Metastatic Colorectal Cancer Treated with Combined Liver Resection, Cytoreductive Surgery, and Hyperthermic Intraperitoneal Chemotherapy (HIPEC): Predictive Factors for Early Recurrence.

BACKGROUND: Selection of colorectal cancer patients with concomitant peritoneal (PM) and liver metastases (LM) for radical treatment with cytoreductive surgery (CRS), including liver resection and hyperthermic intraperitoneal chemotherapy (HIPEC), needs improvement. This retrospective, monocentric study was designed to evaluate the predictive factors for early recurrence, disease-free survival (DFS), and overall survival (OS) in such patients treated in a referral center. METHODS: Consecutive colorectal cancer patients with concomitant LM and PM treated with curative intent with perioperative systemic chemotherapy, simultaneous complete CRS, liver resection, and HIPEC in 2011-2022 were included. Clinical, radiological (before and after preoperative chemotherapy), surgical, and pathological data were investigated, along with long-term oncologic outcomes. A multivariate analysis was performed to identify predictive factors associated with early recurrence (diagnosed <6 months after surgery), DFS, and OS. RESULTS: Of more than 61 patients included, 31 (47.1%) had pT4 and 27 (40.9%) had pN2 primary tumors. Before preoperative chemotherapy, the median number of LM was 2 (1-4). The median surgical PCI (peritoneal carcinomatosis index) was 3 (5-8.5). The median DFS and OS were 8.15 (95% confidence interval [CI] 5.5-10.1) and 34.1 months (95% CI 28.1-53.5), respectively. In multivariate analysis, pT4 (odds ratio [OR] = 4.14 [1.2-16.78], p = 0.032]) and pN2 (OR = 3.7 [1.08-13.86], p = 0.042) status were independently associated with an early recurrence, whereas retroperitoneal lymph node metastasis (hazard ratio [HR] = 39 [8.67-175.44], p < 0.001) was independently associated with poor OS. CONCLUSIONS: In colorectal cancer patients with concomitant PM and LM, an advanced primary tumor (pT4 and/or pN2) was associated with a higher risk of early recurrence following a radical multimodal treatment, whereas RLN metastases was strongly detrimental for OS.

Prediction of post-hepatectomy liver failure by preoperative gadoxetate disodium-enhanced magnetic resonance imaging.

BACKGROUND: Approximately 15% of patients experience post-hepatectomy liver failure after major hepatectomy. Poor hepatocyte uptake of gadoxetate disodium, a magnetic resonance imaging contrast agent, may be a predictor of post-hepatectomy liver failure. METHODS: A retrospective cohort study of patients undergoing major hepatectomy (≥3 segments) with a preoperative gadoxetate disodium-enhanced magnetic resonance imaging was conducted. The liver signal intensity (standardized to the spleen) and the functional liver remnant was calculated to determine if this can predict post-hepatectomy liver failure after major hepatectomy. RESULTS: In 134 patients, low signal intensity of the remnant liver standardized by signal intensity of the spleen in post-contrast images was associated with post-hepatectomy liver failure in multiple logistic regression analysis (Odds Ratio 0.112; 95% CI 0.023-0.551). In a subgroup of 33 patients with lower quartile of functional liver remnant, area under the curve analysis demonstrated a diagnostic accuracy of functional liver remnant to predict post-hepatectomy liver failure of 0.857 with a cut-off value for functional liver remnant of 1.4985 with 80.0% sensitivity and 89.3% specificity. CONCLUSION: Functional liver remnant determined by gadoxetate disodium-enhanced magnetic resonance imaging is a predictor of post-hepatectomy liver failure which may help identify patients for resection, reducing morbidity and mortality.

Polycystic liver: automatic segmentation using deep learning on CT is faster and as accurate compared to manual segmentation.

