Probing structural features in potato starch granules at moderate hydration through the modelling of 1H->13C polarization transfer kinetics.

The structural arrangement of starch polymers in presence of water is known to impact the functional properties of starchy products. In this study, the hydration of potato starch granules was investigated at the molecular level through various 1H->13C polarization transfer solid-state Nuclear Magnetic Resonance (ss-NMR) experiments. The impact of increasing the water content from 12.3 % to 45.9 % was assessed using 13C Cross Polarization Magic Angle Spinning (CPMAS), Variable Contact Time (VCT-CPMAS), Variable Spin Lock (VSL-CPMAS), and T One Rho QUEnching (TORQUE) NMR sequences. Of these, VCT-CPMAS proved to be the most promising. When applied with an optimal number of contact times, it enabled the application of several mathematical models that provided detailed insights into the structuring of protons in the hydrated potato starch granules. At low hydration (12.3 %), the models enabled various structural domains to be distinguished, which we suggest are associated with helical and amorphous structures. At moderate hydration (45.9 %), we tested two fitting models. Two pools of protons were revealed, corresponding to loosely ordered structures on the scale of tens of nanometers. These findings suggest varying water distribution during starch hydration and are likely to indicate variable hydration levels in the multilamellar amorphous structures of starch granules.

Investigating locations of recurrences with MRI after CRS-HIPEC for colorectal peritoneal metastases.

PURPOSE: Patients with colorectal peritoneal metastases (PM) treated with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are at high risk of recurrent disease. Understanding where and why recurrences occur is the first step in finding solutions to reduce recurrence rates. Although diffusion-weighted (DW) MRI is not routinely used in the follow-up of CRC patients, it has a clear advantage over CT in detecting the location and spread of (recurrent) PM. This study aimed to identify common locations of recurrence in CRC patients after CRS-HIPEC with MRI. METHOD: This was a single-centre retrospective study of patients with recurrent PM after CRS-HIPEC performed between January 2016 and August 2020. Patients were eligible for inclusion if they had both an MRI preoperatively (MRI1) and at the time of recurrent disease (MRI2). Two abdominal radiologists reviewed in consensus and categorized recurrences according to their location on MRI2 and in correlation with previous disease location on prior imaging (MRI1) and the surgical report of the CRS-HIPEC. RESULTS: Thirty patients were included, with a median surgical PCI of 7 (range 3-21) at the time of primary CRS-HIPEC. In total, 68 recurrent metastases were detected on MRI2, of which 14 were extra-peritoneal. Of the remaining 54 PM, 42 (78%) occurred where the peritoneum was damaged due to earlier resections or other surgical procedures (e.g. inserted surgical abdominal drains). Most recurrent metastases were found in the mesentery, lower abdomen/pelvis and abdominal wall (87%). CONCLUSIONS: Most recurrent PMs appeared in the mesentery, lower abdomen/pelvis and abdominal wall, especially where the peritoneum was previously damaged.

Polysaccharide-water interactions: NMR and DVS data.

The data provided here relate to the research paper "Assessing the complementarity of TD-NMR, solid-state NMR and Dynamic Vapor Sorption in the characterization of polysaccharide-water interactions". The original data from TD-NMR, ss-NMR and DVS is provided in .dps, topspin and .xls formats respectively, allowing other authors to repeat our processing protocols using different parameters. We also include results obtained by varying the signal treatments. The analysis of these multimodal data have highlighted a variation in polysaccharide-water interactions depending on the type of assembly. These datasets are very useful for discriminating between water bound to polysaccharides and water absorbed or adsorbed into polysaccharide network, a key element in understanding interactions in these assemblies and an essential approach for developing tailor-made polysaccharides-based products.

Assessing the complementarity of time domain NMR, solid-state NMR and dynamic vapor sorption in the characterization of polysaccharide-water interactions.

