Correction to. Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting

Objectives: To update the 2012 ESGAR consensus guidelines on the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. Methods Fourteen abdominal imaging experts from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) participated in a consensus meeting, organised according to an adaptation of the RAND-UCLA Appropriateness Method. Two independent (non-voting) Chairs facilitated the meeting. 246 items were scored (comprising 229 items from the previous 2012 consensus and 17 additional items) and classified as ‘appropriate’ or ‘inappropriate’ (defined by ≥ 80 % consensus) or uncertain (defined by < 80 % consensus). Results: Consensus was reached for 226 (92 %) of items. From these recommendations regarding hardware, patient preparation, imaging sequences and acquisition, criteria for MR imaging evaluation and reporting structure were constructed. The main additions to the 2012 consensus include recommendations regarding use of diffusion-weighted imaging, criteria for nodal staging and a recommended structured report template. Conclusions: These updated expert consensus recommendations should be used as clinical guidelines for primary staging and restaging of rectal cancer using MRI

Magnetic resonance imaging of rectum : Diagnostic and therapy related aspects

Papers I-II: The purpose of paper 1 was to assess the size and configuration of the perirectal fatty tissues (PF) using magnetic resonance imaging (MRI). In 25 subjects the volume and cross-sectional parameters based on the amount of PF to different sides of die rectum, and the total area occupied were retrospectively measured on MRI. There was a good correlation between anteroposterior diameter of the PF at four centimeter below S 1-2 (and the left-to-right diameter seven centimeter below S 1-2), and mesorectal volume (NW). Furthermore, the form of PF differed significantly between male and female subjects. In paper II, we analyzed the influence of MV on the accuracy of the first preoperative MRI. 267 patients with rectal cancer had their MV measured without knowledge of the prospective evaluations by the radiologist or the pathologist, and the discrepancies in the results were correlated to the MV and clinical data. T- or N-staging accuracy by MRI did not significantly correlate to MV. The difference between assessment by radiologist and pathologist did not differ based on MV. Finally patients with larger MV did not have fewer cases with involvement of mesorectal fascia (MF) or involvement of neighboring organs. Thus, MV does not appear to affect the locoregional prognostic factors, nor is it able to explain the difference in evaluation between the radiologist and pathologist. Papers II-IV: In paper III we tried to find out if the tumor size on MRI in patients without preoperative radiotherapy correlates to the corresponding pathologic findings. 18 patients were included. The tumor size was measured on MR and histopathologic specimen. Regression curves showed best correlations for area (r2=0.75) and volume (r2=0.65-0.82). With the formula proposed from this material, we assume that rectal tumors can be measured on MR images using a metric model, and then extrapolated to what we would expect from pathology, hence providing us with a tool where we could measure tumor response after neoadjuvant therapy. In paper IV, we used these tools to evaluate changes after radiotherapy and correlation between MRI and histopathology. RVs was defined as the residual pathologic tumor volume while RVm was similarly defined as the residual MRI tumor volume at 2 nd MRI. 25 patients with MRI before and after radiotherapy were included. The second MRI was not more accurate than the initial MRI for assessment of the T-stage or distance to circumferential resection margin (CRM). RVm showed significant correlation to RVs and pathologic T-stage. A 2 nd MRI alone after radiotherapy with delay before surgery has limited value in understanding the individual response to therapy, but followup volumetry can be helpful to understand which tumors have responded. Paper V: The aim of this study was to determine the sites of local recurrence (LR) following radical total mesorectal excision (TME) for rectal cancer in an effort to elucidate the reasons for recurrence. 33 CT and MRI of 37 patients with LR were examined. 29 LR were found in the lower two-thirds of the pelvis, with two appearing to originate from lateral pelvic lymph nodes (LN). Evidence of residual PF was identified in 15 patients. 14 of the LR originated from primary tumors in the upper rectum and 12 of them with evidence of residual PF. Lateral pelvic LN metastases are not a major cause of LR after TME. Partial mesorectal excision may be associated with an increased risk of LR from tumors in the upper rectum

Stereology: a novel technique for rapid assessment of liver volume

Abstract Background The purpose of this study was to test the stereology method using several grid sizes for measuring liver volume and to find which grid provides an accurate estimate of liver volume. Materials and methods Liver volume was measured by volumetry in 41 sets of liver MRI. MRI was performed before and after different weight-reducing regimens. Grids of 3, 4, 5, and 6 cm were used to measure liver volume on different occasions by stereology. The liver volume and the changes in volume before and after treatment were compared between stereology and volumetry. Results There was no significant difference in measurements between stereology methods and volumetry (p > 0.05). The mean differences in liver volume between stereology based on 3-, 4-, 5-, and 6-cm grids and volumetry were 37, 3, 132, and 23 mL, respectively, and the differences in measurement of liver volume change were 21, 2, 19, and 76 mL, respectively. The mean time required for measurement by stereology was 59–190 s. Conclusion Stereology employing 3- and 4-cm grids can rapidly provide accurate results for measuring liver volume and changes in liver volume. Main Messages • Statistical methods can be used for measuring area/volume in radiology. • Measuring liver volume by stereology by 4-cm grids can be done in less than two minutes. • Follow-up of liver volume is highly accurate with stereological methods

