Human papillomavirus does not play a role in the Barrett esophagus: a French cohort.

The role of human papillomavirus (HPV) in Barrett's esophagus (BE) has been examined but remains unclear. The purpose of the study is to dispute the connection between HPV and BE in a prospective case-control study. Biopsies were performed above and inside the Barrett's segment for BE patients and in the distal third of the esophagus for control patients for histological interpretation and for virological analysis. Biopsies for virological analysis were placed in a virus transport medium and immediately frozen in liquid nitrogen. Virological analysis involved real-time PCR using the SyBr® green protocol with modified SPF10 general primers. A total of 180 patients (119 control and 61 BE, respectively) were included. In BE patients, 31, 18, and 12 patients had, respectively, no dysplasia, low-grade dysplasia, and high grade dysplasia. Overall, nine were found to be HPV positive: five were control patients and four BE patients. HPV positive status was not associated with BE. No factors were associated with HPV, in particular the degree of BE dysplasia. HPV infection appears unlikely to be significant in the etiology of BE compared with control patients. (ClinicalTrials.gov, Number NCT02549053).

Accuracy of computed tomographic colonography in a nationwide multicentre trial, and its relation to radiologist expertise.

OBJECTIVE: Reports on the accuracy of computed tomographic colonography (CTC) mainly involve series from expert institutions. The aims of this study were to assess CTC accuracy in a nationwide population and to relate it to radiologist performance in their initial training. DESIGN: Nationwide multicentre trial. SETTING: Twenty-eight radiologists, working in 26 mostly academic clinical units, were involved in the study after having attended a formal specialised 2-day training session on CTC. They worked through a training set of 52 cases with automatic feedback after an attempt at each case. PATIENTS: The study enrolled 845 patients with average and high risk of colorectal cancer, 737 of whom had both complete CTC and videocolonoscopy data, which constituted the dataset. INTERVENTIONS: Patients underwent same-day CTC followed by videocolonoscopy with segmental unblinding of CTC results. MAIN OUTCOME MEASURES: Sensitivity, specificity and positive and negative predictive values for detection of polyps ≥ 6 mm in per-patient and per-lesion analyses of CTC without computer-aided detection. RESULTS: Sensitivity, specificity and positive and negative predictive values for patients with polyps ≥ 6 mm were 69% (95% CI 61% to 77%), 91% (95% CI 89% to 94%), 67% (95% CI 59% to 74%) and 92% (95% CI 90% to 94%), respectively. Univariate analysis showed that the detection rate for polyps ≥ 6 mm was linked to neither radiologist case volume nor number of polyps, but was related to sensitivity achieved in the training set. Pooled sensitivity was 72% (95% CI 63% to 80%) versus 51% (95% CI 40% to 60%) for radiologists achieving above and below median sensitivity in the training set (61%), respectively. Multivariate analysis showed that sensitivity for polyps ≥ 6 mm in the training set was the only remaining significant predictive factor for subsequent performance. CONCLUSIONS: Radiologist sensitivity CTC for detection of polyps ≥ 6 mm in training was the sole independent predictor for subsequent sensitivity in detection of such polyps.

[MR-endoscopic US correlation for loco-regional staging of rectal carcinoma]. / Corrélation IRM-échoendoscopie dans le bilan d'extension locorégional initial du cancer du rectum.