Characterizing the hygroscopic behavior of macromolecular assemblies is crucial for understanding biological processes as well as to develop tailor-made polysaccharides-based products. In this work, assemblies consisting of nanocelluloses (CNC or CNF) and/or glucomannan in different ratio were studied at different water activity levels, using a multi-analytical approach that combined Dynamic Vapor Sorption (DVS), Time-Domain Nuclear Magnetic Resonance (TD-NMR) and solid-state NMR (ss-NMR). The water retention capacity of the films, as a function of their composition, showed that an enrichment in konjac glucomannan in association with cellulose increased the water absorption capacity but decreased the water retention capacity. In addition, the combination of CNC and glucomannan appears to reduce the water absorption capacity of each polymer. Correlating the findings from the various methods allowed us to propose the use of TD-NMR data for predicting the water retention capacity. These results, summarized in a schematic representation, offer new insights into the organization of water molecules in polysaccharide assemblies in various humidity conditions.

Optimization of acquisition and processing times for the measurement of 1H to 13C polarization transfer kinetics.

Solid-state NMR (ssNMR) is a unique technique allowing the study of macromolecular assemblies in their native state without prior modification. The proposed method simplifies the current long and tedious data-acquisition and processing protocols for Variable Contact Time (VCT) ssNMR experiments used in dynamic studies of macromolecular assemblies. Using cellulose nanocrystals as a model for polysaccharide assembly, the acquisition time was reduced by decreasing the number of scans and shortening the recycling time required for the 1H to 13C polarization transfers.•A tenfold reduction in the acquisition time for each kinetic point was achieved while maintaining a good signal to noise ratio.•The processing time for the pseudo-2D solid-state NMR data was also shortened by using signal intensities derived from peak picking rather than the classically-used spectral deconvolution method.•These optimizations enabled the molecular dynamic parameters T1ρ H, THH, TCH to be accessed within a day.

Assessment of cellulose interactions with water by ssNMR: 1H->13C transfer kinetics revisited.

To evaluate cellulose interactions with water, 1H->13C polarization transfer kinetics during Variable Contact Time CP-MAS NMR spectroscopy were studied and modelled using cellulose of different origins. The increase in the temporal resolution of the plot relating signal intensity to contact-time made it possible to compare different physical models for use in fitting the kinetic curve. These models involve combinations of variables, such as proton spin diffusions, that require a better understanding of their physicochemical and structural bases. To that end, hydrogen interactions were modulated by adding water, first by varying cellulose water content, second by exchanging hydroxyl protons with D2O, and last by varying the spinning rate. The results demonstrate that this approach makes it possible to probe interactions of polysaccharides with structural water, as well as to follow the evolution of the proton-proton interactions during hydration through spin diffusion times.

Peroperative extent of peritoneal metastases affects the surgical outcome and survival in advanced ovarian cancer.

OBJECTIVE: Determining whether cytoreductive surgery (CRS) is feasible in patients with advanced ovarian cancer and whether extensive surgery is justified is challenging. Accurate patient selection for CRS based on pre- and peroperative parameters will be valuable. The aim of this study is to assess the association between the extent of peritoneal metastases as determined during surgery and completeness of interval CRS and survival. METHODS: This single-center observational cohort study included consecutive patients with newly diagnosed stage III-IV epithelial ovarian cancer who received neoadjuvant chemotherapy and underwent interval CRS. The 7 Region Count (7RC) was recorded during surgical exploration to systematically quantify the extent of peritoneal metastases. Logistic regression analysis was performed to predict surgical outcomes, and Cox regression analysis was done for survival outcomes. RESULTS: A total of 316 patients were included for analyses. The median 7RC was 4 (interquartile range: 2-6). Complete CRS was performed in 58%, optimal CRS in 30%, and incomplete CRS in 12% of patients. A higher 7RC was independently associated with lower odds of complete or optimal CRS in multivariable analysis (odds ratio [OR] = 0.45, 95% confidence interval [CI]: 0.33-0.63, p < 0.001). Similarly, a higher 7RC was independently associated with worse progression-free survival (hazard ratio [HR] = 1.17, 95% CI 1.08-1.26, p < 0.001) and overall survival (HR = 1.14, 95% CI 1.04-1.25, p = 0.007). CONCLUSION: The extent of peritoneal metastases, as expressed by the 7RC during surgery, is an independent predictor for completeness of CRS and has independent prognostic value for progression-free survival and overall survival in addition to completeness of CRS.

