Differential Diagnosis and Molecular Stratification of Gastrointestinal Stromal Tumors on CT Images Using a Radiomics Approach.

Treatment planning of gastrointestinal stromal tumors (GISTs) includes distinguishing GISTs from other intra-abdominal tumors and GISTs' molecular analysis. The aim of this study was to evaluate radiomics for distinguishing GISTs from other intra-abdominal tumors, and in GISTs, predict the c-KIT, PDGFRA, BRAF mutational status, and mitotic index (MI). Patients diagnosed at the Erasmus MC between 2004 and 2017, with GIST or non-GIST intra-abdominal tumors and a contrast-enhanced venous-phase CT, were retrospectively included. Tumors were segmented, from which 564 image features were extracted. Prediction models were constructed using a combination of machine learning approaches. The evaluation was performed in a 100 × random-split cross-validation. Model performance was compared to that of three radiologists. One hundred twenty-five GISTs and 122 non-GISTs were included. The GIST vs. non-GIST radiomics model had a mean area under the curve (AUC) of 0.77. Three radiologists had an AUC of 0.69, 0.76, and 0.84, respectively. The radiomics model had an AUC of 0.52 for c-KIT, 0.56 for c-KIT exon 11, and 0.52 for the MI. The numbers of PDGFRA, BRAF, and other c-KIT mutations were too low for analysis. Our radiomics model was able to distinguish GISTs from non-GISTs with a performance similar to three radiologists, but less observer dependent. Therefore, it may aid in the early diagnosis of GIST, facilitating rapid referral to specialized treatment centers. As the model was not able to predict any genetic or molecular features, it cannot aid in treatment planning yet.

Calcification of the Aorta-Iliac Trajectory as a Risk Factor for Anastomotic Leakage in Colorectal Surgery: Individual Patient Data Meta-Analysis and Systematic Review.

OBJECTIVE: The purpose of this review is to evaluate the relevance of vascular calcification as a potential risk factor for anastomotic leakage in colorectal surgery. METHOD: The Embase, Medline, PubMed, and Cochrane databases and Google Scholar were systematically searched. Studies that assessed calcification of the aorta-iliac trajectory in patients who underwent colorectal surgery were included. An independent patient data meta-analysis was performed as follows: based on the heterogeneity of the study population, a "random-effects model" or "fixed-effects model" was used to perform a multivariable logistic regression and calculate pooled Odds Ratios (OR) and 95% confidence intervals (CI). Heterogeneity was assessed using the Q-test and I2-test. RESULTS: From a total of 457 articles retrieved, eight fell within the scope of the review, with a total of 2010 patients. Anastomotic leakage was found at a mean rate of 11.1% (SD 4.9%). In these eight studies, four different calcification scoring methods were used, which made a single structured meta-analysis not feasible. Therefore, an independent patient data meta-analysis on the most frequently used calcification scoring method was performed, including three studies with a total of 396 patients. After multivariable analyses, no significant association was found between anastomotic leakage and the amount of calcification in the aorta-iliac trajectory. The remaining three scoring methods were evaluated. In four of the five studies, vascular calcification was associated with anastomotic leakage after colorectal surgery. CONCLUSION: In contrast to previous studies, an individual patient data meta-analysis found no association between calcification and anastomotic leakage in colorectal surgery after multivariable analysis that considered a single calcification measurement method. In addition, this study demonstrated several scoring methods for arterial calcification and the need for a standardized technique. Therefore, the authors would recommend prospective studies using a calcification scoring method that includes grade of stenosis due to its potential to preoperatively improve perfusion by endovascular treatment.

Response to Letter: Intrapatient Comparison of the Hepatobiliary Phase of Gd-BOPTA and Gd-EOB-DTPA in the Differentiation of HCA From FNH.

LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY STAGE: 3 J. Magn. Reson. Imaging 2020;52:1281-1282.

The yield of chest computed tomography in patients with locally advanced pancreatic cancer.