OBJECTIVE: This study aimed to develop and investigate the performance of a deep learning model based on a convolutional neural network (CNN) for the automatic segmentation of polycystic livers at CT imaging. METHOD: This retrospective study used CT images of polycystic livers. To develop the CNN, supervised training and validation phases were performed using 190 CT series. To assess performance, the test phase was performed using 41 CT series. Manual segmentation by an expert radiologist (Rad1a) served as reference for all comparisons. Intra-observer variability was determined by the same reader after 12 weeks (Rad1b), and inter-observer variability by a second reader (Rad2). The Dice similarity coefficient (DSC) evaluated overlap between segmentations. CNN performance was assessed using the concordance correlation coefficient (CCC) and the two-by-two difference between the CCCs; their confidence interval was estimated with bootstrap and Bland-Altman analyses. Liver segmentation time was automatically recorded for each method. RESULTS: A total of 231 series from 129 CT examinations on 88 consecutive patients were collected. For the CNN, the DSC was 0.95 ± 0.03 and volume analyses yielded a CCC of 0.995 compared with reference. No statistical difference was observed in the CCC between CNN automatic segmentation and manual segmentations performed to evaluate inter-observer and intra-observer variability. While manual segmentation required 22.4 ± 10.4 min, central and graphics processing units took an average of 5.0 ± 2.1 s and 2.0 ± 1.4 s, respectively. CONCLUSION: Compared with manual segmentation, automated segmentation of polycystic livers using a deep learning method achieved much faster segmentation with similar performance. KEY POINTS: • Automatic volumetry of polycystic livers using artificial intelligence method allows much faster segmentation than expert manual segmentation with similar performance. • No statistical difference was observed between automatic segmentation, inter-observer variability, or intra-observer variability.

Unifocal versus Multiple Ileal Neuroendocrine Tumors Location: An Embryological Origin.

INTRODUCTION: Small-intestinal neuroendocrine tumors (SI-NET) are situated preferentially within the ileum. The aim was to describe a potential difference in location between unifocal and multiple ileal-NET. PATIENTS AND METHODS: Between December 2010 and December 2019, all consecutive patients who underwent resection in our European Neuroendocrine Tumor Society Center of Excellence, of at least 1 non-duodenal SI-NET, were retrospectively included. The main objective was to prove that multiple ileal-NET were mostly located on the left side of the superior mesenteric artery (SMA) axis (defined as 40 cm from the ileocecal valve), and unifocal ones on the right side. RESULTS: Ninety-four patients were included, 6 with unifocal jejunal-NET located 35 cm (range, 10-60) from the duodenojejunal angle (DJA), 44 (47%) with unifocal ileal-NET and 44 (47%) with multiple ileal-NET. The median number of tumors in multiple ileal-NET was 7 (range, 2-95), within a median small bowel segment of 105 cm (10-240). The median length between the proximal tumor and the DJA was 428 cm (300-635) and 540 cm (350-725) for the distal one; 40 (91%) of them were located on the left side of the SMA axis. In contrast, unifocal ileal-NET were located at a median distance of 577 cm (305-820) from the DJA (p < 0.001, compared to multiple ileal-NET); 30 (68%) of them were on the right side of the SMA axis (p < 0.001). CONCLUSION: Multiple ileal-NET are mostly located on the left side of the SMA axis. Further studies are warranted to explore the embryological origin of unifocal versus multiple ileal-NET.

Rectal endometriosis: predictive MRI signs for segmental bowel resection.