Percutaneous cryoablation: a novel treatment option in non-visceral metastases of the abdominal cavity after prior surgery.

PURPOSE: To assess the primary safety and oncological outcome of percutaneous cryoablation in patients with non-visceral metastases of the abdominal cavity after prior surgery. METHODS: All patients with non-visceral metastases after prior abdominal surgery, treated with percutaneous cryoablation, and at least one year of follow-up were retrospectively identified. Technical success was achieved if the ice-ball had a minimum margin of 10 mm in three dimensions on the per-procedural CT images. Complications were recorded using the Society of Interventional Radiology (SIR) classification system. Time until disease progression was monitored with follow-up CT and/or MRI. Local control was defined as absence of recurrence at the site of ablation. RESULTS: Eleven patients underwent cryoablation for 14 non-visceral metastases (mean diameter 20 ± 9 mm). Primary tumor origin was renal cell (n = 4), colorectal (n = 3), granulosa cell (n = 2), endometrium (n = 1) and appendix (n = 1) carcinoma. Treated metastases were localized retroperitoneal (n = 8), intraperitoneal (n = 2), or in the abdominal wall (n = 4). Technical success was achieved in all procedures. After a median follow-up of 27 months (12-38 months), all patients were alive. Local control was observed in 10/14 non-visceral metastases, and the earliest local progression was detected after ten months. No major adverse events occurred. One patient suffered a minor asymptomatic adverse event. CONCLUSION: This proof-of-concept study suggests that cryoablation can be a minimal invasive treatment option in a selected group of patients with non-visceral metastases in the abdominal cavity after prior surgery.

Diagnostic performance of MRI for staging peritoneal metastases in patients with colorectal cancer after neoadjuvant chemotherapy.

INTRODUCTION: MRI improves the selection of patients with colorectal cancer (CRC) and peritoneal metastases (PM) for cytoreductive surgery by accurately assessing the extent of PM reflected as the peritoneal cancer index (PCI). The performance of MRI after neoadjuvant chemotherapy (NACT) for staging PM, however is unknown. The purpose of this study was to determine whether MRI could also accurately determine the PCI after NACT. MATERIALS AND METHODS: This was a single-centre, retrospective study of patients with PM from CRC or appendiceal origin who received NACT followed by diffusion-weighted (DW)-MRI and surgery from January 2016 to February 2021. Two radiologists assessed the PCI on restaging DW-MRI (mriPCI). The reference standard was the surgical PCI (sPCI). The main outcome was the diagnostic performance of restaging DW-MRI in predicting whether patients were eligible for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), defined as a PCI < 21 with metastases on resectable locations. If CRS-HIPEC was performed, the resected peritoneal lesions were assessed and correlated with the final pathological PCI (pPCI). RESULTS: Thirty-three patients were included. Both readers correctly detected all 23 patients with resectable disease. Eight out of ten patients with unresectable disease during staging surgery were detected by both readers with MRI. The intraclass correlation (ICC) between both readers was excellent (0⋅87 (95% CI: 0⋅75 to 0⋅93)). The ICC between pPCI and mriPCI was 0⋅74 (0⋅49-0⋅88) and 0⋅82 (0⋅66-0⋅91) for the 2 readers. Surgical PCI (sPCI) had a similar correlation as mriPCI with pPCI 0⋅82 (0⋅62- 0⋅92)) and 0⋅81 (0⋅57-0⋅92)). CONCLUSION: DW-MRI is a promising tool to reassess the peritoneal cancer index after neoadjuvant chemotherapy.

