Patterns of radiological response to tebentafusp in patients with metastatic uveal melanoma

Metastatic uveal melanoma (mUM) is a rare type of melanoma with poor outcomes. The first systemic treatment to significantly prolong overall survival (OS) in patients with mUM was tebentafusp, a bispecific protein that can redirect T-cells to gp-100 positive cells. However, the objective response rate according to Response Evaluation Criteria in Solid Tumors (RECIST) may underestimate the clinical impact of tebentafusp. As metabolic response assessed by PET Response Criteria in Solid Tumors (PERCIST) has been reported to better correlate with clinical outcome, we here compared the patterns of radiological and morphological responses in HLA-A*02:01-positive patients with mUM treated with tebentafusp. In the 19 enrolled patients, RECIST showed an overall response rate (ORR) of 10%, median progression-free survival of 2.8 months (95% CI 2.5-8.4), and median OS (mOS) of 18.8 months. In 10 patients, where both RECIST and PERCIST evaluation was available, the ORR was 10% for both; however, the PFS was longer for PERCIST compared to RECIST, 3.1 and 2.4 months, respectively. A poor agreement between the criteria was observed at all assessments (Cohen's kappa ≤0), yet they differed significantly only at the first on-treatment imaging ( P  = 0.037). Elevated baseline LDH and age were associated with an increased risk for RECIST progression, while lymphocyte decrease after the first infusions correlated to reduced risk of RECIST progression. Detectable ctDNA at baseline did not correlate with progression. Early response to tebentafusp may be incompletely captured by conventional imaging, leading to a need to consider both tumor morphology and metabolism.

How Does Target Lesion Selection Affect RECIST? A Computer Simulation Study

OBJECTIVES

Response Evaluation Criteria in Solid Tumors (RECIST) is grounded on the assumption that target lesion selection is objective and representative of the change in total tumor burden (TTB) during therapy. A computer simulation model was designed to challenge this assumption, focusing on a particular aspect of subjectivity: target lesion selection.

MATERIALS AND METHODS

Disagreement among readers and the disagreement between individual reader measurements and TTB were analyzed as a function of the total number of lesions, affected organs, and lesion growth.

RESULTS

Disagreement rises when the number of lesions increases, when lesions are concentrated on a few organs, and when lesion growth borders the thresholds of progressive disease and partial response. There is an intrinsic methodological error in the estimation of TTB via RECIST 1.1, which depends on the number of lesions and their distributions. For example, for a fixed number of lesions at 5 and 15, distributed over a maximum of 4 organs, the error rates are observed to be 7.8% and 17.3%, respectively.

CONCLUSIONS

Our results demonstrate that RECIST can deliver an accurate estimate of TTB in localized disease, but fails in cases of distal metastases and multiple organ involvement. This is worsened by the "selection of the largest lesions," which introduces a bias that makes it hardly possible to perform an accurate estimate of the TTB. Including more (if not all) lesions in the quantitative analysis of tumor burden is desirable.

Early Postoperative Serum Phosphate Drop Predicts Sufficient Hypertrophy After Liver Surgery

OBJECTIVE

The aim of this study was to assess the impact of postoperative hypophosphatemia on liver regeneration after major liver surgery in the scenario of Associating Liver Partition with Portal vein ligation for Staged hepatectomy (ALPPS) and living liver donation (LLD).

BACKGROUND

Hypophosphatemia has been described to reflect the metabolic demands of regenerating hepatocytes. Both ALPPS and LLD are characterized by an exceptionally strong liver regeneration and may be of particular interest in the context of posthepatectomy hypophosphatemia.

METHODS

Serum phosphate changes within the first 7 postoperative days after ALPPS (n=61) and LLD (n=54) were prospectively assessed and correlated with standardized volumetry after 1 week. In a translational approach, postoperative phosphate changes were investigated in mice and in vitro .

RESULTS

After ALPPS stage 1 and LLD, serum phosphate levels significantly dropped from a preoperative median of 1.08 mmol/L [interquartile range (IQR) 0.92-1.23] and 1.07 mmol/L (IQR 0.91-1.21) to a postoperative median nadir of 0.68 and 0.52 mmol/L, respectively. A pronounced phosphate drop correlated well with increased liver hypertrophy ( P <0.001). Patients with a low drop of phosphate showed a higher incidence of posthepatectomy liver failure after ALPPS (7% vs 31%, P =0.041). Like in humans, phosphate drop correlated significantly with degree of hypertrophy in murine ALPPS and hepatectomy models ( P <0.001). Blocking phosphate transporter (Slc20a1) inhibited cellular phosphate uptake and hepatocyte proliferation in vitro.

CONCLUSION

Phosphate drop after hepatectomy is a direct surrogate marker for liver hypertrophy. Perioperative implementation of serum phosphate analysis has the potential to detect patients with insufficient regenerative capacity at an early stage.

Implementing CT tumor volume and CT pleural thickness into future staging systems for malignant pleural mesothelioma

Objectives

Tumor thickness and tumor volume measured by computed tomography (CT) were suggested as valuable prognosticator for patients’ survival diagnosed with malignant pleural mesothelioma (MPM). The purpose was to assess the accuracy of CT scan based preoperatively measured tumor volume and thickness compared to actual tumor weight of resected MPM specimen and pathologically assessed tumor thickness, as well as an analysis of their impact on overall survival (OS).

Methods

Between 09/2013–08/2018, 74 patients were treated with induction chemotherapy followed by (extended) pleurectomy/decortication ((E)PD). In 53 patients, correlations were made between CT-measured volume and -tumor thickness (cTV and cTT) and actual tumor weight (pTW) based on the available values. Further cTV and pT/IMIG stage were correlated using Pearson correlation. Overall survival (OS) was calculated with Kaplan Meier analysis and tested with log rank test. For correlation with OS Kaplan-Meier curves were made and log rank test was performed for all measurements dichotomized at the median.

Results

Median pathological tumor volume (pTV) and pTW were 530 ml [130 ml – 1000 ml] and 485 mg [95 g – 982 g] respectively. Median (IQR) cTV was 77.2 ml (35.0–238.0), median cTT was 9.0 mm (6.2–13.7). Significant association was found between cTV and pTV (R = 0.47, p < 0.001) and between cTT and IMIG stage (p = 0,001) at univariate analysis. Multivariate regression analysis revealed, that only cTV correlates with pTV. Median follow-up time was 36.3 months with 30 patients dead at the time of the analysis. Median OS was 23.7 months. 1-year and 3-year survival were 90 and 26% respectively and only the cTV remained statistically associated with OS.