OBJECTIVE: To retrospectively determine the accuracy of MRI rectal and pararectal signs in predicting the necessity for segmental resection in the case of lesions located in the rectum. METHODS: MR images of consecutive patients treated for rectal endometriosis over a 5-year period were reviewed in consensus by two blinded readers. A systematic analysis of 7 rectal (lesion length, transverse axis, thickness and circumference, and presence of a convex base, submucosal oedema and hyperintense cystic areas) and 4 pararectal (posterior vaginal fornix, parametrial, ureteral and sacro-recto-genital septum involvements) signs was performed for each lesion. MRI results were compared to the surgical procedure performed (shaving versus segmental resection). RESULTS: Among 61 patients studied, 32 received a segmental resection and 29, a shaving. Receiver operating characteristic curve analysis allowed determining cut-off values for length (≥ 32 mm), transverse axis (≥ 22 mm), thickness (≥ 14 mm) and circumference (≥ 3/8 radii). The 7 rectal signs, and only the sacro-recto-genital septum pararectal sign, were significantly associated with segmental resection in univariate analysis, nodular thickness ≥ 14 mm and circumference ≥ 3/8 radii being the most predictive signs (odds ratio 94.5 and 60.4, respectively). These 2 signs remained positively associated with segmental resection in multivariate analysis and, when combined, were predictive of segmental resection with an accuracy of 90.2%. CONCLUSION: Assessing MRI rectal and pararectal signs may accurately predict the need for segmental resection versus a more conservative approach such as shaving for rectal lesion management. KEY POINTS: • MRI analysis of rectal endometriosis, taking into account rectal and pararectal signs, may assist surgeons in the decision-making process, in counselling patients regarding the surgical procedure and in adequately allocating resources. • Among rectal signs, nodular thickness ≥ 14 mm and a circumference ≥ 38% were the most predictive signs of segmental resection. • Among pararectal signs, only the sacro-recto-genital septum involvement was significantly associated with segmental resection.

Chest CT for rapid triage of patients in multiple emergency departments during COVID-19 epidemic: experience report from a large French university hospital.

OBJECTIVES: To assess the diagnostic performances of chest CT for triage of patients in multiple emergency departments during COVID-19 epidemic, in comparison with reverse transcription polymerase chain reaction (RT-PCR) test. METHOD: From March 3 to April 4, 2020, 694 consecutive patients from three emergency departments of a large university hospital, for which a hospitalization was planned whatever the reasons, i.e., COVID- or non-COVID-related, underwent a chest CT and one or several RT-PCR tests. Chest CTs were rated as "Surely COVID+," "Possible COVID+," or "COVID-" by experienced radiologists. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using the final RT-PCR test as standard of reference. The delays for CT reports and RT-PCR results were recorded and compared. RESULTS: Among the 694 patients, 287 were positive on the final RT-PCR exam. Concerning the 694 chest CT, 308 were rated as "Surely COVID+", 34 as "Possible COVID+," and 352 as "COVID-." When considering only the "Surely COVID+" CT as positive, accuracy, sensitivity, specificity, PPV, and NPV reached 88.9%, 90.2%, 88%, 84.1%, and 92.7%, respectively, with respect to final RT-PCR test. The mean delay for CT reports was three times shorter than for RT-PCR results (187 ± 148 min versus 573 ± 327 min, p < 0.0001). CONCLUSION: During COVID-19 epidemic phase, chest CT is a rapid and most probably an adequately reliable tool to refer patients requiring hospitalization to the COVID+ or COVID- hospital units, when response times for virological tests are too long. KEY POINTS: • In a large university hospital in Lyon, France, the accuracy, sensitivity, specificity, PPV, and NPV of chest CT for COVID-19 reached 88.9%, 90.2%, 88%, 84.1%, and 92.7%, respectively, using RT-PCR as standard of reference. • The mean delay for CT reports was three times shorter than for RT-PCR results (187 ± 148 min versus 573 ± 327 min, p < 0.0001). • Due to high accuracy of chest CT for COVID-19 and shorter time for CT reports than RT-PCR results, chest CT can be used to orient patients suspected to be positive towards the COVID+ unit to decrease congestion in the emergency departments.

Characterization of Focal Liver Masses: A Multicenter Comparison of Contrast-Enhanced Ultrasound, Computed Tomography, and Magnetic Resonance Imaging.

