 and -2 were all low-grade tumours (NET-G1/2), formerly termed sporadic gNEN-3 could be subdivided into gNEN-3 with grade 1 or 2 and gNEN-4 with grade 3 (NEC-G3). During follow-up 36 patients died (25%). The mean overall survival (OS) of all gNEN was 14.2 years. The OS differed statistically significant across all subgroups with either classification system. According to UICC 2017 TNM classification, OS differed for early and advanced stages, while WHO grading indicated poorer prognosis for NEC-G3. Cox regression analysis confirmed the independent prognostic validity of either classification system for survival. Particularly careful analysis of the clinical course of gNEN-1 (ECLomas, gastric carcinoids) confirmed their mostly benign, but recurrent and extremely slowly progressive behaviour with low risk of metastasis (7%) and an efficient long-term control by repetitive endoscopic procedures. Our study provides evidence for the validity of current classifications focusing on typing, grading and staging. These are crucial tools for risk stratification, especially to differentiate gNEN-1 as well as sporadic gNET and gNEC (gNEN-3 vs -4).

[Surgical strategies for non-metastatic adrenocortical carcinoma]

Adrenocortical carcinomas (ACC) are rare but highly aggressive tumors. It is very difficult to differentiate small locally limited ACCs from benign adenomas. A spontaneous density >10 Hounsfield units in non-enhanced CT scan and a slow washout after contrast injection are suspicious of malignancy but with a low specificity. Preoperatively, a hormonal work-up is mandatory for all adrenal tumors. Each patient should be discussed in an interdisciplinary board. For non-metastatic ACCs (ENSAT stages I-III) radical resection is the treatment of choice. R0-resection and avoiding violation of the tumor capsule are the most important prognostic factors for long-term survival. Although discrepant reports regarding the benefits of lymphadenectomy have been published, lymph node dissection at least in the periadrenal area and in the renal hilum (optional extension to paraaortal and paracaval nodes) should be performed in the case of lymph node involvement. The role of prophylactic lymphadenectomy needs to be analyzed in further studies. The gold standard remains the open approach but minimally invasive procedures are also an option, especially in stage I-II tumors, if the principles of oncological surgery are respected. In this case, long-term survival rates are comparable. As local recurrence rates are lower and time to local recurrence is longer in patients who are operated on at a dedicated center (>10 adrenalectomies/year), adrenalectomy for ACC should be performed by an experienced surgeon.

Determination of ventricular volumes in coronary artery disease

Aim: Comparison of two gated SPECT analysis tools – gated SPECT quantification (GSQ) and emory cardiac toolbox (ECT) – in patients with coronary artery disease (CAD) and severely impaired left ventricular function (preoperative: EF <35% by cardiac catheter). Patients, methods: A total of 56 gatedSPECT examinations (oneday hybrid-protocol with 201Tl-chloride for rest and 99mTcsestamibi for stress applied during low-dose dobutamine stress MR-examination; temporal resolution; 8 phases per cardiac cycle) were performed in 36 patients (31 preoperatively, 25 postoperatively) and compared with MRI in 48 cases. Left ventricular end-diastolic (LV-EDV) and end-systolic (LV-ESV) volumes as well as the left ventricular ejection fraction (LV-EF) were calculated. Results: The total volumetric assessment by both analysis algorithms (n = 56) showed good intraclass correlation coefficients preoperatively (n=31), but even better postoperatively (n=25). The mean reconstruction time was approximately 3 minutes (±2 SD) for GSQ and 15 minutes (±5 SD) for ECT. In comparison to MRI the results of both analysis tools also correlated well, but the agreement decreased in the presence of scared tissue. The mean LV-EF (MRI) preoperatively was 30.4%, in 6/36 patients above the values calculated from cardiac catheter, postoperatively 34.6%. Conclusion: Both gated SPECT analysis tools showed reliable volumetric assessments in high-risk patients with CAD and severely reduced LV-EF in comparison to MRI, with advantages for GSQ in terms of postprocessing time. However, for the calculation of LV-EF a markedly lower concordance with MR-results was observed for both methods depending on the presence of myocardial scars.