Conclusion

Preoperatively assessed CT tumor volume and actual tumor volume showed a significant correlation. CT tumor volume may predict pathological tumor volume as a reflection of tumor burden, which supports the integration of CT tumor volume into future staging systems.

Lung Nodules in Melanoma Patients: Morphologic Criteria to Differentiate Non-Metastatic and Metastatic Lesions

Lung nodules are frequent findings in chest computed tomography (CT) in patients with metastatic melanoma. In this study, we assessed the frequency and compared morphologic differences of metastases and benign nodules. We retrospectively evaluated 85 patients with melanoma (AJCC stage III or IV). Inclusion criteria were ≤20 lung nodules and follow-up using CT ≥183 days after baseline. Lung nodules were evaluated for size and morphology. Nodules with significant growth, nodule regression in line with RECIST assessment or histologic confirmation were judged to be metastases. A total of 438 lung nodules were evaluated, of which 68% were metastases. At least one metastasis was found in 78% of patients. A 10 mm diameter cut-off (used for RECIST) showed a specificity of 95% and a sensitivity of 20% for diagnosing metastases. Central location (n = 122) was more common in metastatic nodules (p = 0.009). Subsolid morphology (n = 53) was more frequent (p < 0.001), and calcifications (n = 13) were solely found in non-metastatic lung nodules (p < 0.001). Our data show that lung nodules are prevalent in about two-thirds of melanoma patients (AJCC stage III/IV) and the majority are metastases. Even though we found a few morphologic indicators for metastatic or non-metastatic lung nodules, morphology has limited value to predict the presence of lung metastases.

Development of a Prognostic AI-Monitor for Metastatic Urothelial Cancer Patients Receiving Immunotherapy

Background: Immune checkpoint inhibitor efficacy in advanced cancer patients remains difficult to predict. Imaging is the only technique available that can non-invasively provide whole body information of a patient's response to treatment. We hypothesize that quantitative whole-body prognostic information can be extracted by leveraging artificial intelligence (AI) for treatment monitoring, superior and complementary to the current response evaluation methods.

Methods: To test this, a cohort of 74 stage-IV urothelial cancer patients (37 in the discovery set, 37 in the independent test, 1087 CTs), who received anti-PD1 or anti-PDL1 were retrospectively collected. We designed an AI system [named prognostic AI-monitor (PAM)] able to identify morphological changes in chest and abdominal CT scans acquired during follow-up, and link them to survival.

Results: Our findings showed significant performance of PAM in the independent test set to predict 1-year overall survival from the date of image acquisition, with an average area under the curve (AUC) of 0.73 (p < 0.001) for abdominal imaging, and 0.67 AUC (p < 0.001) for chest imaging. Subanalysis revealed higher accuracy of abdominal imaging around and in the first 6 months of treatment, reaching an AUC of 0.82 (p < 0.001). Similar accuracy was found by chest imaging, 5–11 months after start of treatment. Univariate comparison with current monitoring methods (laboratory results and radiological assessments) revealed higher or similar prognostic performance. In multivariate analysis, PAM remained significant against all other methods (p < 0.001), suggesting its complementary value in current clinical settings.

Conclusions: Our study demonstrates that a comprehensive AI-based method such as PAM, can provide prognostic information in advanced urothelial cancer patients receiving immunotherapy, leveraging morphological changes not only in tumor lesions, but also tumor spread, and side-effects. Further investigations should focus beyond anatomical imaging. Prospective studies are warranted to test and validate our findings.

Outcome of Patients With Severe Aortic Stenosis and Normal Coronary Arteries Undergoing Transcatheter Aortic Valve Implantation

Coronary artery disease and severe aortic stenosis (AS) often coexist. This study sought to investigate the impact of normal coronary arteries as negative risk marker in patients undergoing transcatheter aortic valve implantation (TAVI). Consecutive patients with severe AS undergoing TAVI were dichotomized according to the presence or absence of normal coronary arteries, defined as absence of coronary lesions with diameter stenosis ≥30% in vessels ≥1.5 mm in diameter on coronary angiogram in patients without prior coronary revascularization. The primary end point was 1-year mortality. Out of 987 patients with severe AS undergoing TAVI, 258 (26%) patients had normal coronary arteries. These patients were younger, more likely women, and had lower EuroSCORE II and STS risk scores. Although mortality at 30 days was similar in the normal coronary artery and the coronary atherosclerosis groups (3.1% vs 5.6%, p = 0.11), it was lower in those with normal coronary arteries at 1 year (8.9% vs 17%, p = 0.003). In multivariable analysis, the presence of normal coronary arteries on coronary angiogram independently predicted 1-year mortality (adjusted HR 0.57, 95% CI 0.37 to 0.90, p = 0.02). In conclusion, this study defined normal coronary arteries as negative risk marker in patients with severe AS undergoing TAVI.

Combination of HAI-FUDR and Systemic Gemcitabine and Cisplatin in Unresectable Cholangiocarcinoma: A Dose Finding Single Center Study

BACKGROUND

Unresectable cholangiocarcinoma has a poor prognosis and treatment options are limited. Combined systemic and intrahepatic chemotherapy may improve local control and enable downsizing. The aim of this study was to determine the maximum tolerated dose (MTD) of intravenous gemcitabine combined with intravenous cisplatin and hepatic arterial infusion (HAI) with floxuridine (FUDR) in patients with unresectable intrahepatic or hilar cholangiocarcinoma.

METHODS

Twelve patients were treated within a 3 + 3 dose escalation algorithm with 600, 800, or 1,000 mg/m2 gemcitabine and predefined doses of cisplatin 25 mg/m2 on days 1 and 8, q21, for 4 cycles, and FUDR 0.2 mg/kg on days 1-14 as continuous HAI, q28, for 3 cycles. Safety and toxicity as well as resectability rates after 3 months and preliminary survival data are reported.

