Superiority of Step-up Approach vs Open Necrosectomy in Long-term Follow-up of Patients With Necrotizing Pancreatitis.

BACKGROUND & AIMS: In a 2010 randomized trial (the PANTER trial), a surgical step-up approach for infected necrotizing pancreatitis was found to reduce the composite endpoint of death or major complications compared with open necrosectomy; 35% of patients were successfully treated with simple catheter drainage only. There is concern, however, that minimally invasive treatment increases the need for reinterventions for residual peripancreatic necrotic collections and other complications during the long term. We therefore performed a long-term follow-up study. METHODS: We reevaluated all the 73 patients (of the 88 patients randomly assigned to groups) who were still alive after the index admission, at a mean 86 months (±11 months) of follow-up. We collected data on all clinical and health care resource utilization endpoints through this follow-up period. The primary endpoint was death or major complications (the same as for the PANTER trial). We also measured exocrine insufficiency, quality of life (using the Short Form-36 and EuroQol 5 dimensions forms), and Izbicki pain scores. RESULTS: From index admission to long-term follow-up, 19 patients (44%) died or had major complications in the step-up group compared with 33 patients (73%) in the open-necrosectomy group (P = .005). Significantly lower proportions of patients in the step-up group had incisional hernias (23% vs 53%; P = .004), pancreatic exocrine insufficiency (29% vs 56%; P = .03), or endocrine insufficiency (40% vs 64%; P = .05). There were no significant differences between groups in proportions of patients requiring additional drainage procedures (11% vs 13%; P = .99) or pancreatic surgery (11% vs 5%; P = .43), or in recurrent acute pancreatitis, chronic pancreatitis, Izbicki pain scores, or medical costs. Quality of life increased during follow-up without a significant difference between groups. CONCLUSIONS: In an analysis of long-term outcomes of trial participants, we found the step-up approach for necrotizing pancreatitis to be superior to open necrosectomy, without increased risk of reinterventions.

Added value of intra-operative ultrasound to determine the resectability of locally advanced pancreatic cancer following FOLFIRINOX chemotherapy (IMAGE): a prospective multicenter study.

BACKGROUND: Determining the resectability of locally advanced pancreatic cancer (LAPC) after FOLFIRINOX chemotherapy is challenging because CT-scans cannot reliably assess vascular involvement. This study evaluates the added value of intra-operative ultrasound (IOUS) in LAPC following FOLFIRINOX induction chemotherapy. METHODS: Prospective multicenter study in patients with LAPC who underwent explorative laparotomy with IOUS after FOLFIRINOX chemotherapy. Resectability was defined according to the National Comprehensive Cancer Network guidelines. IOUS findings were compared with preoperative CT-scans and pathology results. RESULTS: CT-staging in 38 patients with LAPC after FOLFIRINOX chemotherapy defined 22 patients LAPC, 15 borderline resectable and one resectable. IOUS defined 19 patients LAPC, 13 borderline resectable and six resectable. In 12/38 patients, IOUS changed the resectability status including five patients from borderline resectable to resectable and five patients from LAPC to borderline resectable. Two patients were upstaged from borderline resectable to LAPC. Tumor diameters were significantly smaller upon IOUS (31.7 ± 9.5 mm versus 37.1 ± 10.0 mm, p = 0.001) and resectability varied significantly (p = 0.043). Ultimately, 20 patients underwent resection of whom 14 were evaluated as (borderline) resectable on CT-scan, and 17 on IOUS. DISCUSSION: This prospective study demonstrates that IOUS may change the resectability status up to a third of patients with LAPC following FOLFIRINOX chemotherapy.

Diagnostic performance of a CT-based scoring system for diagnosis of anastomotic leakage after esophagectomy: comparison with subjective CT assessment.

