Cost-effectiveness of pancreas surveillance: The CDKN2A-p16-Leiden cohort.

BACKGROUND: CDKN2A-p16-Leiden mutation carriers have a high lifetime risk of developing pancreatic ductal adenocarcinoma (PDAC), with very poor survival. Surveillance may improve prognosis. OBJECTIVE: To assess the cost-effectiveness of surveillance, as compared to no surveillance. METHODS: In 2000, a surveillance program was initiated at Leiden University Medical Center with annual MRI and optional endoscopic ultrasound. Data were collected on the resection rate of screen-detected tumors and on survival. The Kaplan-Meier method and a parametric cure model were used to analyze and compare survival. Based on the surveillance and survival data from the screening program, a state-transition model was constructed to estimate lifelong outcomes. RESULTS: A total of 347 mutation carriers participated in the surveillance program. PDAC was detected in 31 patients (8.9%) and the tumor could be resected in 22 patients (71.0%). Long-term cure among patients with resected PDAC was estimated at 47.1% (p < 0.001). The surveillance program was estimated to reduce mortality from PDAC by 12.1% and increase average life expectancy by 2.10 years. Lifelong costs increased by €13,900 per patient, with a cost-utility ratio of €14,000 per quality-adjusted life year gained. For annual surveillance to have an acceptable cost-effectiveness in other settings, lifetime PDAC risk needs to be 10% or higher. CONCLUSION: The tumor could be resected in most patients with a screen-detected PDAC. These patients had considerably better survival and as a result annual surveillance was found to be cost-effective.

Value of Magnetic Resonance Cholangiopancreatography in Assessment of Nonanastomotic Biliary Strictures After Liver Transplantation.

UNLABELLED: Nonanastomotic biliary strictures (NAS) remain a frequent complication after orthotopic liver transplantation (OLT). The aim of this study was to evaluate whether magnetic resonance cholangiopancreatography (MRCP) could be used to detect NAS and to grade the severity of biliary strictures. METHODS: In total, 58 patients after OLT from 2 Dutch transplantation centers in whom endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography and MRCP were performed within less than 6 months apart were included in the study. Of these patients, 41 had NAS and 17 were without NAS based on endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography and follow-up. Four radiologists-2 from each center-used an adapted validated classification-termed "Leiden Biliary Stricture Classification" "(LBSC)-to evaluate the MRCP examinations independently. In this classification, NAS severity is assessed in 4 hepatobiliary regions. Interobserver agreement of the severity score for each region was calculated with the κ statistics. RESULTS: Optimal cutoff value of the LBSC to detect the presence of NAS with MRCP was calculated at 3 points or greater for all readers. Applying this cutoff sensitivity for each reader was greater than 90%, with a specificity of 50% to 82%, positive predictive value of 86% to 91%, and negative predictive value of 80% to 100%. The MRCP performance was better in evaluation of the intrahepatic than of the extrahepatic bile ducts. The additional value of MRCP for grading severity of NAS was limited. CONCLUSIONS: The MRCP with the LBSC is a reliable tool to detect or exclude NAS after OLT. Currently, MRCP cannot be used to reliably grade the severity of these strictures.

Assessment of false-negative cases of breast MR imaging in women with a familial or genetic predisposition.

In order to assess the characteristics of malignant breast lesions those were not detected during screening by MR imaging. In the Dutch MRI screening study(MRISC), a non-randomized prospective multicenter study,women with high familial risk or a genetic predisposition for breast cancer were screened once a year by mammography and MRI and every 6 months with a clinical breast examination (CBE). The false-negative MR examinations were subject of this study and were retrospectively reviewed by two experienced radiologists. From November 1999 until March 2006, 2,157 women were eligible for study analyses. Ninety-seven malignant breast tumors were detected, including 19 DCIS (20%). In 22 patients with a malignant lesion, the MRI was assessed as BI-RADS 1 or 2. One patient was excluded because the examinations were not available for review. Forty-three percent (9/21) of the false-negative MR cases concerned pure ductal carcinoma in situ (DCIS) or DCIS with invasive foci, in eight of them no enhancement was seen at the review. In six patients the features of malignancy were missed or misinterpreted.Small lesion size (n = 3), extensive diffuse contrast enhancement of the breast parenchyma (n = 2),and a technically inadequate examination (n = 1) were other causes of the missed diagnosis. A major part of the false-negative MR diagnoses concerned non-enhancing DCIS, underlining the necessity of screening not only with MRI but also with mammography. Improvement of MRI scanning protocols may increase the detection rate of DCIS. The missed and misinterpreted cases are reflecting the learning curve of a multicenter study.

Dynamic contrast-enhanced MRI of the bowel wall for assessment of disease activity in Crohn's disease.

OBJECTIVE: The purpose of this study was to evaluate the role of contrast-enhanced dynamic MRI in predicting the disease activity of Crohn's disease. MATERIALS AND METHODS: Forty-eight patients in two hospitals who had clinically suspected exacerbation of Crohn's disease were included in this study. In three levels of thickened small-bowel wall, axial dynamic T1-weighted sequences were performed every 4-6 sec for a total duration of 2-3 min after contrast administration; static T1-weighted turbo spin-echo sequences were acquired both before and after contrast administration. The slope of enhancement, enhancement ratio, time to enhancement, enhancement time, and thickness of the small-bowel wall were determined. These MRI results were compared with overall clinical grade, Crohn's disease activity index (CDAI), and Van Hees activity index. Clinical grade was based on clinical information, physical findings, laboratory studies, endoscopy, surgery, and other imaging studies. Spearman's correlation coefficient and p values were determined per hospital. Fisher's z-transformation was applied before pooling the correlation coefficients from both hospitals. RESULTS: The enhancement ratio based on the static series showed significant correlation with the clinical grade (r = 0.29, p = 0.045), CDAI (r =0.31, p = 0.033), and Van Hees activity index (r = 0.36, p = 0.016). The enhancement ratio based on the dynamic series correlated significantly with the CDAI (r = 0.38, p = 0.016). Wall thickness correlated significantly with clinical grade (r = 0.47, p = 0.003) and Van Hees activity index (r = 0.41, p = 0.007). CONCLUSION: These data suggest that the enhancement ratio of bowel wall after IV administration of gadodiamide and bowel wall thickness are weak to moderate indicators of the severity of Crohn's disease.