Evaluation of patients with liver metastases from colorectal cancer for locally ablative treatment with laser induced thermotherapy

Purpose: Before locally ablative treatment of colorectal liver metastases, patients have to be carefully evaluated to decide whether this is the adequate therapy. In this study we determined the value of FDG-PET in comparison to conventional staging procedures. Patients, methods: In 68 consecutive patients referred for laser induced thermotherapy (LITT) of liver metastases from colorectal cancer, pretherapeutic staging with conventional imaging (thoracic and abdominal CT, liver MRI, chest X-ray) and FDG-PET was performed. The examinations were analysed separately and blinded. Based on the staging information, therapeutic decisions were made by an interdisciplinary review board according to a standardized algorithm. The results were compared between conventional imaging and FDG-PET, and were validated by clinical follow up data and histopathology, respectively. Results: On FDG-PET 210 lesions were interpreted as tumour manifestations. 48 of these were not seen on conventional imaging (true positive, n=46). In contrast, 24 lesions were visualized by conventional imaging only (true positive, n=12). Compared to conventional imaging, discrepant findings on FDG-PET led to treatment modifications in 25 patients (37%); these were correct in 20/25 patients. According to the actual treatment course, the inadequate treatment modifications in the remaining 5 patients were avoided by further diagnostic procedures (i.e. biopsies). Conclusion: In the evaluation of patients with known liver metastases from colorectal cancer before LITT, FDG-PET depicts relevant findings subsidiary to conventional imaging and thus is of high value for therapeutic decision making.

Impact of image fusion and attenuation correction by SPECT-CT on the scintigraphic detection of parathyroid adenomas

Aim: In addition to planar parathyroid scintigraphy, SPECT and image fusion with CT/MR improve adenoma detection in primary hyperparathyroidism (pHPT). This study evaluated the use of a hybrid SPECT-CT device concerning image fusion and attenuation correction (AC). Patients, methods: The data of 26 patients with pHPT, preoperatively examined by 99mTc-sestamibi dual-phase scintigraphy plus SPECT-CT (low-dose CT), was retrospectively evaluated by two observers in a consensus reading. The images of planar scintigraphy, non-attenuation corrected SPECT (SPECTNAC), attenuation corrected SPECT (SPECTAC) and SPECTAC-CT were interpreted and compared to the results of surgery. The effect of AC on focus intensity was semiquantified by determination of the tumor-to-background (TB) ratio for SPECTAC and SPECTNAC. Finally, the TBAC/TBNAC-ratio was calculated for each focus and correlated to the distance of a focus from the body surface. Results: 20/26 (77%) patients were positive in planar scintigraphy. One focus was detected by SPECT only. AC of SPECT-data increased image contrast but had no impact on the detection rate. Additional SPECTAC-CT image fusion facilitated the localization of three mediastinal foci. In the semiquantitative analysis an increase in TB after AC was observed, although there was no strong correlation between depth of the focus (16-60 mm) and the TBAC/TBNAC-ratio (r = 0.213, p = 0.353). Conclusion: The detection rate of planar scintigraphy is only slightly improved by SPECT imaging. Due to the low spatial resolution of the CT component, the benefit of image fusion is limited to mediastinal foci. However, as TB and image contrast is measurably improved after AC there is a potential to improve the sensitivity of parathyroid SPECT.

Incidental detection of breast cancer by 68Ga-DOTATOC-PET/CT in women suffering from neuroendocrine tumours