OBJECTIVE: To develop a CT-based prediction score for anastomotic leakage after esophagectomy and compare it to subjective CT interpretation. METHODS: Consecutive patients who underwent a CT scan for a clinical suspicion of anastomotic leakage after esophagectomy with cervical anastomosis between 2003 and 2014 were analyzed. The CT scans were systematically re-evaluated by two radiologists for the presence of specific CT findings and presence of an anastomotic leak. Also, the original CT interpretations were acquired. These results were compared to patients with and without a clinical confirmed leak. RESULTS: Out of 122 patients that underwent CT for a clinical suspicion of anastomotic leakage; 54 had a confirmed leak. In multivariable analysis, anastomotic leakage was associated with mediastinal fluid (OR = 3.4), esophagogastric wall discontinuity (OR = 4.9), mediastinal air (OR = 6.6), and a fistula (OR = 7.2). Based on these criteria, a prediction score was developed resulting in an area-under-the-curve (AUC) of 0.86, sensitivity of 80%, and specificity of 84%. The original interpretation and the systematic subjective CT assessment by two radiologists resulted in AUCs of 0.68 and 0.75 with sensitivities of 52% and 69%, and specificities of 84% and 82%, respectively. CONCLUSION: This CT-based score may provide improved diagnostic performance for diagnosis of anastomotic leakage after esophagectomy. KEY POINTS: • A CT-based score provides improved diagnostic performance for diagnosis of anastomotic leakage. • Leakage associations include mediastinal fluid, mediastinal air, wall discontinuity, and fistula. • A scoring system yields superior diagnostic accuracy compared to subjective CT assessment. • Radiologists may suggest presence of anastomotic leakage based on a prediction score.

Liver CT for vascular mapping during radioembolisation workup: comparison of an early and late arterial phase protocol.

OBJECTIVES: To compare right gastric (RGA) and segment 4 artery (A4) origin detection rates during radioembolisation workup between early and late arterial phase liver CT protocols. METHODS: 100 consecutive patients who underwent liver CT between May 2012-January 2015 with early or late arterial phase protocol (n = 50 each, 10- vs. 20-s post-threshold delay) were included. RGA/A4 origin detection rates, assessed by two raters, and contrast-to-noise ratio (CNR) of the hepatic artery relative to the portal vein were compared between the protocols. RESULTS: The first-second rater scored the RGA origin as visible in 58-65 % (specific proportion of agreement 82 %, κ = 0.62); A4 origin in 96-89 % (94 %, κ = 0.54). Thirty-six percent of RGA origins not detectable by DSA were identified on CT. Origin detection rates were not significantly different for early/late arterial phases. Mean CNR was higher in the early arterial phase protocol (1.7 vs. 1.2, p < 0.001). CONCLUSION: A 10-s delay arterial phase CT protocol does not significantly improve detection of small intra- and extrahepatic branches. RGA origin detection requires further optimization, whereas A4/MHA origin detection is adequate, with good inter-rater reproducibility. CT remains important for preprocedural planning, because it may reveal arterial anatomy not discernible on DSA. KEY POINTS: • An early arterial phase does not significantly improve RGA and A4/MHA origin detection. • RGA origin detection (58-65 %) on CT is still suboptimal. • 36 % of RGA origins undetectable on DSA can be identified on CT. • A4/MHA origin detection (89-96 %) on CT is excellent. • Inter-rater reproducibility is good for RGA and A4/MHA origin detection on CT.

Clinical and pathological outcomes after irreversible electroporation of the pancreas using two parallel plate electrodes: a porcine model.

BACKGROUND: Irreversible electroporation (IRE) by inserting needles around the tumor as treatment for locally advanced pancreatic cancer entails several disadvantages, such as incomplete ablation due to field inhomogeneity, technical difficulties in needle placement and a risk of pancreatic fistula development. This experimental study evaluates outcomes of IRE using paddles in a porcine model. METHODS: Six healthy pigs underwent laparotomy and were treated with 2 separate ablations (in head and tail of the pancreas). Follow-up consisted of clinical and laboratory parameters and contrast-enhanced computed tomography (ceCT) imaging. After 2 weeks, pancreatoduodenectomy was performed for histology and the pigs were terminated. RESULTS: All animals survived 14 days. None of the animals developed signs of infection or significant abdominal distention. Serum amylase and lipase peaked at day 1 postoperatively in all pigs, but normalized without signs of pancreatitis. On ceCT-imaging the ablation zone was visible as an ill-defined, hypodense lesion. No abscesses, cysts or ascites were seen. Histology showed a homogenous fibrotic lesion in all pigs. CONCLUSION: IRE ablation of healthy porcine pancreatic tissue using two plate electrodes is feasible and safe and creates a homogeneous fibrotic lesion. IRE-paddles should be tested on pancreatic adenocarcinoma to determine the effect in cancer tissue.

Calcification of arteries supplying the gastric tube: a new risk factor for anastomotic leakage after esophageal surgery.