Seeing the whole picture: Added value of MRI for extraperitoneal findings in CRS-HIPEC candidates.

PURPOSE: In colorectal cancer (CRC) patients the selection of suitable cytoreductive surgery and hyperthermic peritoneal chemotherapy (CRS-HIPEC) candidates is based on the location and extent of peritoneal metastases (PM) and presence of extraperitoneal metastases. MRI is increasingly being used to accurately assess the extent of PM, however, the significance of extraperitoneal findings in these scans has never been evaluated before. METHODS: CRC patients who had undergone an additional MRI scan after standard work-up with CT for preoperative staging between January 2016-January 2020 were selected. CT and MRI reports were reviewed for new abdominopelvic extra-peritoneal findings on MRI (MR-EPF) and MR-EPFs concerning lesions previously indicated as equivocal (uncertain benign/malignant) on CT. Reference standard were surgical results or follow-up imaging. RESULTS: In 158 included patients 60 MR-EPFs (in 58/158 patients) were noted: twenty-six (43%) were new findings and thirty-four (57%) were equivocal findings on CT. Of the 34 equivocal findings 27 were 'rejected/less likely malignant' and 7 'confirmed/more likely malignant' based on MRI. In 29 patients (18%) the MR-EPFs had direct influence on treatment planning. Three patients (2%), eligible for CRS-HIPEC on CT, were deemed inoperable due to MR-EPFs. CONCLUSION: MRI had an added value in more than a third of the patients due to abdominopelvic extraperitoneal findings that were undetected or indeterminate on CT and therefore influenced the treatment in a substantial part of the patients. Combined with the known accurate detection of peritoneal disease on MRI, MRI seems a logical addition to the diagnostic workup of potential CRS-HIPEC candidates.

Peroperative scoring systems for predicting the outcome of cytoreductive surgery in advanced-stage ovarian cancer - A systematic review.

The extent of peritoneal metastases (PM) largely determines the possibility of complete or optimal cytoreductive surgery in advanced ovarian cancer. An objective scoring system to quantify the extent of PM can help clinicians to decide whether or not to embark on CRS. Therefore several scoring systems have been developed by different research teams and this review summarizes their performance in predicting a complete or optimal cytoreduction in patients with advanced ovarian cancer. A systematic search in the MEDLINE database revealed 19 articles that described a total of five main scoring systems to predict the completeness of CRS in patients with FIGO stage III-IV ovarian cancer based on the surgical exploration of the abdominal cavity; PCI, PIV, Eisenkop, Espada, and Kasper. The Peritoneal Cancer Index (PCI) and the Predictive Index Value (PIV) were mentioned most frequently and showed AUCs of 0.69-0.92 and 0.66-0.98, respectively. Due to the use of different cut-offs sensitivities and specificities greatly varied. Therefore with the current data, no scoring system could be identified as best. An objective measure of the extent of disease can be of great clinical use for identifying ovarian cancer patients for which a complete (or optimal) CRS is achievable, however due to local differences in treatment strategies and surgical policy a widely adopted objective scoring system with a standard cut-off value is not feasible. Nevertheless, objective scoring systems can play an important role to guide treatment decisions.

Dedicated MRI staging versus surgical staging of peritoneal metastases in colorectal cancer patients considered for CRS-HIPEC; the DISCO randomized multicenter trial.