Aim: Somatostatin receptor (sstr) imaging using 68Ga- DOTATOC-PET/CT in neuroendocrine tumors (NET) is promising, suggesting a more sensitive detection of lesions with a low sstr-expression. This is also important for other sstr positive tumors, especially breast cancer whose incidence and age-range is similar to that of NET. Patients, methods: The PET/CT data of 33 consecutive women with NET (age: 33–78 years, mean 59) who underwent whole-body staging with 68Ga-DOTATOC was retrospectively analyzed for breast lesions. The data was read separately, side-byside and as fused images. Focal tracer uptake in the breast was semiquantitatively analyzed by comparing the lesional SUVmax to normal breast tissue using Wilcoxon's rank sum test. Breast cancer lesions were compared visually to concomitant NET- lesions. Results: In six of 33 patients (18%) breast lesions were observed on the CT-scans and classified in four patients (12%) as suspicious. The same lesions also showed a pathological tracer uptake on the corresponding PET-scan, visually and semiquantitatively (p<0.01). Histological reevaluation of the suspicious lesions revealed two patients with NET metastases. Two patients had primary breast cancer with lower tracer uptake than concomitant abdominal NET-lesions. Breast cancer diagnosis resulted in a change of the therapeutic regimen. Conclusion: 68Ga- DOTATOC-PET/CT not only improves the staging of NET-patients, but also increases the chance to detect sstr-positive breast cancer. Although these lesions may show a lower tracer uptake than NET, they must not be overlooked or misinterpreted as metastases. Further imaging and clarification by histopathology is warranted, as the confirmation of a secondary malignoma has great impact on further therapeutic proceedings.

MRI of cystic fibrosis lung manifestations: sequence evaluation and clinical outcome analysis

AIM

To evaluate different magnetic resonance imaging (MRI) sequences for diagnosis of pulmonary manifestations of cystic fibrosis (CF) in comparison to chest computed tomography (CT), including an extended outcome analysis.

MATERIALS AND METHODS

Twenty-eight patients with CF (15 male, 13 female, mean age 30.5±9.4 years) underwent CT and MRI of the lung. MRI (1.5 T) included different T2- and T1-weighted sequences: breath-hold HASTE (half Fourier acquisition single shot turbo spin echo) and VIBE (volumetric interpolated breath-hold examination, before and after contrast medium administration) sequences and respiratory-triggered PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) sequences with and without fat signal suppression, and perfusion imaging. CT and MRI images were evaluated by the modified Helbich and the Eichinger scoring systems. The clinical follow-up analysis assessed pulmonary exacerbations within 24 months.

RESULTS

The highest concordance to CT was achieved for the PROPELLER sequences without fat signal suppression (concordance correlation coefficient CCC of the overall modified Helbich score 0.93 and of the overall Eichinger score 0.93). The other sequences had the following concordance: PROPELLER with fat signal suppression (CCCs 0.91 and 0.92), HASTE (CCCs 0.87 and 0.89), VIBE (CCCs 0.84 and 0.85) sequences. In the outcome analysis, the combined MRI analysis of all five sequences and a specific MRI protocol (PROPELLER without fast signal suppression, VIBE sequences, perfusion imaging) reached similar correlations to the number of pulmonary exacerbations as the CT examinations.

CONCLUSION

An optimum lung MRI protocol in patients with CF consists of PROPELLER sequences without fat signal suppression, VIBE sequences, and lung perfusion analysis to enable high diagnostic efficacy and outcome prediction.

Computed tomography-based survey of the vascular anatomy of the juvenile Göttingen minipig

Over the past 50 years, image-guided procedures have been established for a wide range of applications. The development and clinical translation of new treatment regimens necessitate the availability of suitable animal models. The juvenile Göttingen minipig presents a favourable profile as a model for human infants. However, no information can be found regarding the vascular system of juvenile minipigs in the literature. Such information is imperative for planning the accessibility of target structures by catheterization. We present here a complete mapping of the arterial system of the juvenile minipig based on contrast-enhanced computed tomography. Four female animals weighing 6.13 ± 0.72 kg were used for the analyses. Imaging was performed under anaesthesia, and the measurement of the vascular structures was performed independently by four investigators. Our dataset forms a basis for future interventional studies in juvenile minipigs, and enables planning and refinement of future experiments according to the 3R (replacement, reduction and refinement) principles of animal research.