OBJECTIVE: To evaluate the incidence of pulmonary metastases on chest computed tomography (CT) in patients with locally advanced pancreatic cancer (LAPC). METHODS: All patients diagnosed with LAPC in a single tertiary center (Erasmus MC) between October 2011 and December 2017 were reviewed. The staging chest CT scan and follow-up chest CT scans were evaluated. Pulmonary nodules were divided into three categories: apparent benign, too small to characterize, and apparent malignant. RESULTS: In 124 consecutive patients diagnosed with LAPC, 119 (96%) patients underwent a staging chest CT scan at the initial presentation. In 88 (74%) patients no pulmonary nodules were found; in 16 (13%) patients an apparent benign pulmonary nodule was found, and in 15 (13%) patients a pulmonary nodule too small to characterize was found. Follow-up chest CT scan(s) were performed in 111 (93%) patients. In one patient with either no pulmonary nodule or an apparent benign pulmonary nodule at initial staging, an apparent malignant pulmonary nodule was found on a follow-up chest CT scan. However, a biopsy of the nodule was inconclusive. Of 15 patients in whom a pulmonary nodule too small to characterize was found at staging, 12 (80%) patients underwent a follow-up CT scan; in 4 (33%) of these patients, an apparent malignant pulmonary nodule was found. CONCLUSION: In patients with LAPC in whom at diagnosis a chest CT scan revealed either no pulmonary nodules or apparent benign pulmonary nodules, routine follow-up chest CT scans is not recommended. Patients with pulmonary nodules too small to characterize are at risk to develop apparent malignant pulmonary nodules during follow-up.

Performance of Contrast-Enhanced Sonography Versus MRI With a Liver-Specific Contrast Agent for Diagnosis of Hepatocellular Adenoma and Focal Nodular Hyperplasia.

OBJECTIVE. The purpose of this article is to compare contrast-enhanced sonography (CEUS) with sulfur hexafluoride with MRI with the liver-specific contrast agent gadobenate dimeglumine in the diagnosis of hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH) in a cohort of consecutive patients. MATERIALS AND METHODS. Patients referred to a tertiary center for hepatobiliary disease who had suspected HCA or FNH on MRI performed with an extracellular gadolinium-based contrast agent underwent a prospective workup including CEUS and MRI with a liver-specific contrast agent. Diagnosis was definite when the findings of CEUS and MRI with a liver-specific contrast agent were concordant; histopathologic examination (HPE) was performed for cases with discordant findings. Descriptive statistics and the association between categoric variables were presented as numbers and percentages and were assessed using the Fisher exact test. The primary analysis was patient based. Sensitivity, specificity, and AUC and predictive values for the diagnosis of HCA and FNH were calculated separately for CEUS and MRI with a liver-specific contrast agent. RESULTS. A total of 181 patients were selected for the first analysis. Findings from CEUS and MRI with a liver-specific contrast agent were concordant for 132 patients (73%) and discordant for 49 (27%). HPE was performed for 26 of the 49 patients with discordant findings (53%), with findings indeterminate for two of these patients, the findings of MRI with a liver-specific contrast agent correct for 21 of the remaining 24 patients (87.5%), and the findings of CEUS correct for three of these 24 patients (12.5%) (p < 0.05). For further analysis, 156 patients with concordant findings or HPE-proven cases were included. For CEUS, the sensitivity and specificity for the diagnosis of HCA and FNH were 85% and 87%, respectively; the ROC AUC value was 0.856; and the positive predictive value and negative predictive value were 79% and 90%, respectively. For MRI with a liver-specific contrast agent, the sensitivity and specificity were 95% each, the ROC AUC value was 0.949, and the positive predictive value and negative predictive value were 92% and 97%, respectively, for the diagnosis of HCA and FNH. CONCLUSION. The findings of CEUS and MRI with a liver-specific contrast agent showed fair agreement for the diagnosis of HCA and FNH. MRI with a liver-specific contrast agent is diagnostically correct significantly more often than CEUS in cases with discordant findings that are HPE proven.

Hepatic angiomyolipoma: an international multicenter analysis on diagnosis, management and outcome.