INTRODUCTION: To correlate findings at high-resolution MR and endoscopic US (EUS) for preoperative loco-regional staging of rectal carcinoma. PATIENTS AND METHODS: Fifty-two patients with rectal carcinoma underwent high-resolution MR imaging. Only 43 of these patients underwent EUS due to technical limitations and stenosing carcinomas. Morphological imaging features and TNM staging were evaluated for both imaging modalities. The degree of correlation and accuracy were calculated for both. RESULTS: The correlation between MR and EUS was good for tumor length and thickness (r=0.7 and 0.61) for for nodal (N) staging (k=0.53). Correlation was good for T1 and T2 stages (k=0.51) and T3 stage (k=0.43) and very poor for stage 4 (k= -0.09), because no T4 lesion was detected at EUS. 81.8% of patients where T stage was over-estimated on MRI and 100% of patients where T stage was over-estimated on EUS had received preoperative radiation therapy. Therefore, results should be interpreted with caution. The predictive evaluation of tumor resectability (absence of perirectal fascia invasion) with a circumferential margin on MR> or =5 mm was 93%. CONCLUSION: Correlation between MR and EUS was moderate for T staging, because of limitations of EUS for large tumors. Results confirm that high-resolution MRI is useful for loco-regional staging of rectal carcinoma, especially for large tumors. EUS should be limited to the valuation of superficial tumors of the rectum.

Combined use of T1-weighted MRI and MRA for stereotaxic lesioning of the nonhuman primate brain: application to the rhinal cortex.

Stereotaxic brain lesioning is widely used to develop experimental models of human brain disease in the nonhuman primate. To avoid intraoperative vascular complications such as intracranial hemorrhage, we developed a methodology that is easy to implement. This method combines T1-weighted magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). This technique is applied to produce bilateral neurotoxic lesions of the rhinal cortex, a structure located medially in the temporal lobe, in eight baboons (including five sham-operated animals with needle descents but no ibotenic acid injection). Two other baboons were lesioned before the MRA technology was available. The MRA sequence (two-dimensional time-of-flight, axial acquisition) was used to localize the blood vessels in the needle trajectories, i.e., the highly vascularized sylvian fissure and temporal gyri. The vessel coordinates were transposed onto the coronal MRI-TI images, onto which the injection sites were determined and the planned needle tracks drawn. In the eight baboons that had MRA, 26.8% of these needle tracks had to be slightly displaced because of the presence of blood vessels. The stereotaxic coordinates of the final target sites were then calculated with respect to six skull landmarks that also served as a reference during surgery. No intracranial hemorrhage occurred in any of the eight baboons in which MRA was performed, in contrast to one of the two baboons not studied with MRA. The histological analysis showed a good extent of the rhinal lesions in all lesioned animals, with minimal damage to areas other than those that were targeted. Thus, combined use of MRI-TI and MRA proved to be reliable in reducing vascular complications, affording new advances for stereotaxic surgery in nonhuman primates.

Contralateral cerebellar hypometabolism: a predictor for stroke outcome?

Contralateral cerebellar hypometabolism (CCH) is a well established remote functional effect of cerebral damage. Because CCH has been reported to be reversible in acute stroke in at least some patients, the value of cerebellar metabolic asymmetry (CbMA; a reflection of the degree of CCH) as a predictor of stroke outcome has been assessed. Measurements of cerebellar oxygen consumption were performed by positron emission tomography (PET) in 16 patients within 5-30 hours of onset of their first ever middle cerebral artery territory stroke, and again 13-56 days later in 12 survivors. The neurological state was quantified at the time of each PET study and at day 60, with both the Mathew and Orgogozo scales. In the early PET study, the CbMAs ranged from around 0% to nearly 50% (individually significant at p < 0.05 in 9/16 patients) but were neither strongly nor consistently correlated with neurological outcome or recovery at day 60. Similarly, the changes in CbMAs from the early to the late PET study were not correlated with the concomitant neurological evolution. At the late PET study, however, there were excellent positive correlations between CbMAs and both neurological status and size of infarction (assessed by CT in the chronic stage). The correlation with neurological status was explained by the correlation with size of infarction. The poor predictive value of CbMAs in the early PET study may be partly because the cerebral metabolic disturbance might still be evolving at this early stage in some cases. Despite this lack of a strong quantitative link between CbMAs at the early PET study and outcome, the outcome was good in all the patients who did not exhibit significant CCH, suggesting that lack of CCH may predict good outcome in acute middle cerebral artery stroke.