[Preoperative imaging/operation planning for liver surgery]

The currently established standard for planning liver surgery is multistage contrast media-enhanced multidetector computed tomography (CM-CT), which as a rule enables an appropriate resection planning, e.g. a precise identification and localization of primary and secondary liver tumors as well as the anatomical relation to extrahepatic and/or intrahepatic vascular and biliary structures. Furthermore, CM-CT enables the measurement of tumor volume, total liver volume and residual liver volume after resection. Under the condition of normal liver function a residual liver volume of 25 % is nowadays considered sufficient and safe. Recent studies in patients with liver metastases of colorectal cancer showed a clear staging advantage of contrast media-enhanced magnetic resonance imaging (CM-MRI) versus CM-CT. In addition, most recent data showed that the use of liver-specific MRI contrast media further increases the sensitivity and specificity of detection of liver metastases. This imaging technology seems to lead closer to the ideal "one stop shopping" diagnostic tool in preoperative planning of liver resection.

Imaging-Based Liver Function Tests--Past, Present and Future

Preoperative assessment of liver function and prediction of postoperative functional reserve are important in patients scheduled for liver resection. While determination of absolute liver function currently mostly relies on laboratory tests and clinical scores, postoperative remnant liver function is estimated volumetrically using imaging data obtained with computed tomography (CT) or magnetic resonance imaging (MRI). Accurate estimation of hepatic function is also relevant for intensive care patients, oncologic patients, and patients with diffuse liver disease. The indocyanine green (ICG) test is still the only established test for estimating true global liver function. However, more recent tools such as the LiMAx test also allow global assessment of hepatic function. These tests are limited when liver function is inhomogeneously distributed, which is the case in such conditions as unilateral cholestasis or after portal vein embolization. Imaging-based liver function tests were first developed in nuclear medicine and, compared with laboratory tests, have the advantage of displaying the spatial distribution of liver function. Nuclear medicine scans are obtained using tracers such as 99mTc galactosyl and 99mTc mebrofenin. Liver function is typically assessed using planar scintigraphy. However, three-dimensional volumetry is possible with single-photon emission computed tomography (SPECT-CT). Another technique for image-based liver function estimation is Gd-EOB-enhanced MRI. While metabolization of Gd-EOB in the body is similar to that of ICG and mebrofenin, its distribution in the liver can be displayed by MRI with higher temporal and spatial resolution. Moreover, MRI-based determination of liver function can be integrated into routine preoperative imaging. This makes MRI an ideal candidate for preoperative determination of liver function, though the best pulse sequence and the parameter to be derived from the image information remain to be identified. Another question to be answered is how the results may be affected by renal function and the presence of hyperbilirubinemia. As more results from clinical evaluation including comparison with postoperative liver function data become available, image-based liver function tests, especially with use of Gd-EOB as the contrast medium, have the potential to add another dimension to preoperative imaging.

KEY POINTS

Liver function consists of a multitude of subfunctions such as biotransformation, excretion and storage. Global liver function tests are score-based tests such as Child-Pugh or MELD as well as the ICG- and LiMAx-test. Imaging-based liver function tests add spatial information. Current clinical standard is the 99mTc-Mebrofenin-scintigraphy. MRI-based function tests with Gd-EOB-DTPA have the potential to integrate seamlessly into clinical workup, feature a higher temporal and spatial resolution and do not rely on ionizing radiation.

Randomized multicentre trial of gadoxetic acid-enhanced MRI versus conventional MRI or CT in the staging of colorectal cancer liver metastases

BACKGROUND

This multicentre international randomized trial compared the impact of gadoxetic acid-enhanced magnetic resonance imaging (MRI), MRI with extracellular contrast medium (ECCM-MRI) and contrast-enhanced computed tomography (CE-CT) as a first-line imaging method in patients with suspected colorectal cancer liver metastases (CRCLM).

METHODS

Between October 2008 and September 2010, patients with suspected CRCLM were randomized to one of the three imaging modalities. The primary endpoint was the proportion of patients for whom further imaging after initial imaging was required for a confident diagnosis. Secondary variables included confidence in the therapeutic decision, intraoperative deviations from the initial imaging-based surgical plan as a result of additional operative findings, and diagnostic efficacy of the imaging modalities versus intraoperative and pathological extent of the disease.