RESULTS

The determined MTD for gemcitabine was 800 mg/m2. Dose limiting toxicities were neutropenic fever and biliary tract infections. In total, 27% of the patients showed partial remission and 73% stable disease. Although none of the patients achieved resectability after 3 months, the 3-year overall survival rate was 33%, median overall survival 23.9 months (range 1-49), and median progression-free survival 10.1 months (range 2-40).

CONCLUSIONS

Intravenous gemcitabine/cisplatin plus HAI-FUDR is feasible and appears effective for disease control. Larger prospective studies evaluating this triplet combination are warranted.

Prognostic Value of Deep Learning-Mediated Treatment Monitoring in Lung Cancer Patients Receiving Immunotherapy

BACKGROUND

Checkpoint inhibitors provided sustained clinical benefit to metastatic lung cancer patients. Nonetheless, prognostic markers in metastatic settings are still under research. Imaging offers distinctive advantages, providing whole-body information non-invasively, while routinely available in most clinics. We hypothesized that more prognostic information can be extracted by employing artificial intelligence (AI) for treatment monitoring, superior to 2D tumor growth criteria.

METHODS

A cohort of 152 stage-IV non-small-cell lung cancer patients (NSCLC) (73 discovery, 79 test, 903CTs), who received nivolumab were retrospectively collected. We trained a neural network to identify morphological changes on chest CT acquired during patients' follow-ups. A classifier was employed to link imaging features learned by the network with overall survival.

RESULTS

Our results showed significant performance in the independent test set to predict 1-year overall survival from the date of image acquisition, with an average area under the curve (AUC) of 0.69 (p < 0.01), up to AUC 0.75 (p < 0.01) in the first 3 to 5 months of treatment, and 0.67 AUC (p = 0.01) for durable clinical benefit (6 months progression-free survival). We found the AI-derived survival score to be independent of clinical, radiological, PDL1, and histopathological factors. Visual analysis of AI-generated prognostic heatmaps revealed relative prognostic importance of morphological nodal changes in the mediastinum, supraclavicular, and hilar regions, lung and bone metastases, as well as pleural effusions, atelectasis, and consolidations.

CONCLUSIONS

Our results demonstrate that deep learning can quantify tumor- and non-tumor-related morphological changes important for prognostication on serial imaging. Further investigation should focus on the implementation of this technique beyond thoracic imaging.

Accuracy of Conventional and Machine Learning Enhanced Chest Radiography for the Assessment of COVID-19 Pneumonia: Intra-Individual Comparison with CT

PURPOSE

To evaluate diagnostic accuracy of conventional radiography (CXR) and machine learning enhanced CXR (mlCXR) for the detection and quantification of disease-extent in COVID-19 patients compared to chest-CT.

METHODS

Real-time polymerase chain reaction (rt-PCR)-confirmed COVID-19-patients undergoing CXR from March to April 2020 together with COVID-19 negative patients as control group were retrospectively included. Two independent readers assessed CXR and mlCXR images for presence, disease extent and type (consolidation vs. ground-glass opacities (GGOs) of COVID-19-pneumonia. Further, readers had to assign confidence levels to their diagnosis. CT obtained ≤ 36 h from acquisition of CXR served as standard of reference. Inter-reader agreement, sensitivity for detection and disease extent of COVID-19-pneumonia compared to CT was calculated. McNemar test was used to test for significant differences.

RESULTS

Sixty patients (21 females; median age 61 years, range 38-81 years) were included. Inter-reader agreement improved from good to excellent when mlCXR instead of CXR was used (k = 0.831 vs. k = 0.742). Sensitivity for pneumonia detection improved from 79.5% to 92.3%, however, on the cost of specificity 100% vs. 71.4% (p = 0.031). Overall, sensitivity for the detection of consolidation was higher than for GGO (37.5% vs. 70.4%; respectively). No differences could be found in disease extent estimation between mlCXR and CXR, even though the detection of GGO could be improved. Diagnostic confidence was better on mlCXR compared to CXR (p = 0.013).

CONCLUSION

In line with the current literature, the sensitivity for detection and quantification of COVID-19-pneumonia was moderate with CXR and could be improved when mlCXR was used for image interpretation.

Patterns of organizing pneumonia and microinfarcts as surrogate for endothelial disruption and microangiopathic thromboembolic events in patients with coronavirus disease 2019

BACKGROUND

To evaluate chest-computed-tomography (CT) scans in coronavirus-disease-2019 (COVID-19) patients for signs of organizing pneumonia (OP) and microinfarction as surrogate for microscopic thromboembolic events.

METHODS

Real-time polymerase-chain-reaction (RT-PCR)-confirmed COVID-19 patients undergoing chest-CT (non-enhanced, enhanced, pulmonary-angiography [CT-PA]) from March-April 2020 were retrospectively included (COVID-19-cohort). As control-groups served 175 patients from 2020 (cohort-2020) and 157 patients from 2019 (cohort-2019) undergoing CT-PA for pulmonary embolism (PE) during the respective time frame at our institution. Two independent readers assessed for presence and location of PE in all three cohorts. In COVID-19 patients additionally parenchymal changes typical of COVID-19 pneumonia, infarct pneumonia and OP were assessed. Inter-reader agreement and prevalence of PE in different cohorts were calculated.

RESULTS

From 68 COVID-19 patients (42 female [61.8%], median age 59 years [range 32-89]) undergoing chest-CT 38 obtained CT-PA. Inter-reader-agreement was good (k = 0.781). On CT-PA, 13.2% of COVID-19 patients presented with PE whereas in the control-groups prevalence of PE was 9.1% and 8.9%, respectively (p = 0.452). Up to 50% of COVID-19 patients showed changes typical for OP. 21.1% of COVID-19 patients suspected with PE showed subpleural wedge-shaped consolidation resembling infarct pneumonia, while only 13.2% showed visible filling defects of the pulmonary artery branches on CT-PA.

CONCLUSION

Despite the reported hypercoagulability in critically ill patients with COVID-19, we did not encounter higher prevalence of PE in our patient cohort compared to the control cohorts. However, patients with suspected PE showed a higher prevalence of lung changes, resembling patterns of infarct pneumonia or OP and CT-signs of pulmonary-artery hypertension.

Multimodality imaging derived energy loss index and outcome after transcatheter aortic valve replacement

Aims 

To assess whether the combination of transthoracic echocardiography (TTE) and multidetector computed tomography (MDCT) data affects the grading of aortic stenosis (AS) severity under consideration of the energy loss index (ELI) in patients undergoing transcatheter aortic valve replacement (TAVR).

