Clinical added value of MRI to CT in patients scheduled for local therapy of colorectal liver metastases (CAMINO): study protocol for an international multicentre prospective diagnostic accuracy study.

BACKGROUND: Abdominal computed tomography (CT) is the standard imaging method for patients with suspected colorectal liver metastases (CRLM) in the diagnostic workup for surgery or thermal ablation. Diffusion-weighted and gadoxetic-acid-enhanced magnetic resonance imaging (MRI) of the liver is increasingly used to improve the detection rate and characterization of liver lesions. MRI is superior in detection and characterization of CRLM as compared to CT. However, it is unknown how MRI actually impacts patient management. The primary aim of the CAMINO study is to evaluate whether MRI has sufficient clinical added value to be routinely added to CT in the staging of CRLM. The secondary objective is to identify subgroups who benefit the most from additional MRI. METHODS: In this international multicentre prospective incremental diagnostic accuracy study, 298 patients with primary or recurrent CRLM scheduled for curative liver resection or thermal ablation based on CT staging will be enrolled from 17 centres across the Netherlands, Belgium, Norway, and Italy. All study participants will undergo CT and diffusion-weighted and gadoxetic-acid enhanced MRI prior to local therapy. The local multidisciplinary team will provide two local therapy plans: first, based on CT-staging and second, based on both CT and MRI. The primary outcome measure is the proportion of clinically significant CRLM (CS-CRLM) detected by MRI not visible on CT. CS-CRLM are defined as liver lesions leading to a change in local therapeutical management. If MRI detects new CRLM in segments which would have been resected in the original operative plan, these are not considered CS-CRLM. It is hypothesized that MRI will lead to the detection of CS-CRLM in ≥10% of patients which is considered the minimal clinically important difference. Furthermore, a prediction model will be developed using multivariable logistic regression modelling to evaluate the predictive value of patient, tumor and procedural variables on finding CS-CRLM on MRI. DISCUSSION: The CAMINO study will clarify the clinical added value of MRI to CT in patients with CRLM scheduled for local therapy. This study will provide the evidence required for the implementation of additional MRI in the routine work-up of patients with primary and recurrent CRLM for local therapy. TRIAL REGISTRATION: The CAMINO study was registered in the Netherlands National Trial Register under number NL8039 on September 20th 2019.

Reasons for (non)participation in supplemental population-based MRI breast screening for women with extremely dense breasts.

AIM: To determine the willingness of women with extremely dense breasts to undergo breast cancer screening with magnetic resonance imaging (MRI) in a research setting, and to examine reasons for women to participate or not. MATERIALS AND METHODS: Between 2011 and 2015, 8,061 women (50-75 years) were invited for supplemental MRI as part of the Dense Tissue and Early Breast Neoplasm Screening (DENSE) trial (ClinicalTrials.gov Identifier: NCT01315015), after a negative screening mammography in the national population-based mammography screening programme. Demographics of participants and non-participants were compared. All invitees were asked to report reasons for (non)participation. Ethical approval was obtained. Participants provided written informed consent. RESULTS: Of the 8,061 invitees, 66% answered that they were interested, and 59% eventually participated. Participants were on average 54-years old (interquartile range: 51-59 years), comparable to women with extremely dense breasts in the population-based screening programme (55 years). Women with higher socio-economic status (SES) were more often interested in participation than women with lower SES (68% versus 59%, p<0.001). The most frequently stated reasons for non-participation were "MRI-related inconveniences and/or self-reported contraindications to MRI" (27%) and "anxiety regarding the result of supplemental screening" (21%). "Expected personal health benefit" (68%) and "contribution to science" (43%) were the most frequent reasons for participation. CONCLUSION: Of women invited for MRI because of extremely dense breasts, 59% participated. Common reasons for non-participation were "MRI-related inconveniences" and "anxiety regarding the result of supplemental screening". In case of future implementation, availability of precise evidence on benefits and harms might reduce this anxiety.

Magnetic resonance imaging in patients with unilateral bloody nipple discharge; useful when conventional diagnostics are negative?