RESULTS

A total of 360 patients were enrolled. Efficacy was analysed in 342 patients (118, 112 and 112 with gadoxetic acid-enhanced MRI, ECCM-MRI and CE-CT respectively as the initial imaging procedure). Further imaging was required in 0 of 118, 19 (17.0 per cent) of 112 and 44 (39.3 per cent) of 112 patients respectively (P < 0.001). Diagnostic confidence was high or very high in 98.3 per cent of patients for gadoxetic acid-enhanced MRI, 85.7 per cent for ECCM-MRI and 65.2 per cent for CE-CT. Surgical plans were changed during surgery in 28, 32 and 47 per cent of patients in the respective groups.

CONCLUSION

The diagnostic performance of gadoxetic acid-enhanced MRI was better than that of CE-CT and ECCM-MRI as the initial imaging modality. No further imaging was needed in the gadoxetic acid-enhanced MRI group and comparison of diagnostic efficacy parameters demonstrated the diagnostic superiority of gadoxetic acid-enhanced MRI.

REGISTRATION NUMBER

NCT00764621(http://clinicaltrials.gov); EudraCT number: 2008-000583-16 (https://eudract.ema.europa.eu/).

Unresectable colorectal liver metastases: percutaneous ablation using CT-guided high-dose-rate brachytherapy (CT-HDBRT)

PURPOSE

To evaluate the clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) of unresectable colorectal liver metastases (CRLMs).

MATERIALS AND METHODS

Retrospective analysis of all consecutive patients with unresectable CRLMs treated with CT-HDRBT between January 2008 and November 2012. Treatment was performed by CT-guided catheter placement and high-dose-rate brachytherapy with an iridium-192 source. MRI follow-up was performed after 6 weeks and then every 3 months post-intervention. The primary endpoint was local tumor control (LTC); secondary endpoints included time to progression (TTP) and overall survival (OS).

RESULTS

80 heavily pretreated patients with 179 metastases were available for MRI evaluation for a mean follow-up time of 16.9 months. The mean tumor diameter was 28.5 mm (range: 8 - 107 mm). No major complications were observed. A total of 23 (12.9 %) local tumor progressions were observed. Lesions ≥ 4 cm in diameter showed significantly more local progression than smaller lesions (< 4 cm). 50 patients (62.5 %) experienced systemic tumor progression. The median TTP was 6 months. 28 (43 %) patients died during the follow-up period. The median OS after ablation was 18 months.

CONCLUSION

CT-HDRBT is an effective technique for the treatment of unresectable CRLMs and warrants promising LTC rates compared to thermal ablative techniques. A combination with other local and systemic therapies should be evaluated in patients with lesions > 4 cm in diameter, in which higher progression rates are expected.

KEY POINTS

• CT-HDRBT enables a highly cytotoxic irradiation of colorectal liver metastases with simultaneous conservation of important neighboring structures (eg liver parenchyma, bile ducts and bowel)• The local tumor control rates obtained by CT-HDRBT in patients with colorectal liver metastases are promising, also compared to the local tumor control rates after RFA• Metastases with a diameter of 4 cm or abow, display a higher local progression rate after CT-HDRBT, therefor a combination therapy with other locoregional or systemic treatments should be investigated in prospective studies.

[Minimal-invasive microwave coagulation therapy for liver tumours: laparoscopic and percutaneous access]

INTRODUCTION

Local ablative treatments play an important role in current surgical treatment strategies. Radiofrequency ablation (RFA) as one of the most popular examples suffers from partly inacceptable local tumour control. Microwave coagulation therapy (MCT) is a comparatively new type of ablation promising several improvements. This series is to the best of our knowledge the first within the central European area, which reports on the successful clinical implementation of MCT in a surgical department.

PATIENTS AND MATERIALS

A novel 915 MHz system (MedWaves™, AveCure Inc., SanDiego, CA/U. S. A.) was used to treat 47 patients with 80 tumour nodules in 51 treatment sessions. Average tumour size was 2.6 ± 0.9 cm. Indications were hepatocellular carcinoma in 29 patients and metastases in 14 as well as 4 cholangiocellular carcinomas. The approach was laparoscopic (20) or percutaneous (31). High-risk conditions defined by unfavourable tumour localisation like invisibility in native transabdominal ultrasound, superficial tumour site or risk of heat sink phenomena were found in 28 cases (53 %).