Methods and results 

Multimodality imaging was performed in 197 patients with symptomatic severe AS undergoing TAVR at the University Hospital Zurich, Switzerland. Fusion aortic valve area index (fusion AVAi) assessed by integrating MDCT derived planimetric left ventricular outflow tract area into the continuity equation was significantly larger as compared to conventional AVAi (0.41 ± 0.1 vs. 0.51 ± 0.1 cm2/m2; P &lt; 0.01). A total of 62 patients (31.4%) were reclassified from severe to moderate AS with fusion AVAi being &gt;0.6 cm2/m2. ELI was obtained for conventional AVAi and fusion AVAi based on sinotubular junction area determined by TTE (ELILTL 0.47 ± 0.1 cm2/m2; fusion ELILTL 0.60 ± 0.1 cm2/m2) and MDCT (ELIMDCT 0.48 ± 0.1 cm2/m2; fusion ELIMDCT 0.61 ± 0.05 cm2/m2). When ELI was calculated with fusion AVAi the effective orifice area was &gt;0.6 cm2/m2 in 85 patients (43.1%). Survival rate 3 years after TAVR was higher in patients reclassified to moderate AS according to multimodality imaging derived ELI (78.8% vs. 67%; P = 0.01).

Conclusion 

Multimodality imaging derived ELI reclassifies AS severity in 43% undergoing TAVR and predicts mid-term outcome.

Volumetric assessment of solid pulmonary nodules on ultralow-dose CT: a phantom study

Background

To reduce the radiation exposure from chest computed tomography (CT), ultralow-dose CT (ULDCT) protocols performed at sub-millisievert levels were previously tested for the evaluation of pulmonary nodules (PNs). The purpose of our study was to investigate the effect of ULDCT and iterative image reconstruction on volumetric measurements of solid PNs.

Methods

CT datasets of an anthropomorphic chest phantom containing solid microspheres were obtained with a third-generation dual-source CT at standard dose, 1/8th, 1/20th and 1/70th of standard dose [CT volume dose index (CTDI_vol): 0.03-2.03 mGy]. Semi-automated volumetric measurements were performed on CT datasets reconstructed with filtered back projection (FBP) and advanced modelled iterative reconstruction (ADMIRE), at strength level 3 and 5. Absolute percentage error (APE) evaluated measurement accuracy related to the effective volume. Scan repetition differences were evaluated using Bland-Altman analysis. Two-way analysis of variance (ANOVA) assessed influence of different scan parameters on APE. Proportional differences (PDs) tested the effect of dose settings and reconstruction algorithms on volumetric measurements, as compared to the standard protocol (standard dose-FBP).

Results

Bland-Altman analysis revealed small mean interscan differences of APE with narrow limits of agreement (-0.1%±4.3% to -0.3%±3.8%). Dose settings (P<0.001), reconstruction algorithms (P<0.001), nodule diameters (P<0.001) and nodule density (P=0.011) had statistically significant influence on APE. Post-hoc Bonferroni tests showed slightly higher APE when scanning with 1/70th of standard dose [mean difference: 3.4%, 95% confidence interval (CI): 2.5-4.3%; P<0.001], and for image reconstruction with ADMIRE5 (mean difference: 1.8%, 95% CI: 1.0-2.5%; P<0.001). No significant differences for scanning with 1/20th of standard dose (P=0.42), and image reconstruction with ADMIRE3 (P=0.19) were found. Scanning with 1/70th of standard dose and image reconstruction with FBP showed the widest range of PDs (-16.8% to 23.4%) compared to standard dose-FBP.

Conclusions

Our phantom study showed no significant difference between nodule volume measurements on standard dose CT (CTDI_vol: 2 mGy) and ULDCT with 1/20th of standard dose (CTDI_vol: 0.10 mGy).

Radiogenomics: bridging imaging and genomics

From diagnostics to prognosis to response prediction, new applications for radiomics are rapidly being developed. One of the fastest evolving branches involves linking imaging phenotypes to the tumor genetic profile, a field commonly referred to as "radiogenomics." In this review, a general outline of radiogenomic literature concerning prominent mutations across different tumor sites will be provided. The field of radiogenomics originates from image processing techniques developed decades ago; however, many technical and clinical challenges still need to be addressed. Nevertheless, increasingly accurate and robust radiogenomic models are being presented and the future appears to be bright.

Peripheral Blood TCR Repertoire Profiling May Facilitate Patient Stratification for Immunotherapy against Melanoma

Many metastatic melanoma patients experience durable responses to anti-PD1 and/or anti-CTLA4; however, a significant proportion (over 50%) do not benefit from the therapies. In this study, we sought to assess pretreatment liquid biopsies for biomarkers that may correlate with response to checkpoint blockade. We measured the combinatorial diversity evenness of the T-cell receptor (TCR) repertoire (the DE₅₀, with low values corresponding to more clonality and lack of TCR diversity) in pretreatment peripheral blood mononuclear cells from melanoma patients treated with anti-CTLA4 (n = 42) or anti-PD1 (n = 38) using a multi-N-plex PCR assay on genomic DNA (gDNA). A receiver operating characteristic curve determined the optimal threshold for a dichotomized analysis according to objective responses as defined by RECIST1.1. Correlations between treatment outcome, clinical variables, and DE₅₀ were assessed in multivariate regression models and confirmed with Fisher exact tests. In samples obtained prior to treatment initiation, we showed that low DE₅₀ values were predictive of a longer progression-free survival and good responses to PD-1 blockade, but, on the other hand, predicted a poor response to CTLA4 inhibition. Multivariate logistic regression models identified DE₅₀ as the only independent predictive factor for response to anti-CTLA4 therapy (P = 0.03) and anti-PD1 therapy (P = 0.001). Fisher exact tests confirmed the association of low DE₅₀ with response in the anti-CTLA4 (P = 0.041) and the anti-PD1 cohort (P = 0.0016). Thus, the evaluation of basal TCR repertoire diversity in peripheral blood, using a PCR-based method, could help predict responses to anti-PD1 and anti-CTLA4 therapies.