BACKGROUND: Hepatic angiomyolipoma (HAML) may easily be misdiagnosed as a malignancy. The study aim was to assess diagnostic dilemmas, clinical management and outcome of this rare tumor. METHODS: This retrospective international multicenter study included all patients with pathologically proven HAML diagnosed between 1997 and 2017. Data on patient characteristics, diagnostic work-up, management and follow-up were analyzed. RESULTS: Thirty-eight patients were included, 32 female. Median age was 56yrs (i.q.r. 43-64) and median HAML-diameter was 57.5 mm (i.q.r. 38.5-95.3). Thirty patients had undergone CT and 27/38 MRI of the liver, diagnostic biopsy was performed in 19/38. Initial diagnosis was incorrect in 15/38 patients, of which 13 were thought to have malignancy. In 84% biopsy resulted in a correct preoperative diagnosis. Twenty-nine patients were managed with surgical resection, 4/38 with surveillance and 3/38 with liver transplantation. Recurrence after resection occurred in two cases. No HAML related deaths or progression to malignancy were documented. CONCLUSION: HAML diagnosis proved problematic even in hepatobiliary expertise centers. Biopsy is indicated and may provide valuable additional information when HAML diagnosis is considered on cross-sectional imaging, especially when surgical resection imposes a risk of complications. Conservative management with regular imaging follow-up might be justified when biopsy confirms (classic type) HAML.

Intrapatient Comparison of the Hepatobiliary Phase of Gd-BOPTA and Gd-EOB-DTPA in the Differentiation of Hepatocellular Adenoma From Focal Nodular Hyperplasia.

BACKGROUND: Current imaging guidelines do not specify the preferred hepatobiliary contrast agent when differentiating hepatocellular adenoma (HCA) from focal nodular hyperplasia (FNH) on MRI. PURPOSE: To analyze intrapatient differences in the hepatobiliary phase (HBP) after use of both gadobenate dimeglumine (Gd-BOPTA) and gadoxetic acid (Gd-EOB-DTPA)-enhanced MRI to differentiate HCA from FNH. STUDY TYPE: Retrospective. POPULATION: Patients who underwent both Gd-BOPTA and Gd-EOB-DTPA-enhanced MRI, including 33 patients with 82 lesions (67 HCA; 15 FNH), with a step-down reference standard of pathology, 20% regression, identical appearance to earlier biopsied lesions, and stringent imaging findings. FIELD STRENGTH/SEQUENCE: 1.5T and 3T HBP of Gd-BOPTA and Gd-EOB-DTPA-enhanced MRI, precontrast fat-suppressed T1 -weighted sequence. ASSESSMENT: Signal intensities relative to the surrounding liver in the HBP were assessed by two observers. STATISTICAL TESTS: Sensitivity and specificity of HCA diagnosis were calculated for both contrast agents. Interobserver agreement was evaluated using Cohen's kappa; differences in degree of certainty for scoring a lesion were calculated by means of the Wilcoxon signed rank test. Differences in signal intensity between Gd-BOPTA and Gd-EOB-DTPA were calculated using McNemar's test. RESULTS: Almost perfect agreement was found between observers for scored signal intensities with both contrast agents. In 30 of the 82 lesions (37%) a difference was observed between contrast agents in the HBP, with Gd-EOB-DTPA proving correct in all but one of the discordant lesions. When distinguishing HCA from FNH, Gd-BOPTA showed a sensitivity of 46% (31/67) and a specificity of 87% (13/15), while the sensitivity and specificity of Gd-EOB-DTPA was 85% (57/67) and 100% (15/15), respectively. A risk of misclassifying HCA as FNH typically occurs for Gd-BOPTA when lesions are intrinsically hyperintense (P < 0.005). DATA CONCLUSION: The HBP of Gd-EOB-DTPA shows superior accuracy in ruling out HCA in comparison with Gd-BOPTA, especially when the lesion is intrinsically hyperintense on T1 -weighted imaging. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:700-710.

Growth of Focal Nodular Hyperplasia is Not a Reason for Surgical Intervention, but Patients Should be Referred to a Tertiary Referral Centre.