OBJECTIVES: To demonstrate the usefulness of contrast-enhanced ultrasound (CEUS) for the evaluation of focal liver masses via a direct comparison to standard ultrasound and computed tomography/magnetic resonance imaging (CT/MRI). METHODS: A cohort of 214 patients with previously undiagnosed focal liver masses were included from 5 different centers. Each patient was imaged using CEUS and CT and/or MRI. Anonymized and randomized images were interpreted by 4 separate blind readers from 3 of the participating centers (2 readers for CEUS and 2 readers for CT/MRI). Readers were blinded to patient demographics and past medical history. Readers were asked to decide if the lesion was benign or malignant, provide a final diagnosis for the lesion, and provide a confidence interval. Results were compared to truth standard from pathology or expert consensus. RESULTS: In determination of malignancy, CEUS had a sensitivity of 95%, specificity of 82%, PPV of 82%, NPV of 95%, statistically better than standard ultrasound (sensitivity 82%, specificity 56%, PPV 60%, NPV 78%) with P < .01 and not statistically different from CT (sensitivity 90%, specificity 73% PPV 81%, NPV 86%) or MRI (sensitivity 85%, specificity 79%, PPV 68%, NPV 91%) with P ≥ .01. In assigning a final diagnosis, CEUS had an accuracy of 78% statistically better than standard ultrasound (46%) with P < .01 and not statistically different from CT (68%) or MRI (71%) with P > .01. CONCLUSIONS: In the evaluation of focal liver lesions, both for determination of malignancy and in accuracy of final diagnosis, CEUS performs better than standard ultrasound and at least equivalent to both CT and MRI.

Using decision curve analysis to benchmark performance of a magnetic resonance imaging-based deep learning model for prostate cancer risk assessment.

OBJECTIVES: To benchmark the performance of a calibrated 3D convolutional neural network (CNN) applied to multiparametric MRI (mpMRI) for risk assessment of clinically significant prostate cancer (csPCa) using decision curve analysis (DCA). METHODS: We retrospectively analyzed 499 patients who had positive mpMRI (PI-RADSv2 ≥ 3) and MRI-targeted biopsy. The training cohort comprised 449 men, including a calibration set of 50 men. Biopsy decision strategies included using risk estimates from the CNN (original and calibrated), to perform biopsy in men with PI-RADSv2 ≥ 4 only, or additionally in men with PI-RADSv2 3 and PSA density (PSAd) ≥ 0.15 ng/ml/ml. Discrimination, calibration and clinical usefulness in the unseen test cohort (n = 50) were assessed using C-statistic, calibration plots and DCA, respectively. RESULTS: The calibrated CNN achieved moderate calibration (Hosmer-Lemeshow calibration test, p = 0.41) and good discrimination (C = 0.85). DCA revealed consistently higher net benefit and net reduction in biopsies for the calibrated CNN compared with the original CNN, PI-RADSv2 ≥ 4 and the combined strategy of PI-RADSv2 and PSAd. Original CNN predictions were severely miscalibrated (p < 0.0001) resulting in net harm compared with a 'biopsy all' patients strategy. At-risk thresholds ≥ 10% using the calibrated CNN and the combined strategy reduced the number of biopsies by an estimated 201 and 55 men, respectively, per 1000 men at risk, without missing csPCa, while original CNN and PI-RADSv2 ≥ 4 could not achieve a net reduction in biopsies. CONCLUSIONS: DCA revealed that our calibrated 3D-CNN resulted in fewer unnecessary biopsies compared with using PI-RADSv2 alone or in combination with PSAd. CNN calibration is important in achieving clinical utility. KEY POINTS: • A 3D deep learning model applied to multiparametric MRI may help to prevent unnecessary prostate biopsies in patients eligible for MRI-targeted biopsy. • Owing to miscalibration, original risk estimates by the deep learning model require prior calibration to enable clinical utility. • Decision curve analysis confirmed a net benefit of using our calibrated deep learning model for biopsy decisions compared with alternative strategies, including PI-RADSv2 alone and in combination with prostate-specific antigen density.

Right Colectomy with Absorbable Mesh Repair as a Salvage Solution for the Management of Giant Incisional Hernia with Loss of Domain: Results of a Bicentric Study.