The impact of slice-reduced computed tomography on histogram-based densitometry assessment of lung fibrosis in patients with systemic sclerosis

Background

To evaluate usability of slice-reduced sequential computed tomography (CT) compared to standard high-resolution CT (HRCT) in patients with systemic sclerosis (SSc) for qualitative and quantitative assessment of interstitial lung disease (ILD) with respect to (I) detection of lung parenchymal abnormalities, (II) qualitative and semiquantitative visual assessment, (III) quantification of ILD by histograms and (IV) accuracy for the 20%-cut off discrimination.

Methods

From standard chest HRCT of 60 SSc patients sequential 9-slice-computed tomography (reduced HRCT) was retrospectively reconstructed. ILD was assessed by visual scoring and quantitative histogram parameters. Results from standard and reduced HRCT were compared using non-parametric tests and analysed by univariate linear regression analyses.

Results

With respect to the detection of parenchymal abnormalities, only the detection of intrapulmonary bronchiectasis was significantly lower in reduced HRCT compared to standard HRCT (P=0.039). No differences were found comparing visual scores for fibrosis severity and extension from standard and reduced HRCT (P=0.051-0.073). All scores correlated significantly (P<0.001) to histogram parameters derived from both, standard and reduced HRCT. Significant higher values of kurtosis and skewness for reduced HRCT were found (both P<0.001). In contrast to standard HRCT histogram parameters from reduced HRCT showed significant discrimination at cut-off 20% fibrosis (sensitivity 88% kurtosis and skewness; specificity 81% kurtosis and 86% skewness; cut-off kurtosis ≤26, cut-off skewness ≤4; both P<0.001).

Conclusions

Reduced HRCT is a robust method to assess lung fibrosis in SSc with minimal radiation dose with no difference in scoring assessment of lung fibrosis severity and extension in comparison to standard HRCT. In contrast to standard HRCT histogram parameters derived from the approach of reduced HRCT could discriminate at a threshold of 20% lung fibrosis with high sensitivity and specificity. Hence it might be used to detect early disease progression of lung fibrosis in context of monitoring and treatment of SSc patients.

Impact of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) on growth of colorectal liver metastases

BACKGROUND

Associating liver partition and portal vein ligation for staged hepatectomy induces an unprecedented liver hypertrophy and enables resection of otherwise unresectable liver tumors. The effect of associating liver partition and portal vein ligation for staged hepatectomy on tumor proliferation, however, remains a concern. This study investigated the impact of associating liver partition and portal vein ligation for staged hepatectomy on growth of colorectal metastases in mice and in humans.

METHODS

The effect of associating liver partition and portal vein ligation for staged hepatectomy and 90% portal vein ligation on colorectal liver and lung metastases was investigated in mice. In vivo tumor progression was assessed by magnetic resonance imaging, histology, and survival experiments. The effects of associating liver partition and portal vein ligation for staged hepatectomy, portal vein ligation, and control sera on cultures of several colorectal cancer cell lines (MC38 and CT26) were tested in vitro. Additionally, the international associating liver partition and portal vein ligation for staged hepatectomy registry enabled us to identify patients with remaining tumor in the future liver remnant after associating liver partition and portal vein ligation for staged hepatectomy stage 1.

RESULTS

Two and 3 weeks after associating liver partition and portal vein ligation for staged hepatectomy stage 1, portal vein ligation, or sham surgery, liver magnetic resonance images showed similar numbers (P=.14/0.82), sizes (P=.45/0.98), and growth kinetics (P=.58/0.68) of intrahepatic tumor. Tumor growth was not different between the associating liver partition and portal vein ligation for staged hepatectomy and portal vein ligation groups after completion of stage 2. Median survival after tumor cell injection was similar after sham surgery (36 days; 95% confidence interval; 27-57 days), completion of associating liver partition and portal vein ligation for staged hepatectomy (42 days; 95% confidence interval; 35-49 days), and portal vein ligation (39 days; 95% confidence interval; 34-43 days, P=.237). Progression of pulmonary metastases and in vitro cell proliferation were comparable among groups. Observations in humans failed to identify any accelerated tumor growth in the future liver remnant within the regenerative phase after associating liver partition and portal vein ligation for staged hepatectomy stage 1.

CONCLUSION

The accelerated regeneration process associated with associating liver partition and portal vein ligation for staged hepatectomy does not appear to enhance growth of colorectal metastases.

Circulating complement component 4d (C4d) correlates with tumor volume, chemotherapeutic response and survival in patients with malignant pleural mesothelioma

Only limited information is available on the role of complement activation in malignant pleural mesothelioma (MPM). Thus, we investigated the circulating and tissue levels of the complement component 4d (C4d) in MPM. Plasma samples from 55 MPM patients, 21 healthy volunteers (HV) and 14 patients with non-malignant pleural diseases (NMPD) were measured by ELISA for C4d levels. Tissue specimens from 32 patients were analyzed by C4d immunohistochemistry. Tumor volumetry was measured in 20 patients. We found no C4d labeling on tumor cells, but on ectopic lymphoid structures within the tumor stroma. Plasma C4d levels did not significantly differ between MPM, HV or NMPD. Late-stage MPM patients had higher plasma C4d levels compared to early-stage (p = 0.079). High circulating C4d was associated with a higher tumor volume (p = 0.047). Plasma C4d levels following induction chemotherapy were significantly higher in patients with stable/progressive disease compared to those with partial/major response (p = 0.005). Strikingly, patients with low C4d levels at diagnosis had a significantly better overall survival, confirmed in a multivariate cox regression model (hazard ratio 0.263, p = 0.01). Our findings suggest that circulating plasma C4d is a promising new prognostic biomarker in patients with MPM and, moreover, helps to select patients for surgery following induction chemotherapy.

Phase I study of a chloroquine-gemcitabine combination in patients with metastatic or unresectable pancreatic cancer

PURPOSE

Following a previously published pre-clinical validation, this phase I study evaluated the safety, maximum tolerated dose, anti-tumour activity and immune status of a gemcitabine-chloroquine combination as a first- or late-line treatment in patients with metastatic or unresectable pancreatic cancer.

METHODS

In this 3 + 3 dose escalation study, patients received a single weekly standard dose of intravenous gemcitabine, followed by single weekly oral intake of 100, 200 or 300 mg of chloroquine. Tumour response was assessed using the Response Evaluation Criteria in Solid Tumors version 1.1. Immune status was evaluated by RT-PCR to measure the relative expression of immune-related genes in peripheral blood mononuclear cells (PBMCs).