BACKGROUND: When a liver lesion diagnosed as focal nodular hyperplasia (FNH) increases in size, it may cause doubt about the initial diagnosis. In many cases, additional investigations will follow to exclude hepatocellular adenoma or malignancy. This retrospective cohort study addresses the implications of growth of FNH for clinical management. METHODS: We included patients diagnosed with FNH based on ≥2 imaging modalities between 2002 and 2015. Characteristics of patients with growing FNH with sequential imaging in a 6-month interval were compared to non-growing FNH. RESULTS: Growth was reported in 19/162 (12%) patients, ranging from 21 to 200%. Resection was performed in 4/19 growing FNHs; histological examination confirmed FNH in all patients. In all 15 conservatively treated patients, additional imaging confirmed FNH diagnosis. No adverse outcomes were reported. No differences were found in characteristics and presentation of patients with growing or non-growing FNH. CONCLUSION: This study confirms that FNH may grow significantly without causing symptoms. A significant increase in size should not have any implications on clinical management if confident diagnosis by imaging has been established by a tertiary benign liver multidisciplinary team. Liver biopsy is only indicated in case of doubt after state-of-the-art imaging. Resection is deemed unnecessary if the diagnosis is confirmed by multiple imaging modalities in a tertiary referral centre.

Management of hepatic angiomyolipoma: A systematic review.

Hepatic Angiomyolipoma (HAML) is a rare mesenchymal liver tumour assumed to be predominantly benign, although incidental cases with malignant behaviour such as invasive growth, recurrence after resection and metastases have been reported. The aim of this systematic review was to assess the biological behaviour, estimate the risk of HAML related mortality and recommend on a justifiable management strategy. We performed a systematic literature search in Embase, Medline, Web-of-Science, Scopus, Pubmed Publisher, Cochrane and Google Scholar. We included all articles published from inception until March 2016 which reported on follow-up of various treatment strategies. We included 18 articles reporting on 292 patients. Male:female ratio was estimated at 1:3 with gender not reported in 31 cases. Of 292 patients 247 were treated with surgery, including one liver transplant, seven with chemotherapy or Sirolimus, three with embolization, and 35 conservatively. Recurrence after resection was described in 6/247 (2.4%) with pathologically proven HAML resulting in metastases and death in 2/247 (mortality rate 0.8%). Progression was described in 6/35 patients treated conservatively (21.4%). Two of 12 patients with malignant behaviour of HAML had an epithelioid-type HAML, of the remaining 10 histological subtype was undefined. With a risk estimate of 0.8% in surgically treated patients HAML related mortality is very low. Biopsy is indicated when imaging is inconclusive. In case of certain HAML diagnosis on imaging conservative management with annual imaging is justified. Resection should be considered in case of symptoms, inconclusive biopsy or growth in follow-up.

Primary Cystic Lesions of the Retrorectal Space: MRI Evaluation and Clinical Assessment.

OBJECTIVE: The purpose of this study was to assess the a priori chance that primary cystic lesions of the retrorectal space are malignant and to investigate MRI characteristics that indicate malignancy. MATERIALS AND METHODS: Patients referred to a center for colorectal surgery were recruited from 2000 to 2014. Lesions were proven by clinical assessment and histopathology. MRI was performed at 1.5 T with examinations evaluated by two radiologists. Interobserver agreement was assessed (Cohen kappa) and differences between malignant and benign lesions calculated (Fisher exact test). RESULTS: Twenty-eight patients (22 women, six men; age range, 18-70 years) with 31 lesions were included. Lesions were categorized as tailgut cysts (n = 16, 52%), teratomas (n = 9, 29%), lesions of colorectal origin (n = 4, 13%), or neurogenic lesions (n = 2, 6%). Five patients (18%) had malignant lesions. Colorectal lesions had the highest percentage of malignancy (3/4, 75%). A solid tissue component was found in all five (100%) malignant lesions and two (8%) of the benign lesions, which were both teratomas (p < 0.05). Sensitivity and specificity for malignancy according to the presence of a solid tissue component was 100% (5/5) and 92% (24/26). For unilocularity, multilocularity, debris, septa, and wall thickening, differences were not significant. Interobserver agreement was excellent (κ = 1) for all characteristics except debris (κ = 0.795). CONCLUSION: The majority of retrorectal cystic lesions are benign. The presence of a solid tissue component should raise suspicion for malignancy.