Pulmonary influences on early post-operative recovery in patients after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy treatment : a retrospective study

Background: The combination of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a curative treatment option for peritoneal carcinomatosis (PC). There have been few studies on the pulmonary adverse events (AEs) affecting patient recovery after this treatment, thus this study investigated these factors. Methods: Between January 2005 and December 2006, clinical data on all pulmonary AEs and the recovery progress were reviewed for 76 patients with after CRS and HIPEC. Patients with pulmonary interventions (thoracocenthesis and chest tubes) were compared with the non-intervention patients. Two senior radiologists, blinded to the post-operative clinical course, separately graded the occurrence of pulmonary AEs. Results: Of the 76 patients, 6 had needed thoracocentesis and another 6 needed chest tubes. There were no differences in post-operative recovery between the intervention and non-intervention groups. The total number of days on mechanical ventilation, the length of stay in the intensive care unit, total length of hospital stay, tumor burden, and an American Society of Anesthesiologists (ASA) grade of greater than 2 were correlated with the occurrence of atelectasis and pleural effusion. Extensive atelectasis (grade 3 or higher) was seen in six patients, major pleural effusion (grade 3) in seven patients, and signs of heart failure (grade 1-2) in nine patients. Conclusions: Clinical and radiological post-operative pulmonary AEs are common after CRS and HIPEC. However, most of the pulmonary AEs did not affect post-operative recovery

Diagnostic Accuracy of Acute Diverticulitis with Non-Enhanced Low-Dose CT

Purpose: To evaluate the diagnostic accuracy of non-enhanced low-dose computed tomography (LDCT) in acute colonic diverticulitis with contrast-enhanced standard-dose CT (SDCT) as the reference method. Materials and Methods: Consecutive patients with clinically suspected diverticulitis were included from two hospitals between January and October 2017. All patients underwent LDCT followed by SDCT. All CT examinations were assessed for signs of diverticulitis, complications, and other diagnoses by three independent radiologists (two radiology consultants and one fourth-year resident) using SDCT as the reference method. Sensitivity, specificity, and agreement were calculated. Results: In total, 149 patients (median age 68, 107 women) were included; 107 had diverticulitis on standard CT. Sensitivity for diverticulitis using LDCT was 100%; the values were 99% for consulting radiologists and 92% for the radiology resident. Specificity was 100% for both consultants and 84% for the resident. Sensitivity for identification of complications was 74%, 60%, and 54%, respectively. Twenty-six patients had other causes of abdominal symptoms on standard CT, 23 (88%) of whom were diagnosed correctly on LDCT. One case of splenic infarction and two cases of segment colitis were missed on LDCT. Conclusion: The diagnostic accuracy of LDCT was high for acute diverticulitis. Therefore, it is recommended as a standard method that should help to reduce radiation dose and cost. LDCT had lower sensitivity for complications, although discrimination between an inflamed diverticulum and small pericolic abscess accounted for a proportion of the discrepancies

Magnetic Resonance Imaging of Rectal and Anal Cancer

Magnetic resonance imaging plays a pivotal role in the imaging and staging of rectal and anal carcinomas. Rectal adenocarcinomas and anal squamous cell carcinomas behave differently, and are staged and treated differently. This article attempts to explain these 2 entities, which share the same regions of interest, in a comprehensive manner

The importance of rectal cancer MRI protocols on iInterpretation accuracy

Abstract Background Magnetic resonance imaging (MRI) is used for preoperative local staging in patients with rectal cancer. Our aim was to retrospectively study the effects of the imaging protocol on the staging accuracy. Patients and methods MR-examinations of 37 patients with locally advanced disease were divided into two groups; compliant and noncompliant, based on the imaging protocol, without knowledge of the histopathological results. A compliant rectal cancer imaging protocol was defined as including T2-weighted imaging in the sagittal and axial planes with supplementary coronal in low rectal tumors, alongside a high-resolution plane perpendicular to the rectum at the level of the primary tumor. Protocols not complying with these criteria were defined as noncompliant. Histopathological results were used as gold standard. Results Compliant rectal imaging protocols showed significantly better correlation with histopathological results regarding assessment of anterior organ involvement (sensitivity and specificity rates in compliant group were 86% and 94%, respectively vs. 50% and 33% in the noncompliant group). Compliant imaging protocols also used statistically significantly smaller voxel sizes and fewer number of MR sequences than the noncompliant protocols Conclusion Appropriate MR imaging protocols enable more accurate local staging of locally advanced rectal tumors with less number of sequences and without intravenous gadolinium contrast agents.</p