RESULTS

Overall, nine patients [median age 72 years; interquartile range (IQR), 68-78 years] were treated. No dose-limiting toxicities as defined in the protocol were observed. Three patients experienced partial response, and two patients had stable disease. The median time to progression was 4 months (95% CI 0.8-7.2), and the median overall survival was 7.6 months (95% CI 5.3-9.9). Among 86 assayed immune genes, three were significantly differentially expressed in PBMCs from responding versus non-responding patients: interferon-gamma receptor-1, toll-like receptor 2, and beta-2 microglobulin.

CONCLUSIONS

The addition of chloroquine to gemcitabine was well tolerated and showed promising effects on the clinical response to the anti-cancer chemotherapy. Based on these initial results, the efficacy of the gemcitabine-chloroquine combination should be further assessed.

Computed tomography-based three-dimensional visualisation of bone corridors and trajectories for screws in open reduction and internal fixation of symphysis diastasis: a retrospective radiological study

INTRODUCTION

Typical stabilisation of pelvic open book injuries consists of plate fixation of the symphysis. No previous literature has been published about the evaluation of screw placement and their trajectory with four oblique 4.5 mm screws using a four-hole plate in symphysis diastasis. The aim of this study was to define insertion points and angles of trajectory for crossed screw placement regardless of any plate design based on an analysis of three-dimensional computed tomography data sets.

METHODS

One hundred human pelvic CT data sets were collected. Unilateral and bilateral placements of crossed 4.5 mm screws were simulated. Primary outcome measure was successful simulated screw placement without cortical breach. Secondary outcome measures included the anatomical measurements of the screw positions.

RESULTS

Simulated screw placement of two oblique screws on each side of the pubic symphysis without cortical breach was achieved in all (100 %) cases. There were a total of 400 screw simulations. Medial screws were longer, lateral screws had higher coronal angles, and the distance between both screws was higher on the right side (p < 0.001 each). The lengths of the right lateral, right medial, left lateral, and left medial screws were 44.9, 65.8, 45.4, and 67.4 mm, respectively. The sagittal angles to the dorsal surface area of the pubic rami were 10.5°, 11.1°, 9.0°, and 11.0°. The coronal angles to the vertical axis of the symphysis measured 39.5°, 16.0°, 33.8°, and 16.8°. The distances between these screws and the medial edge of the pubic crest were 33.5, 8.6, 29.5, and 7.3 mm. Furthermore, certain sex- and side-related differences were noted.

CONCLUSIONS

This series provides results about the feasibility and a detailed anatomical description of crossed screw placement. This is of special interest in pelvic surgery for choosing the entry points, safe screw channel parameters, and trajectories.

How much liver needs to be transected in ALPPS? A translational study investigating the concept of less invasiveness

BACKGROUND

ALPPS induces rapid liver hypertrophy after stage-1 operation, enabling safe, extended resections (stage-2) after a short period. Recent studies have suggested that partial transection at stage-1 might be associated with a better safety profile. The aim of this study was to assess the amount of liver parenchyma that needs to be divided to achieve sufficient liver hypertrophy in ALPPS.

METHODS

In a bi-institutional, prospective cohort study, nonfibrotic patients who underwent ALPPS with complete (n = 22) or partial (n = 23) transection for colorectal liver metastases were analyzed and compared with an external ALPPS cohort (n = 23). A radiologic tool was developed to quantify the amount of parenchymal transection. Liver hypertrophy and clinical outcome were compared between both techniques. The relationship of partial transection and hypertrophy was investigated further in an experimental murine model of partial ALPPS.

RESULT

The median amount of parenchymal transection in partial ALPPS was 61% (range, 34-86%). The radiologic method correlated poorly with the intraoperative surgeon's estimation (r_S = 0.258). Liver hypertrophy was equivalent for the partial ALPPS, ALPPS, and external ALPPS cohort (64% vs 60% vs. 64%). Experimental data demonstrated that partial transection of at least 50% induced comparable hypertrophy (137% vs 156%) and hepatocyte proliferation compared to complete transection.

CONCLUSION

The study provides clinical and experimental evidence that partial liver partition of at least 50% seems to be equally effective in triggering volume hypertrophy as observed with complete transection and can be re recommended as less invasive alternative to ALPPS.

Treatment of isolated ascending aortic aneurysm by off-pump epiaortic wrapping is safe and durable

OBJECTIVES

Isolated ascending aortic aneurysm (iAA) is usually treated by open graft repair requiring sternotomy, cardiopulmonary bypass (CPB) and cardioplegia. This approach carries significant mortality in older patients or those presenting with comorbidities. We report an original series of patients presenting with iAA and treated with epiaortic wrapping by using a synthetic mesh. This less invasive aortic repair technique allows reducing the aortic diameter to a predefined value and is performed without CPB.

METHODS

Data from patients presenting with an iAA and treated with the wrapping technique (WT) by polypropylene/polyester mesh from November 2006 to July 2015 were collected. The end-points that were analysed included maximal aortic transverse diameter, perioperative mortality and morbidity, survival, freedom from reinterventions and aortic valve function during follow-up. The maximal aneurysm transverse diameter was analysed based on contrast-enhanced computed tomography (CTA) or magnetic resonance (MR) performed preoperatively, and during the follow-up.

RESULTS

The off-pump WT was used in 33 cases with no perioperative mortality. The median radiological follow-up was 33.47 (range: 1-106) months. Overall, the WT achieved a 30% diameter reduction. The mean preoperative and postoperative ascending aortic transverse diameter was 5.5 cm [standard deviation (SD): 0.6] and 3.7 cm (SD: 0.30), respectively (P = 0.001). In addition, CTA or MR follow-up showed stable diameters at the level of the aortic root and the distal ascending aorta. No death occurred during the follow-up. At 5 years, the estimated freedom rate from reinterventions of the aortic root and ascending aorta was 94%.

CONCLUSIONS

This series shows that the WT with a polypropylene/polyester mesh allows safe off-pump treatment of patients with iAA. Mid- and long-term results are promising. This technique could be an attractive alternative, especially for patients unfit for aortic surgery with CPB and cardioplegia.