Small bites versus large bites for closure of abdominal midline incisions (STITCH): a double-blind, multicentre, randomised controlled trial.

BACKGROUND: Incisional hernia is a frequent complication of midline laparotomy and is associated with high morbidity, decreased quality of life, and high costs. We aimed to compare the large bites suture technique with the small bites technique for fascial closure of midline laparotomy incisions. METHODS: We did this prospective, multicentre, double-blind, randomised controlled trial at surgical and gynaecological departments in ten hospitals in the Netherlands. Patients aged 18 years or older who were scheduled to undergo elective abdominal surgery with midline laparotomy were randomly assigned (1:1), via a computer-generated randomisation sequence, to receive small tissue bites of 5 mm every 5 mm or large bites of 1 cm every 1 cm. Randomisation was stratified by centre and between surgeons and residents with a minimisation procedure to ensure balanced allocation. Patients and study investigators were masked to group allocation. The primary outcome was the occurrence of incisional hernia; we postulated a reduced incidence in the small bites group. We analysed patients by intention to treat. This trial is registered at Clinicaltrials.gov, number NCT01132209 and with the Nederlands Trial Register, number NTR2052. FINDINGS: Between Oct 20, 2009, and March 12, 2012, we randomly assigned 560 patients to the large bites group (n=284) or the small bites group (n=276). Follow-up ended on Aug 30, 2013; 545 (97%) patients completed follow-up and were included in the primary outcome analysis. Patients in the small bites group had fascial closures sutured with more stitches than those in the large bites group (mean number of stitches 45 [SD 12] vs 25 [10]; p<0·0001), a higher ratio of suture length to wound length (5·0 [1·5] vs 4·3 [1·4]; p<0·0001) and a longer closure time (14 [6] vs 10 [4] min; p<0·0001). At 1 year follow-up, 57 (21%) of 277 patients in the large bites group and 35 (13%) of 268 patients in the small bites group had incisional hernia (p=0·0220, covariate adjusted odds ratio 0·52, 95% CI 0·31-0·87; p=0·0131). Rates of adverse events did not differ significantly between groups. INTERPRETATION: Our findings show that the small bites suture technique is more effective than the traditional large bites technique for prevention of incisional hernia in midline incisions and is not associated with a higher rate of adverse events. The small bites technique should become the standard closure technique for midline incisions. FUNDING: Erasmus University Medical Center and Ethicon.

MRI features of inflammatory hepatocellular adenomas on hepatocyte phase imaging with liver-specific contrast agents.

PURPOSE: To evaluate the presentation of inflammatory hepatocellular adenomas (HCAs) on hepatocyte phase MRI. MATERIALS AND METHODS: We retrospectively reviewed the MRI features of histologically proven HCAs on hepatocyte phase imaging. Twenty-one lesions (17 with inflammatory subtype) were scanned with gadobenate dimeglumine. Signal intensities of the lesions were assessed in the hepatocyte phase and on the T1-weighted sequences before contrast. RESULTS: After gadobenate dimeglumine injection, 71% (12/17) of the inflammatory HCAs showed areas of iso- or hyperintensity to the surrounding liver in the hepatocyte phase. In 82% (10/12) of the iso- or hyperintense lesions, this was found over more than 75% of the lesion surface. None of the noninflammatory HCAs showed areas of iso- or hyperintensity to the surrounding liver in the hepatocyte phase. From these 12, 7 were hyperintense on T1-weighting before contrast due to liver steatosis, 2 due to intrinsic hyperintensity (on the in-phase sequence), and 3 were isointense. CONCLUSION: In contrast to noninflammatory HCAs, inflammatory HCAs can show areas of iso- to hyperintensity to the surrounding liver in the hepatocyte phase; therefore, other typical imaging features should also be used to distinguish between HCAs and FNHs.

Chronic lower urinary tract symptoms in women: classification of abnormalities and value of dedicated MRI for diagnosis.

