Cäcilia S. Reiner

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 surgeons estimation (rS = 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.

Direct comparison of PI-RADS version 2 and version 1 regarding interreader agreement and diagnostic accuracy for the detection of clinically significant prostate cancer

PURPOSE to simultaneously evaluate interreader agreement and diagnostic accuracy in the of PI-RADS v2 and compare it to v1. METHODS A total of 67 patients (median age 65.3 y, range 51.2-78.2 y; PSA 6.8μg/L, 0.2-33μg/L) undergoing MRI of the prostate and subsequent transperineal template biopsy within ≤6 months from MRI were included. Four readers from two institutions evaluated the likelihood of prostate cancer using PI-RADS v1 and v2 in two separate reading sessions ≥3 months apart. Interreader agreement was assessed for each pulse-sequence and for total PI-RADS scores using the intraclass correlation coefficient (ICC). Differences were considered significant for non-overlapping 95%-confidence intervals. Diagnostic accuracy was assessed with the area under the receiver operating characteristic curve (AZ). A p-value <0.05 was considered statistically significant. RESULTS Interreader agreement for DCE-scores was good in v2 (ICC2=0.70; 95% CI: 0.66-0.74) and slightly lower in v1 (ICC1=0.64, 0.59-0.69). Agreement for DWI scores (ICC1=0.77, ICC2=0.76) as well as final PI-RADS scores per quadrant were nearly identical (ICC1=ICC2=0.71). Diagnostic accuracy showed no significant differences (p=0.09-0.93) between v1 and v2 in any of the readers (range: AZ=0.78-0.88). CONCLUSION PI-RADS scores show similar interreader agreement in v2 and v1 at comparable diagnostic performance. The simplification of the DCE interpretation in v2 might slightly improve agreement while not negatively affecting diagnostic performance.

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.

MRI and PET-CT Failed to Differentiate Between Hepatic Malignancy and Brucelloma

Abstract Brucellosis is a common, worldwide zoonosis. Clinical presentation is protean and often goes unrecognized. Hepatic brucelloma is a rare local complication of chronic brucellosis. We report a case in which magnetic resonance imaging and positron emission tomography imaging prompted suspicion of a hepatic malignancy. Diagnosis was ultimately made by serology and polymerase chain reaction of resected liver tissue.

Simultaneous Multislice Diffusion-Weighted Imaging of the Kidney: A Systematic Analysis of Image Quality.

Objectives The aims of this study were to implement a protocol for simultaneous multislice (SMS) accelerated diffusion-weighted imaging (DWI) of the kidneys and to perform a systematic analysis of image quality of the data sets. Materials and Methods Ten healthy subjects and 5 patients with renal masses underwent DWI of the kidney in this prospective institutional review board–approved study on a 3 T magnetic resonance scanner. Simultaneous multislice DWI echo-planar sequences (acceleration factors [AFs] 2 and 3) were compared with conventional echo-planar DWI as reference standard for each acquisition scheme. The following 3 acquisition schemes were applied: comparison A, with increased number of acquisitions at constant scan time; comparison B, with reduction of acquisition time; and comparison C, with increased slice resolution (constant acquisition time, increasing number of slices). Interreader reliability was analyzed by calculating the intraclass correlation coefficient (ICC). Qualitative image quality features were evaluated by 2 independent radiologists on a 5-point Likert scale. Quantification accuracy of the apparent diffusion coefficients (ADCs) and signal-to-noise ratios (SNRs) were assessed by region of interest analysis. Furthermore, lesion conspicuity in the 5 patients was assessed using a 5-point Likert scale by 2 independent radiologists. Results Interreader agreement was substantial with an ICC of 0.68 for the overall image quality and an ICC of 0.73 for the analysis of artifacts. In comparison A, AF2 resulted in increased SNR (P < 0.05) by 21% at stable image quality scores (image quality: P = 0.76, artifacts: P = 0.21). In comparison B, applying AF2, the scan time could be reduced by 46% without significant reduction in qualitative image quality scores (P = 0.059) or SNR (P = 0.126). In comparison C, slice resolution could be improved by 28% using AF2 with stable image quality scores and SNR. In general, AF3 resulted in reduced image quality and SNR. Significantly reduced ADC values were observed for AF3 in comparison C (cortex: P = 0.003; medulla: P = 0.001) compared with the standard echo-planar imaging sequence. The conventional DWI and the SMS DWI with AF2 showed stable lesion conspicuity ([AF1/AF2]: reader 1 [1.8/1.4] and reader 2 [1.8/1.4]). The lesion conspicuity was lower using AF3 (reader 1: 2.2 and reader 2: 1.8). Conclusions In conclusion, SMS DWI of the kidney is a potential tool to substantially reduce scan time without negative effects on SNR, ADC quantification accuracy, and image quality if an AF2 is used. Although AF3 results in even higher scan time reduction, a negative impact on image quality, SNR, ADC quantification accuracy, and lesion conspicuity must be considered.