Correlation of pelvic incidence with radiographical parameters for acetabular retroversion: a retrospective radiological study

Background

Pelvic incidence (PI) has been linked to several degenerative processes within the spinopelvic system. Acetabular retroversion is a recognised risk factor for osteoarthritis of the hip. We therefore hypothesised that these two factors might be part of a specific anatomical variant associated with degenerative changes. This study was performed to clarify this issue.

Methods

The pelvic incidence was measured on 589 computertomographical data sets acquired between 2008 and 2010. For 220 patients a 2D rendering in an antero-posterior view of the CT data set was performed to evaluate the parameters of acetabular retroversion. Those included the prominence of the ischial spine sign (PRISS), the cross-over sign (COS) and the posterior wall sign (PWS). Between 477 and 478 hips were evaluated depending on the parameter of retroversion.

Results

The mean pelvic incidence was significantly lower in hips positive for the PRISS and the PWS. However, there were no significant differences between hips positive or negative for the COS.

Discussion

As hypothesised, the lower PI values in PWS and PRISS positive hips suggest a link between PI and retroversion of the acetabulum. Whether this is of any clinical relevance remains, however, unknown.

Conclusion

Acetabular retroversion is linked to PI. In hips where the prominence of the ischial spine sign and/or the posterior wall sign was present, the mean pelvic incidence value was lower.

Urinary biomarkers at early ADPKD disease stage

Background

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by a decline in renal function at late disease stage when the majority of functional renal parenchyma is replaced by cystic tissue. Thus, kidney function, assessed by estimated glomerular filtration rate (eGFR) does not well represent disease burden in early disease. Here, we investigated various urinary markers for tubular injury and their association with disease burden in ADPKD patients at early disease course.

Methods

ADPKD patients between 18 and 40 years with an eGFR greater or equal to 70 ml per min per 1.73m² were eligible for this cross-sectional study. Urinary Neutrophil Gelatinase-Associated Lipocalin (NGAL), Kidney Injury Molecule-1 (KIM-1), and Uromodulin (UMOD) were investigated by Enzyme-Linked Immunosorbent Assay. Clara Cell Protein 16 (CC16) was investigated by Latex Immuno Assay. Cryoscopy was performed to assess urine osmolality and Urinary Albumin-to-Creatinine Ratio (UACR) was calculated. The association and the predictive properties of the markers on eGFR and height adjusted total kidney volume (htTKV) was evaluated using multiple regression analysis, incorporating different control variables for adjustment. Internal bootstrapping validated the obtained results.

Results

In 139 ADPKD patients (age 31 ±7 years, mean eGFR of 93 ± 19 ml per min per 1.73 m²) the total kidney volume was negatively correlated with eGFR and UMOD and positive associated with age, UACR, KIM-1 and urine osmolality after adjustment for possible confounders. Urine osmolality and htTKV were also associated with eGFR, whereas no association of CC16, NGAL and UMOD with eGFR or htTKV was found.

Conclusion

UACR and urinary KIM-1 are independently associated with kidney size but not with renal function in our study population. Urine osmolality was associated with eGFR and kidney volume following adjustment for multiple confounders. Despite statistical significance, the clinical value of our results is not yet conceivable. Further studies are needed to evaluate the property of the aforementioned biomarkers to assess disease state at early ADPKD stage.

Prosthesis-Specific Predictors of Paravalvular Regurgitation after Transcatheter Aortic Valve Replacement: Impact of Calcification and Sizing on Balloon-Expandable versus Self-Expandable Transcatheter Heart Valves

BACKGROUND AND AIM OF THE STUDY

The study aim was to investigate prosthesis-specific predictors for paravalvular aortic regurgitation (PAR) in self-expandable versus balloon-expandable transcatheter heart valves (THVs). PAR is frequently observed after transcatheter aortic valve replacement (TAVR). As self-expandable and balloon-expandable THVs engage differently with the native aortic valve structures, factors that impact PAR may differ between the prosthesis types.

METHODS

A total of 137 TAVR patients who underwent pre-procedural multidetector computed tomography and post-procedural transthoracic echocardiography were studied. Predictors for PAR, including annulus area oversizing and aortic valve calcification mass and volume, were analyzed in a multivariate model.

RESULTS

The Medtronic CoreValve (MCV) prosthesis was utilized in 68 patients (50%), and the Edwards SAPIEN (ES) prosthesis in 69 (50%). More than mild PAR was observed in 43 patients (32%). Among MCV patients, aortic valve calcification volume and mass were higher in those with more than mild PAR than in those with none or mild PAR (p = 0.04, p = 0.03, respectively). Among ES patients, the annulus area and perimeter oversizing were lower in those with more than mild PAR compared to those with no or mild PAR (p = 0.001). By univariate and multivariate logistic regression analysis, aortic valve calcification mass was the only independent predictor for PAR in MCV patients (p = 0.02), whereas in ES patients it was THV undersizing (p = 0.002), irrespective of the calcific burden.

CONCLUSION

For self-expandable THVs, aortic valve calcification mass was the strongest predictor of PAR, whereas for balloon-expandable THVs it was prosthesis undersizing. Hence, in patients evaluated for TAVR these parameters should guide the selection of prosthesis type.

Transcatheter aortic valve-in-valve implantation: clinical outcome as defined by VARC-2 and postprocedural valve dysfunction according to the primary mode of bioprosthesis failure

OBJECTIVES

The objectives of this study were to investigate: (1) the clinical outcome of transcatheter aortic valve-in-valve (VIV) implantation according to Valve Academic Research Consortium (VARC)-2 criteria; and (2) to determine whether postprocedural transvalvular gradients differ in patients with bioprosthesis regurgitation or stenosis as primary mode of failure.

BACKGROUND

Transcatheter aortic VIV implantation has become a feasible option for selected high-risk patients with failed aortic surgical bioprostheses.

METHODS

Transcatheter aortic VIV implantation was performed in 14 high-risk individuals at the University of Zurich and University College London.