PURPOSE: To evaluate the association between the amount and location of calcifications of the supplying arteries of the gastric tube, as determined with a vascular calcification scoring system, and the occurrence of anastomotic leakage after esophagectomy with gastric tube reconstruction in patients with esophageal cancer. MATERIALS AND METHODS: Institutional review board approval was obtained, and the informed consent requirement was waived for this retrospective study. Consecutive patients who underwent elective esophagectomy for cancer with gastric tube reconstruction and cervical anastomosis between 2003 and 2012 were identified from a prospective database. Vascular calcification scores were retrospectively assigned by reviewing the routine preoperative computed tomographic (CT) images. In patients with anastomotic leakage, presence and severity of calcifications of the aorta (score of 0-2), celiac axis (score of 0-2), right postceliac arteries (common hepatic, gastroduodenal, and right gastroepiploic arteries; score of 0-1), and left postceliac arteries (splenic and left gastroepiploic arteries, score of 0-1) along with patient- and procedure-related characteristics were compared with those of patients without leakage by using multivariate logistic regression analysis. RESULTS: Of 246 patients, 58 (24%) experienced anastomotic leakage. No significant differences in patient-related factors were found between patients with leakage and those without leakage, with the exception of more chronic use of steroids in the leakage group (7% [four of 58] vs 0% [0 of 188], P = .003). At univariate analysis, leakage was more common in patients with calcification of the aorta (27% [28 of 102] and 35% [13 of 37] vs 16% [17 of 107], P = .029) and the right postceliac arteries (55% [six of 11] vs 22% [52 of 235], P = .013). At multivariate analysis, both minor (odds ratio, 2.00; 95% confidence interval: 1.02, 3.94) and major (odds ratio, 2.87; 95% confidence interval: 1.22, 6.72) aortic calcifications were associated with leakage. Also, an independent association with leakage was found for calcifications of the right postceliac arteries (odds ratio, 4.22; 95% confidence interval: 1.24, 14.4). CONCLUSION: Atherosclerotic calcification of the aorta and right postceliac arteries that supply the gastric tube is an independent risk factor for anastomotic leakage after esophagectomy.

Arterial and portal venous liver perfusion using selective spin labelling MRI.

PURPOSE: To investigate the feasibility of selective arterial and portal venous liver perfusion imaging with spin labelling (SL) MRI, allowing separate labelling of each blood supply. METHODS: The portal venous perfusion was assessed with a pulsed EPISTAR technique and the arterial perfusion with a pseudo-continuous sequence. To explore precision and reproducibility, portal venous and arterial perfusion were separately quantified in 12 healthy volunteers pre- and postprandially (before and after meal intake). In a subgroup of 6 volunteers, the accuracy of the absolute portal perfusion and its relative postprandial change were compared with MRI flow measurements of the portal vein. RESULTS: The portal venous perfusion significantly increased from 63 ± 22 ml/100g/min preprandially to 132 ± 42 ml/100g/min postprandially. The arterial perfusion was lower with 35 ± 22 preprandially and 22 ± 30 ml/100g/min postprandially. The pre- and postprandial portal perfusion using SL correlated well with flow-based perfusion (r(2) = 0.71). Moreover, postprandial perfusion change correlated well between SL- and flow-based quantification (r(2) = 0.77). The SL results are in range with literature values. CONCLUSION: Selective spin labelling MRI of the portal venous and arterial blood supply successfully quantified liver perfusion. This non-invasive technique provides specific arterial and portal venous perfusion imaging and could benefit clinical settings where contrast agents are contraindicated. KEY POINTS: • Perfusion imaging of the liver by Spin Labelling MRI is feasible • Selective Spin Labelling MRI assessed portal venous and arterial liver perfusion separately • Spin Labelling based portal venous liver perfusion showed significant postprandial increase • Spin Labelling based portal perfusion correlated well with phase-contrast based portal perfusion • This non-invasive technique could benefit settings where contrast agents are contraindicated.

Whole-body MRI, including diffusion-weighted imaging, for staging lymphoma: comparison with CT in a prospective multicenter study.