BACKGROUND: Incisional hernia (IH) may occur in 20% of patients after laparotomy. The hernia sac volume may be of significance, with reintegration of visceral contents potentially leading to repair failure or abdominal compartment syndrome. The present study aimed to evaluate a two-step surgical strategy comprising right colectomy for hernia reduction with synchronous absorbable mesh repair followed by definitive non-absorbable mesh repair in recurrence. METHODS: Patients operated between 2012 and 2017 at two university centers were retrospectively included. Volumetric evaluation of the IH was performed by CT imaging. RESULTS: Eleven patients were included. The mean BMI was 43 kg/m2 (23-52 kg/m2). Progressive preoperative pneumoperitoneum was performed in 82% of patients, with complications in 22%. The mean volumetric ratio of the volume of the hernia to the volume of the abdominal cavity was 70% (48-100%). The first parietal repair was performed using an synthetic absorbable mesh (36%), a biologic mesh (27%), or a slowly absorbable mesh (36%). No patients died as a result of the procedure. Seven (64%) patients developed grade III-IV complications, including one case of an anastomotic fistula. Recurrence occurred in eight (73%) patients after the first repair. Of these, four (50%) patients were reoperated using a non-absorbable mesh, leading to solid repair in 75% of cases. After 27 ± 18 months of follow-up, the residual IH rate was 46%. CONCLUSIONS: Right colectomy for volume reduction in IH with loss of domain potentially represents an appropriate salvage option, supporting bowel reintegration and temporary hernia repair with absorbable material.

Value of Increasing Biopsy Cores per Target with Cognitive MRI-targeted Transrectal US Prostate Biopsy.

Purpose To determine the increase in clinically significant cancer detection in the prostate with increasing number of core samples obtained by using cognitive MRI-targeted transrectal US biopsy. Materials and Methods This retrospective cross-sectional study included 330 consecutive patients (mean age, 64.3 years; range, 42-84 years) who underwent multiparametric prostate MRI from March 2012 to July 2017 and had an index lesion that subsequently underwent cognitive MRI-targeted biopsy using transrectal US with at least five core samples (which were sequentially labeled) per lesion. The detection rate of clinically significant cancer was calculated on sequential biopsy cores, comparing the first core alone versus three cores versus five cores per target. Clinically significant cancer was defined as International Society of Urological Pathology Grade Group 2 or higher. Results Increasing the number of biopsy core samples from one to three per target and from three to five per target increased the detection rate of clinically significant cancer by 6.4% (21 of 330) and 2.4% (eight of 330), respectively. The target yield for clinically significant cancer was 26% (87 of 330), 33% (108 of 330), and 35% (116 of 330) for one, three, and five cores, respectively. Subgroup analysis showed no significant difference in upgrade rates as a function of multiparametric MRI lesion size (P = .53-.59) or location (P = .28-.89). Conclusion More clinically significant prostate cancers are detected when increasing the number of core biopsy samples per index lesion from one to three and from three to five (6.4% and 2.4%, respectively) when performing cognitive MRI-targeted transrectal US biopsy. © RSNA, 2019 See also the editorial by Oto in this issue.

Delayed tumour enhancement on gadoxetate-enhanced MRI is associated with overall survival in patients with colorectal liver metastases.

OBJECTIVES: To determine whether tumour enhancement on preoperative delayed-phase gadoxetate-enhanced MRI can predict long-term survival in patients with colorectal liver metastases (CRCLM) post-hepatectomy. MATERIALS AND METHODS: Sixty-five patients who received a preoperative gadoxetate-enhanced MRI prior to liver resection for CRCLM from January 1, 2010, to December 31, 2012, were included in this retrospective study. Target tumour enhancement (TuEn) was calculated as the mean percentage increase in SNR from precontrast to 10-min or 20-min delayed phase for up to two target lesions. Per-patient TuEn was stratified into weak and strong enhancement based on the cut-off determined by the Youden Index for 3-year survival. Kaplan-Meier and Cox regression analyses were used to determine whether tumour enhancement could predict overall survival independent of potential confounders (clinical risk score). RESULTS: The proportion surviving at 3 years was 85.1% in patients with strong TuEn at 10 min vs. 56.5% in those with weak TuEn at 10 min (p = 0.001). The proportion surviving at 3 years was 79.4% in patients with strong TuEn at 20 min vs. 58.7% in those with weak TuEn at 20 min (p = 0.011). After adjusting for potential confounders, the hazard ratio of death was 0.24 (p = 0.009) in patients who had weak TuEn at 10 min and 0.32 (p = 0.018) in patients who had weak TuEn at 20 min. CONCLUSIONS: Strong delayed tumour enhancement seen on gadoxetate-enhanced MRI is associated with overall survival in patients with CRCLM post-hepatectomy and may be useful for preoperative risk stratification. KEY POINTS: • Delayed tumour enhancement of colorectal liver metastases on gadoxetate-enhanced MRI is associated with survival post-hepatectomy • Delayed tumour enhancement of colorectal liver metastases on gadoxetate-enhanced MRI can be measured at both 10 min and 20 min post-contrast injection.