OBJECTIVE: Chronic lower urinary tract symptoms are common in women. We present a classification of abnormalities that can be considered in the differential diagnosis for lower urinary tract symptoms and can show the value of dedicated state-of-the art MRI in the workup of patients. CONCLUSION: Dedicated MRI tailored to patient symptoms and clinical findings has the potential to map out morphologic causes and categorize dysfunctional conditions from those that are truly nonmorphologic.

Non-contrast short MRI surveillance for HCC screening: the study protocol of the SMS-HCC prospective multicenter study.

Hepatocellular carcinoma (HCC) comprises 75 to 85% of all primary liver cancers. Current guidelines recommend a biannual HCC surveillance using ultrasound (US) for high-risk patients. However, due to its low sensitivity for detection of early-stage HCC lesions, there is an urgency for more sensitive surveillance tools. Here, we describe the potential of a short MRI surveillance (SMS) protocol for HCC, including axial T1-weighted in-out phase, fat-saturated T2-weighted, and diffusion-weighted sequences. In this prospective, multicenter, patient cohort study, patients will be recruited from existing HCC surveillance cohorts of six medical centers in The Netherlands. Surveillance patients who undergo biannual US, will be invited for SMS on the same day for 3 years. In case of a suspicious finding on either US or SMS, patients will be invited for a full MRI liver protocol including gadolinium-based contrast agent intravenous injection within 2 weeks. To our knowledge, this will be the first study to perform a head-to-head comparison with a paired US-MRI design. We hypothesize that the sensitivity of SMS for detection of early-stage HCC will be higher than that of US leading to improved survival of surveillance patients through timely HCC diagnosis. Furthermore, we hypothesize that the SMS-HCC protocol will prove cost-effective.Relevance statement The US sensitivity for detecting early-stage HCC has been reported to be less than 50%. We expect that the proposed SMS will detect at least twice as many early-stage HCC lesions and therefore prove to be cost-effective. Key points • The low sensitivity of US necessitates better imaging tools for HCC screening.• This is the first study with a paired US-MRI design.• This design will allow a head-to-head comparison in both diagnostics and patient-acceptance.• We expect that SMS can contribute to a higher survival rate.

Evaluation of Hepatocellular Carcinoma Surveillance with Contrast-enhanced MRI in a High-Risk Western European Cohort.

AIM: To investigate the utilization of MRI using a MRI liver protocol with extracellular contrast-enhanced series for hepatocellular carcinoma (HCC) surveillance in high-risk patients. METHODS: Consecutive high-risk patients of a western European cohort who underwent repeated liver MRI for HCC screening were included. Lesions were registered according to the Liver Reporting & Data System (LIRADS) 2018. HCC was staged as very early stage HCC (BCLC stage 0) and more advanced stages of HCC (BCLC stage A-D). Differences in time interval between MRI's for BCLC stage 0 and stage A-D were calculated with the Mann-Whitney U test. The HCC cumulative incidence at one-, three- and five years was calculated with the Kaplan Meier estimator. RESULTS: From 2010 to 2019 a total of 240 patients were included (71% male; median age: 57 years; IQR: 50-64 years) with 1350 MRI's. Most patients (83 %) had cirrhosis with hepatitis C as the most common underlying cause. Patients underwent on average four MRI's (IQR: 3-7). Forty-two patients (17.5%) developed HCC (52 HCC lesions: 43 LIRADS-5, eight LIRADS-4, and one LIRADS-TIV). Eighteen patients (43%) had BCLC stage 0 HCC with a significant shorter screening time interval (10 months; IQR: 6-21) compared to patients with BCLC stage A-D (21 months; IQR: 10-32) (p = 0.03). Thirty seven percent of patients with a LIRADS-3 lesion (n=43) showed HCC development within twelve months (median: 7.4 months). One, three- and five-year HCC cumulative incidence in cirrhotic patients was 1%, 10% and 17%, respectively. CONCLUSION: High-risk patients who underwent surveillance with contrast-enhanced MRI developed HCC in 17.5 % during a follow up period of over 4 years median. Very early stage HCC was seen in compensated cirrhosis after a median time interval of 10 months. Later stages of HCC were related to prolonged screening time interval (median 21 months).

