Nobumasa Mizuno

Diagnostic utility of EUS-guided FNA in patients with gastric submucosal tumors

BACKGROUNDnSubmucosal tumors (SMTs) comprise both benign and malignant lesions, and most of the gastric lesions tend to be malignant. The addition of EUS-guided FNA (EUS-FNA) has the potential to improve this distinction, but published series are limited.nnnOBJECTIVEnTo evaluate the yield of EUS-FNA in gastric SMTs with referral to a criterion standard final diagnosis.nnnDESIGNnRetrospective study.nnnSETTINGnTertiary-care referral center.nnnPATIENTSnThis study involved 141 consecutive patients with gastric SMTs, who underwent EUS-FNA from January 2000 to December 2008. Immunohistochemical staining with c-kit, CD34, actin, and S-100 antibodies was done if a spindle cell tumor was found. Based on FNA sample adequacy, and whether a specific diagnosis could be established, EUS-FNA results were categorized as diagnostic, suggestive, or nondiagnostic. The criterion standards for final diagnosis were the surgical histopathological results or the follow-up course for malignant, inoperable cases.nnnINTERVENTIONnEUS-FNA.nnnMAIN OUTCOME MEASUREMENTSnDiagnostic yield of EUS-FNA and factors related to sampling adequacy for cytological and immunohistochemical evaluation.nnnRESULTSnA total of 141 patients (52% female, mean age 56.7 years) underwent EUS-FNA (range 1-5 passes). The overall results of EUS-FNA were diagnostic, suggestive, and nondiagnostic in 43.3%, 39%, and 17.7% of cases, respectively. Adequate specimens were obtained in 83% of cases, and 69 cases (48.9%) had a definitive final diagnosis. The most common gastric SMT was GI stromal tumor (59.5%). EUS-FNA results were 95.6% accurate (95% confidence interval [CI], 87.5%-99%) for the final diagnosis and 94.2% (95% CI, 85.6%-98.1%) accurate for differentiating potentially malignant lesions. A heterogeneous echo pattern was the only independent predictor for sampling adequacy (adjusted odds ratio 6.15; P = .002). There were no procedure-related complications.nnnLIMITATIONSnPossibility of selection bias.nnnCONCLUSIONnEUS-FNA is an accurate method for diagnosis of gastric SMTs and for differentiating malignant lesions.

EUS-BD and EUS-GBD

Endoscopic retrograde cholangiopancreatography (ERCP) has become the standard tool for diagnosis and treatment of patients with biliary obstruction. However, ERCP occasionally fails owing to anatomical or technical problems, despite high reported success rates. Endoscopic ultrasound-guided biliary drainage (EUS-BD) has recently emerged as an effective alternative biliary drainage method over percutaneous transhepatic biliary drainage (PTBD) after unsuccessful ERCP. EUS-BD includes EUS-rendezvous technique, EUS-guided transluminal biliary drainage including choledochoduodenostomy and hepaticogastrostomy, and EUS-guided gallbladder drainage (EUS-GBD).

Early Diagnosis of Pancreatic Cancer Using Endoscopic Ultrasound

Despite a low incidence, the mortality rate of pancreatic cancer (PC) is high. Early detection and optimal treatment based on the findings of various imaging modalities are essential to improve the survival rate of patients with PC. Multi-detector (MD) row computed tomography (CT) is currently the standard imaging modality for evaluating PC worldwide. However, 10% of PC tumors can be iso-attenuated on CT and thus invisible, especially when ≤2 cm. Endoscopic ultrasonography (EUS) can detect tumors that are <10 cm at a higher rate than CT and might be useful for diagnosing high-grade pancreatic intraepithelial neoplasia (PanIN3) as well as magnetic resonance cholangiopancreatography, as they can both detect local irregular stenosis of the pancreatic duct.

A Role of PET/CT in the Diagnosis of Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP) is a special entity of chronic pancreatitis of presumed autoimmune etiology that is associated with characteristic clinical, histological, and morphological findings [1, 2]. Over the last decade, significant progress has been made in understanding this disease, including identification of two distinct histological subtypes with different clinical phenotypes (termed type 1 and type 2 AIP), incorporation of seemingly unrelated diseases within the spectrum of IgG4-related disease [2–4]. Despite advances, many questions remain unanswered. Among the remaining questions, distinguishing AIP from pancreatic cancer is still challenging. AIP mimics pancreatic cancer in terms of clinical features, such as advanced age, painless jaundice, weight loss, new-onset diabetes mellitus, and the presence of a mass lesion of the pancreas [1, 5].