I R Francis

Iodine-131-anti-B1 radioimmunotherapy for B-cell lymphoma.

PURPOSEnThe CD20 B-lymphocyte surface antigen expressed by B-cell lymphomas is an attractive target for radioimmunotherapy, treatment using radiolabeled antibodies. We conducted a phase I dose-escalation trial to assess the toxicity, tumor targeting, and efficacy of nonmyeloablative doses of an anti-CD20 monoclonal antibody (anti-B1) labeled with iodine-131 (131I) in 34 patients with B-cell lymphoma who had failed chemotherapy.nnnPATIENTS AND METHODSnPatients were first given tracelabeled doses of 131I-labeled anti-B1 (15 to 20 mg, 5 mCi) to assess radiolabeled antibody biodistribution, and then a radioimmunotherapeutic dose (15 to 20 mg) labeled with a quantity of 131I that would deliver a specified centigray dose of whole-body radiation predicted by the tracer dose. Whole-body radiation doses were escalated from 25 to 85 cGy in sequential groups of patients in 10-cGy increments. To evaluate if radiolabeled antibody biodistribution could be optimized, initial patients were given one or two additional tracer doses on successive weeks, each dose preceded by an infusion of 135 mg of unlabeled anti-B1 one week and 685 mg the next. The unlabeled antibody dose resulting in the most optimal tracer biodistribution was also given before the radioimmunotherapeutic dose. Later patients were given a single tracer dose and radioimmunotherapeutic dose preceded by infusion of 685 mg of unlabeled anti-B1.nnnRESULTSnTreatment was well tolerated. Hematologic toxicity was dose-limiting, and 75 cGy was established as the maximally tolerated whole-body radiation dose. Twenty-eight patients received radioimmunotherapeutic doses of 34 to 161 mCi, resulting in complete remission in 14 patients and a partial response in eight. All 13 patients with low-grade lymphoma responded, and 10 achieved a complete remission. Six of eight patients with transformed lymphoma responded. Thirteen of 19 patients whose disease was resistant to their last course of chemotherapy and all patients with chemotherapy-sensitive disease responded. The median duration of complete remission exceeds 16.5 months. Six patients remain in complete remission 16 to 31 months after treatment.nnnCONCLUSIONnNonmyeloablative radioimmunotherapy with 131I-anti-B1 is associated with a high rate of durable remissions in patients with B-cell lymphoma refractory to chemotherapy.

Can endoscopic ultrasound or magnetic resonance cholangiopancreatography replace ERCP in patients with suspected biliary disease? A prospective trial and cost analysis.

OBJECTIVES:ERCP is the gold standard for pancreaticobiliary evaluation but is associated with complications. Less invasive diagnostic alternatives with similar capabilities may be cost-effective, particularly in situations involving low prevalence of disease. The aim of this study was to compare the performance of endoscopic ultrasound (EUS) with magnetic resonance cholangiopancreatography (MRCP) and ERCP in the same patients with suspected extrahepatic biliary disease. The economic outcomes of EUS-, MRCP-, and ERCP-based diagnostic strategies were evaluated.METHODS:Prospective cohort study of patients referred for ERCP with suspected biliary disease. MRCP and EUS were performed within 24 h before ERCP. The investigators were blinded to the results of the alternative imaging studies. A cost-utility analysis was performed for initial ERCP, MRCP, and EUS strategies for these patients.RESULTS:A total of 30 patients were studied. ERCP cholangiogram failed in one patient, and another patient did not complete MRCP because of claustrophobia. The final diagnoses (n = 28) were CBD stone (mean = 4 mm; range = 3–6 mm) in five patients; biliary stricture in three patients, and normal biliary tree in 20. Two patients had pancreatitis after therapeutic ERCP, one after precut sphincterotomy followed by a normal cholangiogram. EUS was more sensitive than MRCP in the detection of choledocolithiasis (80%vs 40%), with similar specificity. MRCP had a poor specificity and positive predictive value for the diagnosis of biliary stricture (76%/25%) compared to EUS (100%/100%), with similar sensitivity. The overall accuracy of MRCP for any abnormality was 61% (95% CI = 0.41–0.78) compared to 89% (CI = 0.72–0.98) for EUS. Among those patients with a normal biliary tree, the proportion correctly identified with each test was 95% for EUS and 65% for MRCP (p < 0.02). The cost for each strategy per patient evaluated was

CT time-attenuation washout curves of adrenal adenomas and nonadenomas.

1346 for ERCP,

Differentiation of adrenal adenomas from nonadenomas using CT attenuation values.

1111 for EUS, and

Adrenal adenomas: relationship between histologic lipid and CT and MR findings.

1145 for MRCP.CONCLUSIONS:In this patient population with a low disease prevalence, EUS was superior to MRCP for choledocholithiasis. EUS was most useful for confirming a normal biliary tree and should be considered a low-risk alternative to ERCP. Although MRCP had the lowest procedural reimbursement, the initial EUS strategy had the greatest cost-utility by avoiding unnecessary ERCP examinations.