BACKGROUND: Selecting patients with peritoneal metastases from colorectal cancer (CRCPM) who might benefit from cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is challenging. Computed tomography generally underestimates the peritoneal tumor load. Diagnostic laparoscopy is often used to determine whether patients are amenable for surgery. Magnetic resonance imaging (MRI) has shown to be accurate in predicting completeness of CRS. The aim of this study is to determine whether MRI can effectively reduce the need for surgical staging. METHODS: The study is designed as a multicenter randomized controlled trial (RCT) of colorectal cancer patients who are deemed eligible for CRS-HIPEC after conventional CT staging. Patients are randomly assigned to either MRI based staging (arm A) or to standard surgical staging with or without laparoscopy (arm B). In arm A, MRI assessment will determine whether patients are eligible for CRS-HIPEC. In borderline cases, an additional diagnostic laparoscopy is advised. The primary outcome is the number of unnecessary surgical procedures in both arms defined as: all surgeries in patients with definitely inoperable disease (PCI > 24) or explorative surgeries in patients with limited disease (PCI < 15). Secondary outcomes include correlations between surgical findings and MRI findings, cost-effectiveness, and quality of life (QOL) analysis. CONCLUSION: This randomized trial determines whether MRI can effectively replace surgical staging in patients with CRCPM considered for CRS-HIPEC. TRIAL REGISTRATION: Registered in the clinical trials registry of U.S. National Library of Medicine under NCT04231175 .

Plasma tumor gene conversions after one cycle abiraterone acetate for metastatic castration-resistant prostate cancer: a biomarker analysis of a multicenter international trial.

BACKGROUND: Plasma tumor DNA fraction is prognostic in metastatic cancers. This could improve risk stratification before commencing a new treatment. We hypothesized that a second sample collected after one cycle of treatment could refine outcome prediction of patients identified as poor prognosis based on plasma DNA collected pre-treatment. PATIENTS AND METHODS: Plasma DNA [128 pre-treatment, 134 cycle 2 day 1 (C2D1), and 49 progression] from 151 chemotherapy-naive metastatic castration-resistant prostate cancer (mCRPC) patients in a phase II study of abiraterone acetate (NCT01867710) were subjected to custom targeted next-generation sequencing covering exons of these genes: TP53, AR, RB1, PTEN, PIK3CA, BRCA1, BRCA2, ATM, CDK12, CHEK2, FANCA HDAC2 and PALB2. We also captured 1500 pan-genome regions enriched for single nucleotide polymorphisms to allow detection of tumor DNA using the rolling B-allele method. We tested associations with overall survival (OS) and progression-free survival (PFS). RESULTS: Plasma tumor DNA detection was associated with shorter OS [hazard ratio (HR): 2.89, 95% confidence intervals (CI): 1.77-4.73, P ≤ 0.0001] and PFS (HR: 2.05; 95% CI: 1.36-3.11, P < 0.001). Using a multivariable model including plasma tumor DNA, patients who had a TP53, RB1 or PTEN gene alteration pre-treatment and at C2D1 had a significantly shorter OS than patients with no alteration at either time point (TP53: HR 7.13, 95% CI 2.37-21.47, P < 0.001; RB1: HR 6.24, 95% CI 1.97-19.73, P = 0.002; PTEN: HR 11.9, 95% CI 3.6-39.34, P < 0.001). Patients who were positive pre-treatment and converted to undetectable had no evidence of a difference in survival compared with those who were undetectable pre-treatment (P = 0.48, P = 0.43, P = 0.5, respectively). Progression samples harbored AR gain in all patients who had gain pre-treatment (9/49) and de novo AR somatic point mutations were detected in 8/49 patients. CONCLUSIONS: Plasma gene testing after one cycle treatment refines prognostication and could provide an early indication of treatment benefit.

Roadmap on quantum nanotechnologies.