PURPOSE: To compare whole-body magnetic resonance imaging (MRI), including diffusion-weighted imaging (DWI), to computed tomography (CT) for staging newly diagnosed lymphoma. MATERIALS AND METHODS: In all, 108 patients with newly diagnosed lymphoma prospectively underwent whole-body MRI (T1-weighted and T2-weighted short inversion time inversion recovery [n = 108], and DWI [n = 104]) and CT. Ann Arbor stages were assigned according to whole-body MRI and CT findings. Staging disagreements were resolved using bone marrow biopsy, FDG-PET, and follow-up studies. The results were descriptively analyzed. RESULTS: Staging results of whole-body MRI without DWI were equal to those of CT in 66.6%, higher in 24.1%, and lower in 9.3%, with correct/incorrect/unresolved higher staging and incorrect/unresolved lower staging relative to CT in 15/7/4 and 9/1 patient(s), respectively. Staging results of whole-body MRI with DWI were equal to those of CT in 65.4%, higher in 27.9%, and lower in 6.7%, with correct/incorrect/unresolved higher staging and incorrect/unresolved lower staging relative to CT in 18/6/5 and 6/1 patient(s), respectively. CONCLUSION: The results of this study suggest that whole-body MRI staging equals CT staging in the majority of patients with newly diagnosed lymphoma. No advantage of additional DWI was demonstrated. Whole-body MRI can be a good alternative to CT if radiation exposure should be avoided.

The role of routine preoperative EUS when performed after contrast enhanced CT in the diagnostic work-up in patients suspected of pancreatic or periampullary cancer.

BACKGROUND: In patients suspected of pancreatic or periampullary cancer, abdominal contrast-enhanced computed tomography (CT) is the standard diagnostic modality. A supplementary endoscopic ultrasonography (EUS) is often performed, although there is only limited evidence of its additional diagnostic value. The aim of the study is to evaluate the additional diagnostic value of EUS over CT in deciding on exploratory laparotomy in patients suspected of pancreatic or periampullary cancer. METHODS: We retrospectively analyzed 86 consecutive patients who routinely underwent CT and EUS before exploratory laparotomy with or without pancreatoduodenectomy for suspected pancreatic or periampullary carcinoma between 2007 and 2010. Primary outcomes were visibility of a mass, resectability on CT/EUS and resection with curative intent. RESULTS: A mass was visible on CT in 72/86 (84%) patients. In these 72 patients, EUS demonstrated a mass in 64/72 (89%) patients. Resectability was accurately predicted by CT in 65/72 (90%) and by EUS in 58/72 (81%) patients. In 14/86 (16%) patients no mass was seen on CT. EUS showed a mass in 12/14 (86%) of these patients. A malignant lesion was histological proven in 11/12 (92%) of these patients. Overall, resectability was accurately predicted by CT and EUS in 90% (77/86) and 84% (72/86), respectively. CONCLUSIONS: In patients with a visible mass on CT, suspected for pancreatic or periampullary cancer, EUS has no additional diagnostic value, does not influence the decision to perform laparotomy and should therefore not be performed routinely. In patients without a visible mass on CT, EUS is useful to confirm the presence of a tumor.

Liver perfusion in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI): comparison of enhancement in Gd-BT-DO3A and Gd-EOB-DTPA in normal liver parenchyma.

PURPOSE: Within-patient comparison of the enhancement patterns of normal liver parenchyma after gadobutrol and gadoxetate disodium, with emphasis on the start of hepatocytic uptake of gadoxetate disodium. MATERIALS AND METHODS: Twenty-one patients (12 female, 9 male) without chronic liver disease underwent 1.5-T contrast-enhanced MRI twice, once with an extracellular contrast agent (gadobutrol) and once with a hepatospecific agent (gadoxetate disodium), using a T1-weighted keyhole sequence. Fifteen whole-liver datasets were acquired up to 5 min for both contrast agents and two additional datasets, up to 20 min, for gadoxetate. Signal intensities (SI) of the parenchyma, aorta and portal vein were measured and analysed relative to pre-contrast parenchymal SI. RESULTS: After gadoxetate, in 29% of the patients the parenchymal SI decreased by ≥5% after the initial vascular-phase-induced peak, while in the other 71% the parenchymal SI remained stable or gradually increased until up to 20 min after the initial peak. The hepatocytic gadoxetate uptake started at a mean of 37.8 s (SD 14.7 s) and not later than 76 s after left ventricle enhancement. CONCLUSION: Parenchymal enhancement due to hepatocytic uptake of gadoxetate can start as early as in the late arterial phase. This may confound the assessment of lesion appearance as compared to extracellular contrast such as gadobutrol. KEY POINTS: Gadoxetate-enhanced liver MRI results in early enhancement of normal parenchyma in patients The start of the hepatobiliary phase coincides with the late arterial phase. This may confound the assessment of lesion appearance compared to extracellular contrast. Different parenchymal enhancement patterns after gadoxetate were found for normal parenchyma.