Late gadolinium MRI enhancement of colorectal liver metastases is associated with overall survival among nonsurgical patients.

PURPOSE: To determine if late gadolinium MRI enhancement of colorectal liver metastases (CRCLM) is associated with overall survival among nonsurgical patients. MATERIALS AND METHODS: This retrospective study was approved by the institutional research ethics board. Late gadolinium enhancement was measured using target tumour enhancement (TTE) in all nonsurgical patients with CRCLM who received a 10-min delayed phase gadobutrol-enhanced liver MRI between March 1, 2006, and August 31, 2014. A total of 122 patients met inclusion/exclusion criteria. Patients were dichotomized into strong and weak TTE. Kaplan-Meier and Cox regression statistics were used to determine whether TTE was associated with overall survival. Noncontributory potential confounding variables (age, sex, number and size of metastases, carcinoembryonic (CEA) level, and presence of extrahepatic disease) were excluded from the final Cox regression model using the backward Wald elimination. Subgroup Kaplan-Meier survival analyses were performed on patients who were chemotherapy-naïve and chemotherapy-treated at the time of MRI. RESULTS: Strong TTE had increased survival compared with those with weak TTE on Kaplan-Meier analysis (2-year survival: 69.8% vs. 43.5%, p = 0.002). Among 96 patients where data was available for multivariable analysis, weak TTE was associated with death (adjusted hazard ratio 0.25, 95% CI 0.11-0.59, p = 0.002), after adjusting for CEA level. Other potential confounders were noncontributory. Subgroup analyses demonstrated that strong TTE had increased survival compared with those with weak TTE in both the chemotherapy-naïve (p = 0.047) and chemotherapy-treated (p = 0.008) groups. CONCLUSION: Strong late gadolinium MRI enhancement of CRCLM is associated with overall survival among nonsurgical patients. KEY POINTS: • MRI enhancement of colorectal liver metastases is associated with overall survival in nonsurgical patients. • MRI enhancement of colorectal liver metastases is associated with overall survival in both chemotherapy-naïve and chemotherapy-treated subgroups.

Selection of Patients With Rectal Cancer for Preoperative Chemoradiotherapy: Are T Category and Nodal Status All That Matters?

BACKGROUND: Although the accuracy of preoperative MRI staging has been established on follow-up histopathologic examination, the reproducibility of MRI staging has been evaluated in studies with expert radiologists reading a large sample of MRI images and therefore is not generalizable to the real-world setting. OBJECTIVE: The purpose of this study was to evaluate the interrater reliability of MRI for distance to the mesorectal fascia, T category, mesorectal lymph node status, and extramural depth of invasion for preoperative staging of primary rectal cancer. DESIGN: This was a prospective, cross-sectional survey. SETTINGS: The study was conducted in Ontario, Canada. PARTICIPANTS: Participants included GI radiologists. INTERVENTIONS: Participants read 5 preselected staging MRIs using a synoptic report and participated in an educational Webinar. MAIN OUTCOME MEASURES: Distance to the mesorectal fascia, T category, extramural depth of invasion, and mesorectal lymph node status for each MRI were abstracted. Data were analyzed in aggregate using percentage of agreement, Fleiss κ, and interclass correlation coefficients to assess interrater reliability. RESULTS: Reliability was highest for distance to the mesorectal fascia with an intraclass correlation of 0.58 (95% CI, 0.27-0.80). Kappa scores for T category, mesorectal lymph node status, and extramural depth of invasion were 0.38 (95% CI, 0.23-0.46), 0.41 (95% CI, 0.32-0.49), and 0.37 (95% CI, 0.16-0.82). There was no difference when radiologists were stratified by experience or volume. LIMITATIONS: Scores may have been affected by MRI selection, because they were chosen to demonstrate diagnostic challenges for the Webinar and did not reflect a representative sample. CONCLUSIONS: Interrater reliability was highest for distance to mesorectal fascia, and therefore, it may be a more reliable criterion than T category, extramural depth of invasion, or mesorectal lymph node status. Combined with the fact that an uninvolved mesorectal fascia is more consistent with the overall goal of rectal cancer surgery, it should be considered as an important MRI criterion for preoperative treatment decision making in the real-world setting. See Video Abstract at http://links.lww.com/DCR/A763.

