R.G.H. Beets-Tan

Accuracy of magnetic resonance imaging in prediction of tumour-free resection margin in rectal cancer surgery

BACKGROUND Incomplete surgical removal of the circumferential tumour spread is believed to be the main cause of local recurrence after resection of rectal cancer. This study assessed the accuracy of magnetic resonance imaging (MRI) with a phased-array coil for preoperative staging and prediction of the distance of the tumour from the circumferential resection margin in a total mesorectal excision. METHODS 76 patients with primary rectal cancer were preoperatively assessed by MRI at 1.5 T, with a phased-array coil. Two observers independently scored, on two occasions, the tumour stage and measured the distance to the mesorectal fascia. Their findings were compared with the final histological findings. FINDINGS The MRI tumour stage agreed with the histological stage in 63 (83%) of 76 patients (weighted kappa=0.77 [95% CI 0.66-0.89]) for observer 1, and in 51 (67%) patients (weighted kappa=0.52 [0.37-0.67]) for observer 2. The intraobserver agreement on the tumour stage was good (kappa=0.80 [0.69-0.91]) for observer 1 but moderate (kappa=0.49 [0.34-0.65]) for observer 2. The interobserver agreement was moderate (kappa=0.53 [0.38-0.69]). In 12 patients with an obvious T4 tumour, a margin of 0 mm was correctly predicted. Of 29 patients for whom the pathologist reported a distance of at least 10 mm without specifying the actual distance, a distance of at least 10 mm was predicted in 28 by observer 1 and 27 by observer 2. For the remaining 35 patients, a regression curve was constructed; from this, a histological distance of at least 1.0 mm can be predicted with high confidence when the measured distance on MRI is at least 5.0 mm. INTERPRETATION MRI with a phased-array coil showed moderate accuracy and reproducibility for predicting the tumour stage of rectal cancers. The clinically more important circumferential resection margin can, however, be predicted with high accuracy and consistency, allowing preoperative identification of patients at risk of recurrence who will benefit from preoperative radiotherapy, more extensive surgery, or both.

Detection of lymph node metastases in head and neck cancer: a meta-analysis comparing US, USgFNAC, CT, and MR imaging

Purpose: To perform a meta-analysis comparing ultrasonography (US), US guided fine needle aspiration cytology (USgFNAC), computed tomography (CT), and magnetic resonance imaging (MRI) in the detection of lymph node metastases in head and neck cancer. Methods: MEDLINE, EMBASE and Cochrane databases were searched (January 1990–January 2006) for studies reporting diagnostic performances of US, USgFNAC, CT, and MRI to detect cervical lymph node metastases. Two reviewers screened text and reference lists of potentially eligible articles. Criteria for study inclusion: (1) histopathology was the reference standard, (2) primary tumors and metastases were squamous cell carcinoma and (3) data were available to construct 2 × 2 contingency tables. Meta-analysis of pairs of sensitivity and specificity was performed using bivariate analysis. Summary estimates for diagnostic performance used were sensitivity, specificity, diagnostic odds ratios (DOR) (95% confidence intervals) and summary receiver operating characteristics (SROC) curves. Results: From seventeen articles, 25 data sets could be retrieved. Eleven articles studied one modality: US (n = 4); USgFNAC (n = 1); CT (n = 3); MRI (n = 3). Six articles studied two or more modalities: US and CT (n = 2); USgFNAC and CT (n = 1); CT and MRI (n = 1); MRI and MRI-USPIO (Sinerem ® )( n = 2); US, USgFNAC, CT and MRI (n = 1). USgFNAC (AUC = 0.98) and US (AUC = 0.95) showed the highest areas under the curve (AUC). MRI-USPIO (AUC = 0.89) and CT (AUC = 0.88) had similar results. MRI showed an AUC = 0.79. USgFNAC showed the highest DOR (DOR = 260) compared to US (DOR = 40), MRI-USPIO (DOR = 21), CT (DOR = 14) and MRI (DOR = 7). Conclusion USgFNAC showed to be the most accurate imaging modality to detect cervical lymph node metastases.

High-resolution magnetic resonance imaging of the anorectal region without an endocoil

AbstractBackground: To evaluate the feasibility of a high-resolution magnetic resonance imaging (MRI) technique in detailed imaging of the anal sphincter and lower pelvic region without the use of an endoluminal coil. Methods: MRIs with an external phased array coil (T1- and T2-weighted turbo spin echo) were performed in 22 volunteers and 12 patients with an anal fistula, an anal sphincter defect, or a rectal tumor. The normal scans were evaluated by three independent observers. The scans of the patients were compared with surgical and/or histologic findings. Results: The anal sphincter was visualized with detail. In the anal canal, hemorrhoidal tissue and the submucosae ani muscle could be seen. The MRI technique also allowed detailed imaging of anatomical structures above the pelvic floor. The MR findings in the 12 patients showed exact correlation with surgery and/or histology. Conclusions: High-resolution MRI of the anorectal region without an endoluminal coil is feasible. The MR technique with an external phased array coil allows detailed imaging of the anal sphincter at rest, the rectum, and the surrounding pelvic structures with one single investigation. The results are promising and suggest useful applications in the management of anorectal diseases.