RESULTS

The prosthesis was successfully implanted in 13 patients (93%). In 1 patient, a second transcatheter valve needed to be implanted due to valve malpositioning. Thirty-day all-cause mortality was 7% (1/14). Prosthetic valve dysfunction according to VARC-2 at 30 days was observed in 7/14 patients (50%) due to an increased postprocedural transvalvular gradient >20 mm Hg. Preprocedural transaortic gradients correlated significantly with postprocedural gradients (r=0.91; P<.001). At 30-day follow-up, postprocedural gradients were higher in patients with aortic stenosis as primary mode of failure as compared to those with aortic regurgitation (36 ± 6 mm Hg vs 16 ± 4 mm Hg; P=.01). None of the patients exhibited prosthetic valve regurgitation of more than mild degree.

CONCLUSION

The feasibility and safety of VIV implantation in failed aortic bioprostheses is demonstrated. A higher postprocedural gradient was observed after VIV implantation in patients with aortic stenosis as compared to regurgitation as primary mode of failure.

Efficacy of anti-fungal but not anti-bacterial prophylaxis in intensive primary AML therapy: a real-world, retrospective comparative single-centre study

QUESTIONS UNDER STUDY

The optimal strategy of anti-infectious prophylaxis in patients with acute leukaemia undergoing intensive chemotherapy remains a matter of debate. We assessed the impact of primary prophylaxis with posaconazole and levofloxacin on the incidence of invasive fungal infections (IFI) and bacteraemia.

METHODS

A retrospective single-centre study including two groups of adult patients with AML receiving intensive chemotherapy. Group one without anti-infective prophylaxis (September 2008 - February 2010), and group two with anti-infective prophyalaxis (March 2010 - April 2011). The primary end-point was IFI according to the EORTC/MSG 2008 definitions and bacteraemia.

RESULTS

Baseline characteristics were similar in the non-prophylaxis (n = 43 patients; 99 chemotherapy cycles) and the prophylaxis (n = 45; 104 chemotherapy cycles) group. IFI were significantly reduced in the prophylaxis group (55.3% vs. 88.9%; p = 0.0032) and there was a trend of the projected IFI-free survival at 100 days to be increased (50.1% vs. 25%; p = 0.0526). One-hundred day overall survival (84.4% and 88.4%, p = 0.35) and 2-year overall survival (64.4% and 58.1%; p = 0.64) were unaffected. No difference in the occurrence of bacteraemia was observed (32.3% vs. 34.6%; p = 0.8). A total of two (3.6%) patients in the non-prophylaxis and three (6.7%) in the prophylaxis group died due to IFI, and two (3.6%) in the non-prophylaxis and none in the prophylaxis group patients had to stop leukaemia treatment due to IFI.

CONCLUSIONS

The anti-infective prophylaxis with posaconazole and levofloxacin resulted in a significant reduction of 'possible' IFI with a number-needed to treat to prevent one IFI of only 3 but did not result in a reduction of the incidence of bacteraemia.

Increased pelvic incidence may lead to arthritis and sagittal orientation of the facet joints at the lower lumbar spine

BACKGROUND

Correct sagittal alignment with a balanced pelvis and spine is crucial in the management of spinal disorders. The pelvic incidence (PI) describes the sagittal pelvic alignment and is position-independent. It has barely been investigated on CT scans. Furthermore, no studies have focused on the association between PI and facet joint (FJ) arthritis and orientation. Therefore, our goal was to clarify the remaining issues about PI in regard to (1) physiologic values, (2) age, (3) gender, (4) lumbar lordosis (LL) and (5) FJ arthritis and orientation using CT scans.

METHODS

We retrospectively analyzed CT scans of 620 individuals, with a mean age of 43 years, who presented to our traumatology department and underwent a whole body CT scan, between 2008 and 2010. The PI was determined on sagittal CT planes of the pelvis by measuring the angle between the hip axis to an orthogonal line originating at the center of the superior end plate axis of the first sacral vertebra. We also evaluated LL, FJ arthritis and orientation of the lumbar spine.

RESULTS

596 individuals yielded results for (1) PI with a mean of 50.8°. There was no significant difference for PI and (2) age, nor (3) gender. PI was significantly and linearly correlated with (4) LL (p = < 0.0001). Interestingly, PI and (5) FJ arthritis displayed a significant and linear correlation (p = 0.0062) with a cut-off point at 50°. An increased PI was also significantly associated with more sagitally oriented FJs at L5/S1 (p = 0.01).

CONCLUSION

PI is not correlated with age nor gender. However, this is the first report showing that PI is significantly and linearly associated with LL, FJ arthritis and more sagittal FJ orientation at the lower lumbar spine. This may be caused by a higher contact force on the lower lumbar FJs by an increased PI. Once symptomatic or in the event of spinal trauma, patients with increased PI and LL could benefit from corrective surgery and spondylodesis.

Evaluation of calcium loss after transcatheter aortic valve implantation

OBJECTIVES

Aortic valve calcification and changes after transcatheter aortic valve implantation (TAVI) were specifically assessed by computed tomography (CT). The main difference between TAVI and the conventional technique is the compression of the cusps of the calcified native valve against the aortic wall before implantation. The objective of this study was to quantify the segmented calcification in the area of the basal annular plane before and after TAVI.

METHODS

The CT scans of 20 patients (13 male and 7 female; mean age: 82.9 ± 8.1 years) were assessed. The aortic valve calcification was segmented; derived from this segmentation volume, mass and Hounsfield units (HU)/density of the calcifications on the annulus and cusps before and after TAVI were evaluated. Pre- and postoperative data were compared regarding potential calcification loss and calcification distances to the left and right coronary ostia.

RESULTS

Significantly lower postprocedural mean volumes and masses for all cusps (P < 0.001) were found. The mean differences in the volume for the non-coronary, right-coronary and left-coronary cusp were -156.8 ± 53.73, -155.5 ± 62.54 and -115 ± 57.53 mm(3), respectively, and differences in mass were -88.78 ± 29.48, -95.2 ± 39.27 and -71.56 ± 35.62 mg, respectively. Over all cusps, mean HU increased after intervention [784.41 ± 92.5 HU (pre) and 818.63 ± 78.71 HU (post); P < 0.004]. In 80.03% of all cusps, calcification loss was found; all patients were affected. Significantly lower (P < 0.047) postprocedural mean distances were found from the left and right coronary ostia to the next calcification point.

CONCLUSIONS

Our results show a significant loss of calcification in all patients after TAVI, with a reduction in the calcification distances to the coronary ostia and the compression of calcification in the area of the device landing zone. The clinical implications of this finding need to be investigated further.