Quantum phenomena are typically observable at length and time scales smaller than those of our everyday experience, often involving individual particles or excitations. The past few decades have seen a revolution in the ability to structure matter at the nanoscale, and experiments at the single particle level have become commonplace. This has opened wide new avenues for exploring and harnessing quantum mechanical effects in condensed matter. These quantum phenomena, in turn, have the potential to revolutionize the way we communicate, compute and probe the nanoscale world. Here, we review developments in key areas of quantum research in light of the nanotechnologies that enable them, with a view to what the future holds. Materials and devices with nanoscale features are used for quantum metrology and sensing, as building blocks for quantum computing, and as sources and detectors for quantum communication. They enable explorations of quantum behaviour and unconventional states in nano- and opto-mechanical systems, low-dimensional systems, molecular devices, nano-plasmonics, quantum electrodynamics, scanning tunnelling microscopy, and more. This rapidly expanding intersection of nanotechnology and quantum science/technology is mutually beneficial to both fields, laying claim to some of the most exciting scientific leaps of the last decade, with more on the horizon.

Diagnostic performance of imaging for the detection of peritoneal metastases: a meta-analysis.

PURPOSE: Detection of peritoneal metastases (PM) is key in the staging and management of gastrointestinal and ovarian cancer patients. The purpose of this meta-analysis was to determine the diagnostic performance of CT, PET(CT), and (DW)MRI in detecting PM. METHODS: A literature search in Pubmed, Embase (Ovid), and Scopus was performed (January 1997-May 2018) to identify studies reporting on the accuracy of imaging PM in the diagnostic workup of gastrointestinal or ovarian cancers. Inclusion criteria were region-based or patient-based studies comprising > 15 patients, surgery/histology/radiological follow-up as a reference standard, and sufficient data to construct a 2 × 2 contingency table. Two observers performed data extraction. The sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated using a bivariate random-effects model and hierarchical summary operating curves (HSROC) were generated. RESULTS: Of 3457 citations retrieved, twenty-four articles met all inclusion criteria. Thirty-seven datasets could be extracted for analysis including 20 for CT, 10 for PET(CT), and 7 for (DW)MRI. The pooled sensitivity, specificity, and DOR for the detection of PM for region-based studies for CT were 68% (CI, 46-84%), 88%(CI, 81-93%), and 15.9 (CI, 4.4-58.0) respectively; 80% (CI, 57-92%), 90% (CI, 80-96%), and 36.5 (CI, 6.7-199.5) for PET(CT), respectively; 92% (CI, 84-96%), 85% (CI, 78-91%), 63.3 (CI, 31.5-127.3) for (DW)MRI. In the patient-based group, not enough studies were included to make a pooled analysis for (DW)MRI and PET(CT). CONCLUSION: (DW)MRI and PET(CT) showed comparable diagnostic performance for the detection of peritoneal metastases in ovarian and gastrointestinal cancer patients. Since MRI is more widely available than PET(CT) in clinical practice, this potentially is the imaging method of choice in most centers in the future. KEY POINTS: • Detection of peritoneal metastases plays an important role in the accurate staging of cancer patients, however, there is no accepted reference standard for the imaging of peritoneal metastases • This meta-analysis shows that (DW)MRI provided the highest sensitivity for the detection of peritoneal metastases in ovarian and gastrointestinal cancer patients • Although (DW)MRI and PET(CT) show a comparable overall diagnostic performance, (DW)MRI seems to be the imaging method of choice since it is more available in daily practice than PET(CT).

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy versus palliative systemic chemotherapy in stomach cancer patients with peritoneal dissemination, the study protocol of a multicentre randomised controlled trial (PERISCOPE II).