A step-up approach or open necrosectomy for necrotizing pancreatitis.

BACKGROUND: Necrotizing pancreatitis with infected necrotic tissue is associated with a high rate of complications and death. Standard treatment is open necrosectomy. The outcome may be improved by a minimally invasive step-up approach. METHODS: In this multicenter study, we randomly assigned 88 patients with necrotizing pancreatitis and suspected or confirmed infected necrotic tissue to undergo primary open necrosectomy or a step-up approach to treatment. The step-up approach consisted of percutaneous drainage followed, if necessary, by minimally invasive retroperitoneal necrosectomy. The primary end point was a composite of major complications (new-onset multiple-organ failure or multiple systemic complications, perforation of a visceral organ or enterocutaneous fistula, or bleeding) or death. RESULTS: The primary end point occurred in 31 of 45 patients (69%) assigned to open necrosectomy and in 17 of 43 patients (40%) assigned to the step-up approach (risk ratio with the step-up approach, 0.57; 95% confidence interval, 0.38 to 0.87; P=0.006). Of the patients assigned to the step-up approach, 35% were treated with percutaneous drainage only. New-onset multiple-organ failure occurred less often in patients assigned to the step-up approach than in those assigned to open necrosectomy (12% vs. 40%, P=0.002). The rate of death did not differ significantly between groups (19% vs. 16%, P=0.70). Patients assigned to the step-up approach had a lower rate of incisional hernias (7% vs. 24%, P=0.03) and new-onset diabetes (16% vs. 38%, P=0.02). CONCLUSIONS: A minimally invasive step-up approach, as compared with open necrosectomy, reduced the rate of the composite end point of major complications or death among patients with necrotizing pancreatitis and infected necrotic tissue. (Current Controlled Trials number, ISRCTN13975868.)

Imaging strategies in the management of oesophageal cancer: what's the role of MRI?

OBJECTIVES: To outline the current role and future potential of magnetic resonance imaging (MRI) in the management of oesophageal cancer regarding T-staging, N-staging, tumour delineation for radiotherapy (RT) and treatment response assessment. METHODS: PubMed, Embase and the Cochrane library were searched identifying all articles related to the use of MRI in oesophageal cancer. Data regarding the value of MRI in the areas of interest were extracted in order to calculate sensitivity, specificity, predictive values and accuracy for group-related outcome measures. RESULTS: Although historically poor, recent improvements in MRI protocols and techniques have resulted in better imaging quality and the valuable addition of functional information. In recent studies, similar or even better results have been achieved using optimised MRI compared with other imaging strategies for T- and N-staging. No studies clearly report on the role of MRI in oesophageal tumour delineation and real-time guidance for RT so far. Recent pilot studies showed that functional MRI might be capable of predicting pathological response to treatment and patient prognosis. CONCLUSIONS: In the near future MRI has the potential to bring improvement in staging, tumour delineation and real-time guidance for RT and assessment of treatment response, thereby complementing the limitations of currently used imaging strategies. KEY POINTS: • MRI's role in oesophageal cancer has been somewhat limited to date. • However MRI's ability to depict oesophageal cancer is continuously improving. • Optimising TN-staging, radiotherapy planning and response assessment ultimately improves individualised cancer care. • MRI potentially complements the limitations of other imaging strategies regarding these points.

CT-colonography after incomplete colonoscopy: what is the diagnostic yield?