Late Gadolinium Hyperintensity of Suspected Colorectal Liver Metastases on Gadofosveset-Enhanced Magnetic Resonance Imaging: A Predictor of Benignity and a Potential Problem-Solving Tool.

PURPOSE: Late gadolinium hyperintensity (LGH) is sometimes seen in colorectal liver metastasis (CRLM) and represents a significant diagnostic pitfall due to overlap with LGH in benign hemangiomas; therefore, the objective of this study was to determine the prevalence of LGH and the ability of LGH to differentiate between CRLM and benign lesions with intravascular (gadofosveset) vs extracellular contrast agents (gadobutrol). METHODS: Patients with known colorectal cancer and suspected liver lesions were prospectively recruited into this institutional review board-approved, single institution study and received magnetic resonance imaging of the liver with gadofosveset and gadobutrol. The prevalence of LGH for CRLMs and solid benign lesions was determined. Receiver operating characteristics curves were determined for the presence of LGH as a predictor of benignity. The utility of LGH to differentiate between CRLM and solid benign lesions using gadofosveset vs gadobutrol was compared using the generalized estimating equation. RESULTS: Twenty-five patients with 131 solid focal liver lesions were recruited. The prevalence of LGH of CRLMs was 11.2% (95% confidence interval [CI]: 0.5%-21.8%) with gadofosveset vs 63.7% (95% CI: 45.7%-81.7%) with gadobutrol. The area under the receiver operating characteristic curve for the presence of LGH as a predictor of benignity was 0.86 using gadofosveset vs 0.75 using gadobutrol. Both LGH (P = .003) and the interaction of contrast agent and LGH (P = .003) statistically significantly differentiated CRLM from benign lesions. CONCLUSION: LGH is more common with extracellular than with intravascular contrast agents and is statistically significantly associated with benign lesions rather than metastases.

Reducing repeat imaging in hepato-pancreatico-biliary surgical cancer care through shared diagnostic imaging repositories.

BACKGROUND: With regionalization of care, patients often undergo treatment in institutions other than where the initial investigation is conducted. This study assessed the impact of a shared diagnostic imaging repository (SDIR) on processes of care and outcomes in hepato-pancreatico-biliary (HPB) cancer surgery. METHODS: Provincial administrative datasets were linked to study HPB cancer patients operated at a regional cancer centre (2003-2014). SDIR and non-SDIR groups were based on where initial imaging (CT or MRI) was conducted. Outcomes were repeat imaging before surgery and wait times for surgery from initial imaging and surgical consultation. RESULTS: Of 839 patients, 474 were from SDIR institutions. Fewer SDIR patients underwent any repeat imaging (55.9% vs. 75.3%; p < 0.01) and repeat imaging with same modality and protocol (24.7% vs. 43.0%; p < 0.01). Median wait time to surgery from initial imaging (64 Vs. 79 days; p < 0.01) and surgical consultation (39 Vs. 45 days; p = 0.046) was shorter with SDIR. SDIR patients had lower adjusted odds of any repeat imaging (OR 0.20 [0.14-0.30]), and repeat imaging with same modality and protocol (OR 0.58 [0.41-0.80]). CONCLUSION: Radiology sharing with SDIR reduced repeat imaging for HPB cancer surgery, including potentially redundant repeat imaging with same protocol, and shortened wait time to surgical care.