BACKGROUND: At present, palliative systemic chemotherapy is the standard treatment in the Netherlands for gastric cancer patients with peritoneal dissemination. In contrast to lymphatic and haematogenous dissemination, peritoneal dissemination may be regarded as locoregional spread of disease. Administering cytotoxic drugs directly into the peritoneal cavity has an advantage over systemic chemotherapy since high concentrations can be delivered directly into the peritoneal cavity with limited systemic toxicity. The combination of a radical gastrectomy with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has shown promising results in patients with gastric cancer in Asia. However, the results obtained in Asian patients cannot be extrapolated to Western patients. The aim of this study is to compare the overall survival between patients with gastric cancer with limited peritoneal dissemination and/or tumour positive peritoneal cytology treated with palliative systemic chemotherapy, and those treated with gastrectomy, CRS and HIPEC after neoadjuvant systemic chemotherapy. METHODS: In this multicentre randomised controlled two-armed phase III trial, 106 patients will be randomised (1:1) between palliative systemic chemotherapy only (standard treatment) and gastrectomy, CRS and HIPEC (experimental treatment) after 3-4 cycles of systemic chemotherapy.Patients with gastric cancer are eligible for inclusion if (1) the primary cT3-cT4 gastric tumour including regional lymph nodes is considered to be resectable, (2) limited peritoneal dissemination (Peritoneal Cancer Index < 7) and/or tumour positive peritoneal cytology are confirmed by laparoscopy or laparotomy, and (3) systemic chemotherapy was given (prior to inclusion) without disease progression. DISCUSSION: The PERISCOPE II study will determine whether gastric cancer patients with limited peritoneal dissemination and/or tumour positive peritoneal cytology treated with systemic chemotherapy, gastrectomy, CRS and HIPEC have a survival benefit over patients treated with palliative systemic chemotherapy only. TRIAL REGISTRATION: clinicaltrials.gov NCT03348150 ; registration date November 2017; first enrolment November 2017; expected end date December 2022; trial status: Ongoing.

MRI with diffusion-weighted imaging to predict feasibility of complete cytoreduction with the peritoneal cancer index (PCI) in advanced stage ovarian cancer patients.

OBJECTIVES: To determine the diagnostic performance of MRI with diffusion-weighted imaging (DW-MRI) in assessing the peritoneal tumor load and predicting whether a complete cytoreduction can be achieved in patients with epithelial ovarian cancer (EOC). METHODS: For this observational prospective study, 25 patients with epithelial ovarian cancer scheduled for cytoreductive surgery were included. Patients underwent a 3 T DW-MRI scan prior to surgery. The MR protocol consisted of a T1 and T2 weighted, a contrast-enhanced T1 weighted, and a diffusion-weighted (b0, b1000) sequence. The Peritoneal Cancer Index (PCI) was determined on DW-MR images (MRI-PCI) by two readers, independently, and was compared to the PCI determined during surgery (S-PCI). The inter-observer agreement between the two radiologists was evaluated. In addition, receiver operating characteristics curves were calculated for predicting complete cytoreduction with the S-PCI and MRI-PCI. RESULTS: Staging with DW-MRI showed a correlation to surgical staging with an intraclass correlation coefficient (ICC) 0.86 and 0.85 for reader 1 and 2, respectively. Inter-observer agreement was excellent with an ICC of 0.90 (95% CI: 0.64-0.96). The MRI-PCI scores of reader 1 (AUC = 0.96), reader 2 (AUC = 0.98), and the S-PCI (AUC = 0.92) showed similar predictive values for complete cytoreduction. CONCLUSION: DW-MRI is accurate in predicting the S-PCI and can be helpful to predict whether a complete resection in ovarian cancer patients is feasible.

Diffusion-weighted MRI assessment of the peritoneal cancer index before cytoreductive surgery.