BACKGROUND: Computed tomography-colonography is a diagnostic modality that can be used when the colon is not completely intubated during colonoscopy. It may have the additional advantage that information on extracolonic lesions can be obtained. OBJECTIVE: The aim of this study was to investigate the yield of CT-colonography of relevant intra- and extracolonic findings in patients after incomplete colonoscopy. DESIGN: This was an observational, retrospective study. DATA SOURCES: Data were be obtained from standardized radiology and endoscopy reports and electronic medical records. STUDY SELECTION: In total, 136 consecutive CT-colonographies performed after incomplete colonoscopy were evaluated. MAIN OUTCOME MEASURES: All intra- and extracolonic findings on CT-colonography were recorded and interpreted for clinical relevance, and it was determined whether further diagnostic and/or therapeutic workup was indicated. RESULTS: Major indications for colonoscopy included iron-deficiency anemia (25.7%), hematochezia (20.6%), change in bowel habits (18.4%), and colorectal cancer screening or surveillance (11.0%). Major reasons for incomplete colonoscopy were a fixed colon (34.6%) and strong angulation of the sigmoid colon (17.6%). Introduction of the colonoscope was limited to the left-sided colon in 53.7% of cases. Incomplete colonoscopy detected colorectal cancer in 12 (8.8%) patients and adenomatous polyps in 27 (19.9%) patients. CT-colonography after incomplete colonoscopy additionally revealed 19 polyps in 15 (11.0%) and a nonsynchronous colorectal cancer in 4 (2.9%) patients. CT-colonography also detected extracolonic findings with clinical consequences in 8 (5.9%) patients, including fistulizing diverticulitis (n = 3), gastric tumor (n = 2), liver abscess (n = 1), osteomyelitis (n = 1), and an infected embolus in both renal arteries (n = 1). LIMITATIONS: This study was limited by the lack of confirmation of intraluminal CT-colonography findings in a subset of patients. CONCLUSIONS: Computed tomography-colonography can be of added value in patients with incomplete colonoscopy, because it revealed 27 relevant additional (both intra- and extracolonic) lesions in 19.1% of patients. In cases where CT-colonography detected colorectal cancer after incomplete colonoscopy, it can also be used for staging purposes.

Clinical Outcomes of Biliary Drainage in Patients with Malignant Biliary Obstruction Caused by Colorectal Cancer Metastases.

BACKGROUND AND AIM: Malignant biliary obstruction is an ominous complication of metastatic colorectal cancer (mCRC) that is challenging to solve. Biliary drainage can be performed to relieve symptoms of jaundice, treat cholangitis, or enable palliative systemic therapy. The aim of this study is to evaluate clinical outcomes of biliary drainage of malignant biliary obstruction in mCRC patients. METHODS: Consecutive patients with malignant biliary obstruction due to mCRC who underwent endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography were included. Patient, disease, and procedural characteristics and outcomes were retrospectively collected from electronic medical records. Radiological data were prospectively reassessed. Main outcome was functional success, i.e. achievement of the intended goal of biliary drainage. Prognostic factors for functional success and survival were assessed. RESULTS: Thirty-seven patients were included. Functional success was achieved in 18 (50%) patients. Seventeen (46%) patients experienced adverse events (suspected to be) related to the procedure. Median overall survival after biliary drainage was 61 days (IQR 31-113). No prognostic factors of functional success were identified. Performance status, presence of the primary tumor, ascites, ≥ 5 intrahepatic metastases, estimated hepatic invasion of > 50% and above-median levels of bilirubin and lactate dehydrogenase were significantly associated with poorer survival. Improved survival was seen in patients with technical, functional, or biochemical success, and with subsequent oncologic treatment. CONCLUSIONS: Functional successful biliary drainage was achieved in half of the patients. Adverse events also occurred in nearly half of the patients. We observed a significantly longer survival in whom biliary drainage allowed palliative oncologic therapy.

Preoperative imaging of colorectal liver metastases after neoadjuvant chemotherapy: a meta-analysis.

BACKGROUND: Chemotherapy treatment induces parenchymal changes that potentially affect imaging of CRLM. The purpose of this meta-analysis was to provide values of diagnostic performance of magnetic resonance imaging (MRI), computed tomography (CT), fluorodeoxyglucose positron emission tomography (FDG-PET), and FDG-PET/CT for preoperative detection of colorectal liver metastases (CRLM) in patients treated with neoadjuvant chemotherapy. METHODS: A comprehensive search was performed for original articles published from inception to 2011 assessing diagnostic performance of MRI, CT, FDG-PET, or FDG-PET/CT for preoperative evaluation of CRLM following chemotherapy. Intraoperative findings and/or histology were used as reference standard. For each imaging modality we calculated pooled sensitivities for patients who received neoadjuvant chemotherapy as well as for chemonaive patients, defined as number of malignant lesions detected divided by number of malignant lesions as confirmed by the reference standard. RESULTS: A total of 11 papers, comprising 223 patients with 906 lesions, were included. Substantial variation in study design, patient characteristics, imaging features, and reference tests was observed. Pooled sensitivity estimates of MRI, CT, FDG-PET, and FDG-PET/CT were 85.7% (69.7-94.0%), 69.9% (65.6-73.9%), 54.5% (46.7-62.1%), and 51.7% (37.8-65.4%), respectively. In chemonaive patients, sensitivity rates were 80.5% (67.0-89.4%) for CT, 81.3% (64.1-91.4%) for FDG-PET, and 71.0% (64.3-76.9%) for FDG-PET/CT. Specificity could not be calculated because of non-reporting of "true negative lesions." CONCLUSION: In the neoadjuvant setting, MRI appears to be the most appropriate imaging modality for preoperative assessment of patients with CRLM. CT is the second-best diagnostic modality and should be used in the absence of MRI. Diagnostic accuracy of FDG-PET and PET-CT is strongly affected by chemotherapy.