RESULTS

Local recurrence rate was 17 % on a per-patient and 12 % on a per-tumour basis (n = 9). One patient died because of incurable upper gastrointestinal bleeding during the postoperative hospital stay. No MCT-associated complication occurred. Median follow-up period was 20 months. Local tumour recurrence was significantly different on comparing laparoscopic to percutaneous MCT (p = 0.032, χ2 test), as was global recurrence (p = 0.011, χ2 test). In a univariate logistic Cox regression, tumour size, access and high-risk localisation were significant prognostic factors for local tumour recurrence, however, in a multivariate reiteration, only the chosen access to MCT (p = 0.012) and tumour size (p = 0.044) remain significant.

CONCLUSION

MCT seems to be a useful tool, easy to implement in a surgical environment and may eventually prove to be superior to other local ablative treatment modalities. Even unfavourable tumour localisations could be treated safely and efficiently using MCT without increased risk of local tumour recurrence.

Significant impact of patient age on outcome after liver resection for HCC in cirrhosis

OBJECTIVE

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The majority of patients with HCC have cirrhosis. Beside liver transplantation the resection is an established curative treatment option for patients with HCC in cirrhosis. However, the long term success is limited by a high tumor recurrence rate. Furthermore, by many patients surgical resection is restricted by poor liver function. The purpose of this study was to investigate the influence of patient age on long term outcome after liver resection in patients with HCC in cirrhotic liver. Further purpose was to define the potential prognostic factors.

PATIENTS AND METHODS

The outcome of 141 patients with liver cirrhosis after curative resection was analyzed using a prospective database. Only patients with postoperative histological assurance of HCC were included in the database. Patients with fibrolamellar HCC were excluded.

RESULTS

By patients below 70 years of age the 1-, 3- and 5-year survival rates were 78.5%, 56.5% and 47.1%. By patients over 70 years the 1-, 3- and 5-year survival rates were 59.9%, 40.3% and 6.7%. Cumulative survival of the total collective was significant influenced by patient age, Clavien grade, positive lymph vessels, mechanical ventilation and BMI. The overall postoperative morbidity was 44.7%. No intraoperative deaths were observed, but 11 patients (8 older than 70 and 3 younger than 70 years) died during the hospital stay. Clavien grade correlated with preoperative increased GGT, need for intraoperative blood and fresh frozen plasma transfusion.

CONCLUSIONS

Patient age and postoperative complications are more relevant for the outcome than many tumor factors, especially by patients over 70 years of age. In contrast, the prognosis of patients below 70 years of age is significantly better and a 5 year survival rate above 50% could be shown in our patients. However, by carefully selected elderly patients with HCC in cirrhosis an acceptable long term survival is reachable.

Radiologic resectability assessment in pancreatic cancer

Complete tumor resection is still the only potentially curative therapy option for patients with ductal adenocarcinoma of the pancreas. Surgical exploration is the gold standard for the determination of tumor resectability. Radiological resectability assessment is of great importance because many clearly unresectable cases can be identified preoperatively and it became essential for surgical planning. The evolving surgical and radiological techniques demand a continuous reappraisal of radiological criteria in resectability assessment. In the following, the criteria for resection planning are described along with surgical management and the role of radiology in some innovative surgical concepts is explained.

Percutaneous ablation of lymph node metastases using CT-guided high-dose-rate brachytherapy

OBJECTIVE

To assess the technical feasibility, safety and clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) for achieving local tumour control (LTC) in isolated lymph node metastases.

METHODS

From January 2008 to December 2011, 10 patients (six males and four females) with isolated nodal metastases were treated with CT-HDRBT. Five lymph node metastases were para-aortic, three were at the liver hilum, one at the coeliac trunk and one was a left iliac nodal metastasis. The mean lesion diameter was 36.5 mm (range 12.0-67.0 mm). Patients were followed up by either contrast-enhanced CT or MRI 6 weeks and then every 3 months after the end of treatment. The primary end point was LTC. Secondary end points included primary technical effectiveness rate, adverse events and progression-free survival.