18 F-FDG PET/MRI for restaging esophageal cancer after neoadjuvant chemoradiotherapy.

PURPOSE: The purpose of this study was to investigate whether 18F-fluorodeoxyglucose ( 18 F-FDG) PET/MRI may potentially improve tumor detection after neoadjuvant chemoradiotherapy (nCRT) for esophageal cancer. METHODS: This was a prospective, single-center feasibility study. At 6-12 weeks after nCRT, patients underwent standard 18 F-FDG PET/computed tomography (CT) followed by PET/MRI, and completed a questionnaire to evaluate burden. Two teams of readers either assessed the 18 F-FDG PET/CT or the 18 F-FDG PET/MRI first; the other scan was assessed 1 month later. Maximum standardized uptake value corrected for lean body mass (SUL max ) and mean apparent diffusion coefficient (ADC mean ) were measured at the primary tumor location. Histopathology of the surgical resection specimen served as the reference standard for diagnostic accuracy calculations. When patients had a clinically complete response and continued active surveillance, response evaluations until 9 months after nCRT served as a proxy for ypT and ypN (i.e. 'ycT' and 'ycN'). RESULTS: In the 21 included patients [median age 70 (IQR 62-75), 16 males], disease recurrence was found in the primary tumor in 14 (67%) patients (of whom one ypM+, detected on both scans) and in locoregional lymph nodes in six patients (29%). Accuracy (team 1/team 2) to detect yp/ycT+ with 18 F-FDG PET/MRI vs. 18 F-FDG PET/CT was 38/57% vs. 76/61%. For ypN+, accuracy was 63/53% vs. 63/42%, resp. Neither SUL max (both scans) nor ADC mean were discriminatory for yp/ycT+ . Fourteen of 21 (67%) patients were willing to undergo a similar 18 F-FDG PET/MRI examination in the future. CONCLUSION: 18 F-FDG PET/MRI currently performs comparably to 18 F-FDG PET/CT. Improvements in the scanning protocol, increasing reader experience and performing serial scans might contribute to enhancing the accuracy of tumor detection after nCRT using 18 F-FDG PET/MRI. TRIAL REGISTRATION: Netherlands Trial Register NL9352.

Is restaging with chest and abdominal CT scan after neoadjuvant chemoradiotherapy for locally advanced rectal cancer necessary?

BACKGROUND: There is no evidence regarding restaging of patients with locally advanced rectal cancer after a long course of neoadjuvant radiotherapy with or without chemotherapy. This study evaluated the value of restaging with chest and abdominal computed tomographic (CT) scan after radiotherapy. METHODS: Between January 2000 and December 2010, all newly diagnosed patients in our tertiary referral hospital, who underwent a long course of radiotherapy for locally advanced rectal cancer, were analyzed. Patients were only included if they had chest and abdominal imaging before and after radiotherapy treatment. RESULTS: A total of 153 patients who met the inclusion criteria and were treated with curative intent were included. A change in treatment strategy due to new findings on the CT scan after radiotherapy was observed in 18 (12%) of 153 patients. Twelve patients (8%) were spared rectal surgery due to progressive metastatic disease. CONCLUSIONS: Restaging with a chest and abdominal CT scan after radiotherapy for locally advanced rectal cancer is advisable because additional findings may alter the treatment strategy.

Is bone scintigraphy indicated in surgical work-up for hepatocellular carcinoma patients?

BACKGROUND: Patients with hepatocellular carcinoma (HCC) undergo extensive staging investigations when being assessed for surgical resection. The aim of this study was to assess the use and yield of baseline bone scintigraphy in patients with HCC necessitating high-risk surgical resection. MATERIAL AND METHODS: All patients diagnosed with HCC between 2000 and 2010 within a tertiary referral center were reviewed. Recurrence and survival rates were compared between patients with and without bone scintigraphy in their preoperative work-up. RESULTS: A total of 366 patients were diagnosed with resectable HCC. In the work-up for resection 137 HCC patients (41%) underwent bone scintigraphy, which showed bone metastases in 3 (2%). There was no significant difference in long-term survival between patients with and without bone scintigraphy. None of the patients with a positive bone scintigraphy died due to skeletal bone metastases. Only one patient had an indication for bone scintigraphy based on clinical suspicion. Two patients were found to have asymptomatic skeletal metastases prior to surgery. Symptomatic skeletal metastases were identified at an estimated cost of €27,008 per case. CONCLUSIONS: Clinically unsuspicious bone lesions turned out to be metastases in two patients, with an estimated cost of €27,008 per case. Recurrence rate and disease-free and overall survival showed no significant difference between patients with and without preoperative baseline bone scintigraphy. There is no justification for routine preoperative bone scintigraphy to detect asymptomatic skeletal metastases in patients with resectable HCC.