Late gadolinium enhancement of colorectal liver metastases post-chemotherapy is associated with tumour fibrosis and overall survival post-hepatectomy.

PURPOSE: To determine whether late gadolinium MRI enhancement of colorectal liver metastases (CRCLM) post-chemotherapy is associated with tumour fibrosis and survival post-hepatectomy. MATERIALS AND METHODS: The institutional review board approved this retrospective cohort study and waived the requirement for informed consent. A cohort of 121 surgical patients who received preoperative MRI after chemotherapy between 2006-2012 was included in this study. Target tumour enhancement (TTE), defined as the mean contrast-to-noise ratio of up to two target lesions on late-phase gadobutrol-enhanced MRI, was determined by two independent raters. The average TTE was correlated with tumour fibrosis on post-hepatectomy specimens using Spearman correlation and with survival post-hepatectomy using Kaplan-Meier and Cox regression. Inter-rater reliability was determined using relative intra-class correlation coefficients. RESULTS: In the surgical cohort (mean age: 63.0 years; male: 58%), TTE was associated with tumour fibrosis (r = 0.43, p < 0.001). Strong TTE was associated with improved survival compared to weak TTE (3-year survival: 88.4% vs. 58.8%, p = 0.003) with a hazard ratio of 0.32 (95% CI: 0.14-0.75, p = 0.008), after taking into account known prognostic variables. Inter-rater reliability was very good with a relative intraclass correlation of 0.84 (95% CI: 0.77-0.89). CONCLUSION: Late gadolinium MRI enhancement of CRCLM post-chemotherapy is associated with tumour fibrosis and survival. KEY POINTS: • MRI enhancement of colorectal liver metastases is associated with survival post-hepatectomy • MRI enhancement of chemotherapy-treated colorectal liver metastases correlates with tumour fibrosis • Measuring late MRI enhancement using target tumour enhancement is reliable.

The prognostic and predictive value of vascular response parameters measured by dynamic contrast-enhanced-CT, -MRI and -US in patients with metastatic renal cell carcinoma receiving sunitinib.

OBJECTIVES: To identify dynamic contrast-enhanced (DCE) imaging parameters from MRI, CT and US that are prognostic and predictive in patients with metastatic renal cell cancer (mRCC) receiving sunitinib. METHODS: Thirty-four patients were monitored by DCE imaging on day 0 and 14 of the first course of sunitinib treatment. Additional scans were performed with DCE-US only (day 7 or 28 and 2 weeks after the treatment break). Perfusion parameters that demonstrated a significant correlation (Spearman p < 0.05) with progression-free survival (PFS) and overall survival (OS) were investigated using Cox proportional hazard models/ratios (HR) and Kaplan-Meier survival analysis. RESULTS: A higher baseline and day 14 value for Ktrans (DCE-MRI) and a lower pre-treatment vascular heterogeneity (DCE-US) were significantly associated with a longer PFS (HR, 0.62, 0.37 and 5.5, respectively). A larger per cent decrease in blood volume on day 14 (DCE-US) predicted a longer OS (HR, 1.45). We did not find significant correlations between any of the DCE-CT parameters and PFS/OS, unless a cut-off analysis was used. CONCLUSIONS: DCE-MRI, -CT and ultrasound produce complementary parameters that reflect the prognosis of patients receiving sunitinib for mRCC. Blood volume measured by DCE-US was the only parameter whose change during early anti-angiogenic therapy predicted for OS and PFS. KEY POINTS: • DCE-CT, -MRI and ultrasound are complementary modalities for monitoring anti-angiogenic therapy. • The change in blood volume measured by DCE-US was predictive of OS/PFS. • Baseline vascular heterogeneity by DCE-US has the strongest prognostic value for PFS.