RESULTS

The first follow-up examination after 6 weeks revealed complete coverage of all nodal metastases treated. There was no peri-interventional mortality or major complications. The mean follow-up period was 13.2 months (range 4-20 months). 2 out of 10 patients (20%) showed local tumour progression 9 and 10 months after ablation. 5 out of 10 patients (50%) showed systemic tumour progression. The mean progression-free interval was 9.2 months (range 2-20 months).

CONCLUSION

CT-HDRBT is a safe and effective technique for minimally invasive ablation of nodal metastases.

ADVANCES IN KNOWLEDGE

CT-HDRBT of lymph node metastases is feasible and safe. CT-HDRBT might be a viable therapeutic alternative to obtain LTC in selected patients with isolated lymph node metastases.

Impact of octreotide long-acting release on tumour growth control as a first-line treatment in neuroendocrine tumours of pancreatic origin

BACKGROUND

Somatostatin analogues (SSA) are widely used in the treatment of patients with functioning and non-functioning neuroendocrine tumours (NET). The aim of our investigation was to evaluate the antiproliferative effect of SSA in patients with pancreatic NET.

METHODS

We retrospectively analysed records of 43 patients with pancreatic NET treated at our clinic with octreotide long-lasting release as a first-line therapy. The aim of our study was to investigate the overall best response according to the RECIST criteria, overall best response defined as disease control rate (SD+PR), response and disease control rate at 12 months, and time to tumour progression (TTP).

RESULTS

The mean age (± SD) of the patients (16 female/27 male) at initial diagnosis was 54.7 ± 11.86 years. At the start of therapy, 39 of 43 patients were classified as stage IV according to ENETS-TNM. Tumours were graded, based on MiB-1/Ki67 staining, as G1 (n = 8), G2 (n = 30) or unknown (n = 5). The octreoscan was positive in 37 patients, negative in 2 and unknown in 4 cases. Nineteen patients had functioning tumours, 24 patients had non-functioning tumours. Median overall survival was 98 months, and median TTP was 13 months. Analysis of grading showed a statistically significant influence on TTP when comparing the median TTP for Ki67 >10% with Ki67 <5% (p = 0.009) and Ki67 5-10% (p = 0.036).

CONCLUSION

SSA may be considered as a first-line treatment for antiproliferative purposes in metastatic NET of the pancreas. Patients with a proliferation index <10% displayed a more durable response compared to those with a higher proliferation index.

Morphological analysis and differentiation of benign cystic neoplasms of the pancreas using computed tomography and magnetic resonance imaging

PURPOSE

To evaluate morphologic characteristics and establish a standardized diagnostic algorithm to differentiate benign cystic pancreatic tumors (CPTs) in non-pancreatitis patients using multidetector computed tomography (CT) and magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Patients with histopathologically proven CPTs who had undergone MRI and/or CT and subsequent tumor resection in our institution were retrospectively identified. Images were analyzed for morphology and enhancement patterns by three independent blinded observers. Preoperative image findings were correlated with histopathological results. Based on the evaluated morphologic parameters, a standardized diagnostic algorithm was designed to help characterize the lesions.

RESULTS

A total of 62 consecutive patients with 64 CPTs were identified from the surgical database (21 intraductal papillary mucinous neoplasms; 10 mucinous cystic neoplasms; 12 serous microcystic adenomas; 3 serous oligocystic adenomas; 6 solid pseudopapillary tumors; 12 neuroendocrine neoplasms). The overall averaged accuracy for the 3 observers was 89.9 % for CT and 93.1 % for MRI with increasing overall accuracy in relation to the experience of the observer (88.2 %, 91.5 %, and 93.8 %, respectively). Overall, the generalized kappa value was 0.69 (CT, 0.64; MRI, 0.76); p < 0.001). The accuracy of the standardized diagnostic algorithm was 91.1 %.

CONCLUSION

It is possible to characterize benign CPTs with MRI and CT, while MRI appears to be superior to CT. Diagnostic accuracy depends on the observer's experience. The standardized algorithm can aid in the differential diagnosis but still needs to be tested in other patient populations.