MRI for staging lymphoma: whole-body or less?

PURPOSE: To assess whether whole-body MRI detects more clinically relevant lesions (i.e., leading to a change in Ann Arbor stage) than an MRI protocol that only includes the head/neck and trunk (i.e., from cranial vertex to groin, excluding the arms) in patients with lymphoma. MATERIALS AND METHODS: One hundred consecutive patients with newly diagnosed lymphoma prospectively underwent T1-weighted and T2-weighted short inversion time inversion recovery whole-body MRI. The number of lymphomatous sites at MRI with a field of view (FOV) limited to the head/neck and trunk, and the additional number of lymphomatous sites at whole-body MRI and their influence on Ann Arbor stage were determined. RESULTS: At MRI with a FOV limited to the head/neck and trunk, 507 sites were classified as lymphomatous. At whole-body MRI, 7 additional sites outside the head/neck and trunk in 7 patients (7.0%; 95% confidence interval: 3.4-13.8%) were classified as lymphomatous, but Ann Arbor stage never changed. CONCLUSION: Whole-body MRI did not detect any clinically relevant lesions outside the FOV of an MRI protocol that only includes the head/neck and trunk. Therefore, it may be sufficient to only include the head/neck and trunk when using MRI for staging lymphoma.

A comparison of the accuracy of ultrasound and computed tomography in common diagnoses causing acute abdominal pain.

OBJECTIVES: Head-to-head comparison of ultrasound and CT accuracy in common diagnoses causing acute abdominal pain. MATERIALS AND METHODS: Consecutive patients with abdominal pain for >2 h and <5 days referred for imaging underwent both US and CT by different radiologists/radiological residents. An expert panel assigned a final diagnosis. Ultrasound and CT sensitivity and predictive values were calculated for frequent final diagnoses. Effect of patient characteristics and observer experience on ultrasound sensitivity was studied. RESULTS: Frequent final diagnoses in the 1,021 patients (mean age 47; 55% female) were appendicitis (284; 28%), diverticulitis (118; 12%) and cholecystitis (52; 5%). The sensitivity of CT in detecting appendicitis and diverticulitis was significantly higher than that of ultrasound: 94% versus 76% (p < 0.01) and 81% versus 61% (p = 0.048), respectively. For cholecystitis, the sensitivity of both was 73% (p = 1.00). Positive predictive values did not differ significantly between ultrasound and CT for these conditions. Ultrasound sensitivity in detecting appendicitis and diverticulitis was not significantly negatively affected by patient characteristics or reader experience. CONCLUSION: CT misses fewer cases than ultrasound, but both ultrasound and CT can reliably detect common diagnoses causing acute abdominal pain. Ultrasound sensitivity was largely not influenced by patient characteristics and reader experience.

Diagnostic accuracy of computed tomography for colon cancer staging: a systematic review.

BACKGROUND: Computed Tomography (CT) is a frequently used staging modality for colon cancer patients in clinical practice. Our aim was to systemically review the available literature on diagnostic accuracy of CT for TNM staging of colon cancer. METHODS: A systematic review of literature was performed. PubMed was searched using MeSH terms with the following search terms: "Tomography, X-Ray Computed" or "Tomography, Spiral Computed" and Colonic Neoplasms. Studies on rectal cancer and studies without separate analyses for the colon were excluded. We identified 779 publications, of which 11 were included for review. Overall and sample-size-weight sensitivity, specificity, accuracy, true-positive, true-negative, false-positive, false-negative, positive and negative predictive values were calculated for T, N and M stages. RESULTS: In the 11 studies, a total of 753 patients with 759 colon cancers underwent CT for staging. Sample-size-weighted sensitivity, specificity and accuracy for T-staging was 77%, 3% and 67%, respectively; for N-staging 76%, 55% and 69%, respectively; and for M-staging 85%, 98% and 95%, respectively. Additional clinical findings were reported in 59/372 (16%) patients, with 12 having a malignant and 47 a benign origin. CONCLUSIONS: While accuracy of CT for TN-staging of colon cancer is only reasonable, the real value of CT is its high accuracy to detect distant metastases.