Chronic anal and perianal pain resolved with MRI.

OBJECTIVE: The purpose of this study was to assess the diagnostic value of anorectal MRI in the care of patients with chronic anal and perianal pain but without findings of abnormalities in the clinical workup. MATERIALS AND METHODS: Patients referred from a tertiary department of colorectal surgery to the MRI unit with clinically occult chronic anal and perianal pain were included. MRI of the anorectum was performed with an endoanal or pelvic phased-array coil. The images from all examinations were read by two radiologists. MRI findings were correlated with clinical follow-up data. RESULTS: The study group (103 patients) was stratified into patients with no history of anorectal disease (n = 60) and those who had a history of surgery for anorectal disease (n = 43). MRI findings suggested the final diagnoses in 40 patients (39%). These diagnoses were 28 cases of suppurative lesions (27%), 11 cases of painful scarring of the anus (11%), and one case of metastasis to the sacrum (1%). Suppurative lesions were surgically proved with marked relief of pain after surgery. In the other patients the final diagnoses were 37 cases of levator ani syndrome (36%) and 26 cases of unspecified functional anorectal pain (25%). No MRI abnormalities were found in 33 of the patients with levator ani syndrome and 26 of the patients with unspecified anorectal pain. The two readers had very good agreement (κ = 0.92). The patients with a history of anorectal disease had significantly more MRI findings of abnormalities (60%) than did patients without a history of anorectal disease (23%). The positive predictive value of MRI was 91%, and the negative predictive value was 100%. CONCLUSION: In 39% of patients, MRI showed abnormalities that were clinically confirmed as the final diagnosis. Surgical treatment will especially benefit patients with suppurative lesions, resulting in relief of pain.

Prediction of tumor stage and lymph node involvement with dynamic contrast-enhanced MRI after chemoradiotherapy for locally advanced rectal cancer.

PURPOSE: The usefulness of restaging by magnetic resonance imaging (MRI) after chemoradiotherapy (CTx/RTx) in patients with locally advanced rectal cancer has not yet been established, mostly due to the difficult differentiation between viable tumor and fibrosis. MRI with dynamic contrast-enhanced (DCE) sequences may be of additional value in distinguishing malignant from nonmalignant tissue. The aim of this study was to assess the accuracy of tumor, nodal staging, and circumferential resection margin (CRM) involvement by MRI with DCE sequences after CTx/RTx. METHODS: The accuracies were assessed by MRI on T2-weighted magnetic resonance (MR) images with DCE sequences in patients with locally advanced rectal cancer after a long course of CTx/RTx. MR images were assessed by two independent radiologists. RESULTS: For tumor staging and CRM involvement, MRI with DCE sequences had an accuracy of 45 and 60 %, respectively. The accuracy for nodal staging was 93 %. On MRI, malignant lymph nodes had a median diameter of 8 mm (range, 4-18) and benign lymph nodes a median diameter of 4 mm (range, 3-11). A significant indicator for benign nodes was hypointensity on T2-weighted images (p < 0.001) and early complete arterial phase enhancement on DCE-weighted images (p < 0.001). A significant indicator for malignant nodes was heterogeneity on T2-weighted images (χ (2), p < 0.000) and early incomplete arterial phase enhancement on DCE (p < 0.001). CONCLUSIONS: MRI with DCE is a useful tool for nodal staging after CTx/RTx. The addition of DCE sequences did not improve the accuracy of determining the tumor stage, CRM involvement, and in detecting complete response.