BACKGROUND: Unilateral bloody nipple discharge (UBND) is mostly caused by benign conditions such as papilloma or ductal ectasia. However, in 7-33 % of all nipple discharge, it is caused by breast cancer. Conventional diagnostic imaging like mammography (MMG) and ultrasonography (US) is performed to exclude malignancy. Preliminary investigations of breast magnetic resonance imaging (MRI) assume that it has additional value. With an increasing availability of MRI, it is of clinical importance to evaluate this. We evaluated the additional diagnostic value of MRI in patients with UBND in the absence of a palpable mass, with normal conventional imaging. METHODS: All women with UBND in the period November 2007-July 2012 were included. In addition to the standard work-up (patient's history, physical examination, MMG, and US), MRI was performed. Data from these examinations and treatment were collected retrospectively. RESULTS: A total of 111 women (mean age 52 years; range 23-80) were included. In nine (8 %) patients, malignancy was suspected on MRI while conventional imaging was normal. In eight (89 %) of these patients, histology was obtained, two by core biopsy and six by terminal duct excision. Benign conditions were found in six patients (86 %) and a (pre-) malignant lesion in two patients. In both cases, it concerned a ductal carcinoma in situ, which was treated with breast-conserving therapy. Moreover, in two cases of (pre)malignancy, the MRI was interpreted as negative. CONCLUSION: In patients with UBND who show no signs of a malignancy on conventional diagnostic examinations, the added value of a breast MRI is limited, since a malignancy can be demonstrated in <2 %.

A fetal circle of Willis is associated with a decreased deep white matter lesion load.

OBJECTIVE: To investigate the relationship between morphologic differences in the circle of Willis and the presence and location of white matter lesions (WMLs). METHODS: Two hundred forty-three consecutive patients with clinical manifestations of atherosclerotic disease underwent MRI of the brain and MR angiography of the circle of Willis. RESULTS: Subjects with a fetal configuration of the circle of Willis demonstrated a decreased load of small (p < 0.01) and medium (p < 0.01) deep WMLs compared with subjects with a nonfetal configuration of the posterior part of the circle of Willis. CONCLUSION: A fetal configuration of the posterior part of the circle of Willis may be an important protecting determinant in the etiology of white matter lesions.

High total cerebral blood flow is associated with a decrease of white matter lesions.

BACKGROUND: Low cerebral blood flow (CBF) has been associated with the presence of white matter lesions (WMLs). However, the power of these studies was insufficient (n=20-35) to determine whether flow is associated with WMLs. PURPOSE: The aim of this study was to investigate whether total cerebral blood flow (tCBF) is associated with the severity of white matter lesions (WMLs) in a large patient sample. SUBJECTS AND METHODS: 228 patients with clinical symptoms of cardiovascular disease had MRI of the brain, consisting of a T2-w FLAIR and a 2D phase-contrast flow measurement of the internal carotid arteries and the basilar artery. WMLs were graded according to prevalence and size of deep and periventricular WMLs. To determine the relation between tCBF and WMLs we used linear and logistic regression analysis adjusted for age, gender, intima media thickness and hypertension. RESULTS: We observed an inverse association between the tCBF and the total number of WMLs adjusted for age, gender, intima media thickness and hypertension [B=-1, 0 WML 95% CI (-2.0 to 0.0, p=0.045) per 100 mL increase in tCBF]. The adjusted odds ratio for the presence of severe WMLs in patients with high tCBF (> 675 mL/min) was 0.5 (95% CI 0.2-1.0) compared with patients with normal tCBF. CONCLUSION: In this study we found that high tCBF is associated with a decrease in presence and severity of WMLs.

Collateral flow and ischemic brain lesions in patients with unilateral carotid artery occlusion.

OBJECTIVE: To investigate the association between ischemic brain lesions and intracranial collateral blood flow in patients with unilateral occlusion of the internal carotid artery (ICA). METHODS: Sixty-eight consecutive patients were included. Ischemic lesions on MRI were identified on hard copies, and volume measurements of the lesions were performed on an MR workstation. Intracranial collateral pathways were studied with MR angiography, digital subtraction angiography, and transcranial Doppler sonography. RESULTS: The presence of collateral flow via the anterior communicating artery (ACoA) was associated with a reduction in prevalence (p = 0.01) and volume (p = 0.008) of internal border zone infarcts in the hemisphere ipsilateral to the occluded ICA. Absence of collateral blood flow via the circle of Willis was associated with an increase in prevalence (p = 0.007) and volume (p = 0.005) of internal border zone infarcts. No association between any collateral flow pattern in the circle of Willis and periventricular lesions or lacunar, territorial, or external border zone infarcts was found. No association between collateral flow via the ophthalmic artery or leptomeningeal vessels with any type of ischemic lesion was found. CONCLUSION: Collateral flow via the ACoA is associated with a reduction of the prevalence and volume of internal border zone lesions but not with any other type of ischemic lesion. The presence of a functional posterior communicating artery or secondary collateral pathways is not associated with the prevalence of any type of ischemic lesion.