Morphological MRI criteria improve the detection of lymph node metastases in head and neck squamous cell carcinoma: multivariate logistic regression analysis of MRI features of cervical lymph nodes

The aim was to evaluate whether morphological criteria in addition to the size criterion results in better diagnostic performance of MRI for the detection of cervical lymph node metastases in patients with head and neck squamous cell carcinoma (HNSCC). Two radiologists evaluated 44 consecutive patients in which lymph node characteristics were assessed with histopathological correlation as gold standard. Assessed criteria were the short axial diameter and morphological criteria such as border irregularity and homogeneity of signal intensity on T2-weighted and contrast-enhanced T1-weighted images. Multivariate logistic regression analysis was performed: diagnostic odds ratios (DOR) with 95% confidence intervals (95% CI) and areas under the curve (AUCs) of receiver-operating characteristic (ROC) curves were determined. Border irregularity and heterogeneity of signal intensity on T2-weighted images showed significantly increased DORs. AUCs increased from 0.67 (95% CI: 0.61–0.73) using size only to 0.81 (95% CI: 0.75–0.87) using all four criteria for observer 1 and from 0.68 (95% CI: 0.62–0.74) to 0.96 (95% CI: 0.94–0.98) for observer 2 (p < 0.001). This study demonstrated that the morphological criteria border irregularity and heterogeneity of signal intensity on T2-weighted images in addition to size significantly improved the detection of cervical lymph nodes metastases.

Levator hiatal area as a risk factor for cystocele recurrence after surgery: a prospective study

To investigate whether increased levator hiatal area, measured preoperatively, was independently associated with anatom‐ical cystocele recurrence 12 months after anterior colporrhaphy.

High resolution MRI of anorectal malformation in the newborn: case reports of Currarino syndrome and anocutaneous fistula

To show the accuracy of a high-resolution magnetic resonance imaging (MRI) technique with a phased array coil in diagnosing anorectal malformation, we present two neonates with Currarino syndrome and anocutaneous fistula, respectively. Anatomy was visualized correctly with this technique, but conventional MRI did not show the complete extent of the disease. The reported high-resolution MRI findings concerning these conditions are scanty.

Comparison of translabial three-dimensional ultrasound with magnetic resonance imaging for measurement of levator hiatal biometry at rest

To compare translabial three‐dimensional (3D) ultrasound with magnetic resonance imaging (MRI) for the measurement of levator hiatal biometry at rest in women with pelvic organ prolapse, and to determine the interobserver reliability between two independent observers for ultrasound and MRI measurements.

Achievements in colorectal cancer care during 8 years of auditing in The Netherlands

INTRODUCTION The efficacy of auditing is still a subject of debate and concerns exist whether auditing promotes risk averse behaviour of physicians. This study evaluates the achievements made in colorectal cancer surgery since the start of a national clinical audit and assesses potential signs of risk averse behaviour. METHODS Data were extracted from the Dutch ColoRectal Audit (2009-2016). Trends in outcomes were evaluated by uni and multivariable analyses. Patients were stratified according to operative risks and changes in outcomes were expressed as absolute (ARR) and relative risk reduction (RRR). To assess signs of risk averse behaviour, trends in stoma construction in rectal cancer were analysed. RESULTS Postoperative mortality decreased from 3.4% to 1.8% in colon cancer and from 2.3% to 1% in rectal cancer. Surgical and non-surgical complications increased, but with less reintervention. For colon cancer, the high-risk elderly patients had the largest ARR for complicated postoperative course (6.4%) and mortality (5.9%). The proportion of patients receiving a diverting stoma or end colostomy after a (L)AR decreased 11% and 7%, respectively. In low rectal cancer, patients increasingly received a non-diverted primary anastomosis (5.4% in 2011 and 14.4% in 2016). CONCLUSIONS No signs of risk averse behaviour was found since the start of the audit. Especially the high-risk elderly patients seem to have benefitted from improvements made in colon cancer treatment in the past 8 years. For rectal cancer, trends towards the construction of more primary anastomoses are seen. Future quality improvement measures should focus on reducing surgical and non-surgical complications.

Comparison of translabial three-dimensional ultrasound with magnetic resonance imaging for measurement of levator hiatal biometry at rest: Levator hiatus biometry on ultrasound and MRI

To compare translabial three‐dimensional (3D) ultrasound with magnetic resonance imaging (MRI) for the measurement of levator hiatal biometry at rest in women with pelvic organ prolapse, and to determine the interobserver reliability between two independent observers for ultrasound and MRI measurements.