This prospective study investigated the potential clinical and economic benefits of EUS in 485 patients suspected to have choledocholithiasis based on clinical, biochemical, and cross-sectional imaging (US or CT) data. Positive EUS findings were confirmed by endoscopic retrograde cholangiography with sphincterotomy and/or by surgery; negative findings were confirmed by clinical follow-up. The accuracy of EUS findings were confirmed as follows: 237 true-positive, 216 true-negative, 2 false-positive, 4 false-negative, 4 incomplete (sensitivity 98%, specificity 99%, positive predictive value 99%, negative predictive value 98%, accuracy 97%). In 214 (46%) patients, more invasive investigations were avoided. The mean cost for patients managed by the EUS-based strategy was significantly less than the theoretical mean cost of patients undergoing endoscopic retrograde cholangiography.

This study confirms that EUS is highly reliable for the diagnosis of choledocholithiasis which has been shown in many studies however. What is more important is that the authors showed that EUS as the first test for choledocholithiasis may offer important clinical and economic advantages by preventing ERCP induced pancreatitis and other complications in patients without significant findings in the bile duct on EUS.

The aims of this study were to determine the usefulness of peroral pancreatoscopy (POPS) and intraductal ultrasonography (IDUS) in Intraductal Papillary Mucinous Tumor (IPMT) for the differentiation of malignant from benign disease, and to evaluate the significance of these techniques as new preoperative examinations. Sixty histopathologically confirmed patients with IPMT underwent POPS and/or IDUS preoperatively. POPS was performed in all patients, and IDUS in 40. Findings of POPS and IDUS were compared with histopathology of resected specimens. Protruding lesions were detected by POPS in 40 patients. They were classified into 5 groups. Fish-egg-like type with vascular images, villous type, and vegetative type were considered to be malignant. By IDUS, lesions protruding 1 mm or more were observed in 36 patients. Of the lesions protruding 4 mm or more, 88% were malignant. Combination of POPS and IDUS improved the differential diagnosis between benign and malignant IPMT.

This is a very well done study with histopathologic correlates of peroral pancreatoscopy and intraductal ultrasound in IPMT by Japanese authors. It is a must read for anybody attempting these techniques in patients with IPMT. The images are remarkable and the authors are to be congratulated for meticulously classifying IPMT into various groups by POPS and IDUS backed with histopathologic gold standard.

This is a prospective comparison of thoracic CT, Positron emission tomography (PET), and endoscopic ultrasonography (EUS) with fine needle aspiration (FNA) for detection of lymph nodes metastases in patients with lung cancer. After bronchoscopic evaluation, CT, PET, and EUS were performed to evaluate potential mediastinal involvement in 33 consecutive patients with bronchoscopic biopsy/cytology proven (n = 25) or radiologically suspected (n = 8) lung cancer with surgical histology as "gold standard". CT, PET, and EUS detected mediastinal lymph nodes in 15, 14, and 27 patients (21 of which were suspected to be malignant on EUS), respectively. For correct prediction of mediastinal lymph node stage, the sensitivities of CT, PET, and EUS were 57%, 73%, and 94% with specificities of 74%, 83%, and 71%; accuracies were 67%, 79%, and 82%. Results of PET could be improved when combined with CT (sensitivity, 81%; specificity, 94%; accuracy, 88%). The specificity of EUS (71%) was improved to 100% by FNA cytology (EUS-guided FNA). No single imaging method alone could be considered conclusive in evaluating potential mediastinal involvement in apparently operable lung cancer under routine clinical care. A tissue diagnosis is extremely helpful and EUS with FNA combination emerged as the most useful technique in the evaluation of even very small mediastinal metastases of lung cancer. CT seems necessary additionally to evaluate the pretracheal region as well as the rest of the thorax, and PET may be valuable to detect distant metastases.

This is a well done study comparing three imaging modalities described above in a prospective fashion. This study helps clarify some of the concepts about where each of the three staging modalities-- i.e. CT, EUS, and PET-- stand if all three were easily available at an institution for staging of operable lung cancer. As shown here, these imaging modalities have their pros and cons, but one cannot claim any one of them as a complete replacement for the other. Rather, if all three are available, they may be complementary rather than competing technologies. However, when "tissue is the issue," EUS clearly is the way to go among them due to its ability to direct FNA in a safe, minimally invasive fashion.