BACKGROUND: Patients with limited peritoneal metastases from colorectal cancer may be candidates for an aggressive surgical approach including cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). Selection is based on surgical inspection during laparoscopy or laparotomy. The aim of this study was to investigate whether diffusion-weighted MRI (DW-MRI) can be used to select patients for CRS-HIPEC. METHODS: This was a prospective study at a tertiary referral centre. Patients with confirmed or suspected colorectal peritoneal metastases scheduled for exploratory laparotomy or laparoscopy were eligible. Two radiologists assessed the peritoneal cancer index (PCI) on CT (CT-PCI) and DW-MRI (MRI-PCI). The reference standard was PCI at surgery. Radiologists were blinded to the surgical PCI and to each other's findings. The main outcome was the accuracy of DW-MRI in predicting whether patients had resectable disease (PCI less than 21) or not. RESULTS: Fifty-six patients were included in the study, of whom 49 could be evaluated. The mean(s.d.) PCI at surgery was 11·27(7·53). The mean MRI-PCI was 10·18(7·07) for reader 1 and 8·59(7·08) for reader 2. Readers 1 and 2 correctly staged 47 of 49 and 44 of 49 patients respectively (accuracy 96 and 90 per cent). Both readers detected all patients with resectable disease with a PCI below 21 at surgery (sensitivity 100 per cent). No patient was overstaged. The intraclass correlation (ICC) between readers was excellent (ICC 0·91, 95 per cent c.i. 0·77 to 0·96). MRI-PCI had a stronger correlation with surgical PCI (ICC 0·83-0·88) than did CT-PCI (ICC 0·39-0·44). CONCLUSION: DW-MRI is a promising non-invasive tool to guide treatment selection in patients with peritoneal metastases from colorectal cancer.

Dual-energy CT can detect malignant lymph nodes in rectal cancer.

BACKGROUND: There is a need for an accurate and operator independent method to assess the lymph node status to provide the most optimal personalized treatment for rectal cancer patients. This study evaluates whether Dual Energy Computed Tomography (DECT) could contribute to the preoperative lymph node assessment, and compared it to Magnetic Resonance Imaging (MRI). The objective of this prospective observational feasibility study was to determine the clinical value of the DECT for the detection of metastases in the pelvic lymph nodes of rectal cancer patients and compare the findings to MRI and histopathology. MATERIALS AND METHODS: The patients were referred to total mesorectal excision (TME) without any neoadjuvant oncological treatment. After surgery the rectum specimen was scanned, and lymph nodes were matched to the pathology report. Fifty-four histology proven rectal cancer patients received a pelvic DECT scan and a standard MRI. The Dual Energy CT quantitative parameters were analyzed: Water and Iodine concentration, Dual-Energy Ratio, Dual Energy Index, and Effective Z value, for the benign and malignant lymph node differentiation. RESULTS: DECT scanning showed statistical difference between malignant and benign lymph nodes in the measurements of iodine concentration, Dual-Energy Ratio, Dual Energy Index, and Effective Z value. Dual energy CT classified 42% of the cases correctly according to N-stage compared to 40% for MRI. CONCLUSION: This study showed statistical difference in several quantitative parameters between benign and malignant lymph nodes. There were no difference in the accuracy of lymph node staging between DECT and MRI.

Measurements of nanoresonator-qubit interactions in a hybrid quantum electromechanical system.

Experiments to probe the basic quantum properties of motional degrees of freedom of mechanical systems have developed rapidly over the last decade. One promising approach is to use hybrid electromechanical systems incorporating superconducting qubits and microwave circuitry. However, a critical challenge facing the development of these systems is to achieve strong coupling between mechanics and qubits while simultaneously reducing coupling of both the qubit and mechanical mode to the environment. Here we report measurements of a qubit-coupled mechanical resonator system consisting of an ultra-high-frequency nanoresonator and a long coherence-time superconducting transmon qubit, embedded in a superconducting coplanar waveguide cavity. It is demonstrated that the nanoresonator and transmon have commensurate energies and transmon coherence times are one order of magnitude larger than for all previously reported qubit-coupled nanoresonators. Moreover, we show that numerical simulations of this new hybrid quantum system are in good agreement with spectroscopic measurements and suggest that the nanoresonator in our device resides at low thermal occupation number, near its ground state, acting as a dissipative bath seen by the qubit. We also outline how this system could soon be developed as a platform for implementing more advanced experiments with direct relevance to quantum information processing and quantum thermodynamics, including the study of nanoresonator quantum noise properties, reservoir engineering, and nanomechanical quantum state generation and detection.