Newly diagnosed lymphoma: initial results with whole-body T1-weighted, STIR, and diffusion-weighted MRI compared with 18F-FDG PET/CT.

OBJECTIVE: The purpose of this study was to compare whole-body MRI including diffusion-weighted imaging (DWI) with (18)F-FDG PET/CT in the staging of newly diagnosed lymphoma. SUBJECTS AND METHODS: Twenty-two consecutively registered patients with newly diagnosed lymphoma prospectively underwent whole-body MRI (22 with T1-weighted, STIR, and DWI sequences and 21 with T1-weighted and STIR sequences but not DWI) and FDG PET/CT. Whole-body MRI-DWI was independently evaluated by two blinded observers. Interobserver agreement was assessed, and whole-body MRI-DWI was compared with FDG PET/CT. RESULTS: The kappa values for interobserver agreement on whole-body MRI-DWI for all nodal regions together and for all extranodal regions together were 0.676 and 0.452. The kappa values for agreement between whole-body MRI-DWI and FDG PET/CT for all nodal regions together and for all extranodal regions together were 0.597 and 0.507. Ann Arbor stage according to whole-body MRI-DWI findings was concordant with that of FDG PET/CT findings in 77% (17/22) of patients. Understaging and overstaging relative to the findings with FDG PET/CT occurred in 0% (0/22) and 23% (5/22) of cases. In the care of 9% (2/22) of patients, overstaging with whole-body MRI-DWI relative to staging with FDG PET/CT would have had therapeutic consequences. CONCLUSION: Our early results indicate that overall interobserver agreement on whole-body MRI-DWI findings is moderate to good. Overall agreement between whole-body MRI-DWI and FDG PET/CT is moderate. In the care of patients with newly diagnosed lymphoma, staging with whole-body MRI-DWI does not result in underestimation of stage relative to the results with FDG PET/CT. In a minority of patients, reliance on whole-body MRI-DWI leads to clinically important overstaging relative to the results with FDG PET/CT. FDG PET/CT remains the reference standard for lymphoma staging until larger-scale studies show that use of whole-body MRI-DWI results in correct staging in this minority of cases.

The Role of CT in Assessment of Extraregional Lymph Node Involvement in Pancreatic and Periampullary Cancer: A Diagnostic Accuracy Study.

Purpose: To investigate the diagnostic accuracy of CT in assessing extraregional lymph node metastases in pancreatic head and periampullary cancer. Materials and Methods: This prospective observational cohort study was performed at two tertiary hepatopancreatobiliary (HPB) referral centers between March 2013 and December 2014. Patients undergoing pancreatoduodenectomy or bypass surgery with or without palliative radiofrequency ablation were included. Extraregional lymph node involvement was defined as positive lymph nodes in the aortocaval window. Two expert HPB radiologists assessed aortocaval lymph nodes at preoperative CT according to a standardized protocol. All tissue from the aortocaval window was collected intraoperatively. Positive histopathologic finding was the reference standard. Analysis of predictive values and diagnostic accuracy was performed. Results: A total of 198 consecutive patients (mean age, 66 years; range, 39-86 years; 105 men) with pancreatic head or periampullary carcinoma were included. In 70% of patients, a pancreatoduodenectomy was performed, 4% underwent total pancreatectomy, 4% underwent radiofrequency ablation, and 22% underwent bypass surgery. Forty-four patients (22%) had histologically positive aortocaval lymph nodes. Negative predictive value of CT in assessing aortocaval lymph nodes was 80% for both observers, and positive predictive value was 31%-33%. Overall diagnostic accuracy was 69%-70%. Conclusion: CT has a low diagnostic accuracy in assessing extraregional lymph node metastases in patients suspected of having pancreatic or periampullary cancer.Keywords: CT, Abdomen/GI, Pancreas, Oncology© RSNA, 2021.