EUS-Guided Fiducial Placement Prior to Targeted Radiation Therapy in Obese Prostate Cancer Patients...

Abstracts

other was a secondary stricture and bile leak that occurred in the stentedsegment placed for palliation of metastatic urothelial cancer to bile duct. It couldnot be determined if the bile leak was a result of malignancy, the stent, or stentremoval process. All these cases were successfully treated with repeat stenting.Conclusion: Endoscopic removal of Viabil covered self-expandable metal stentplaced for benign or malignant conditions is feasible and easily accomplished.Secondary strictures maybe found at the time of stent removal at distal margins ofoversized intraductal stents or at sites of stent angulation and malignancy andmay lead to need for repeat stenting.

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Uncovered Versus Covered Self-Expanding Metallic Stents for

Inoperable Malignant Distal Biliary Obstruction: A Prospective

Randomized Multicenter StudyYoung Deok Cho, Young Koog Cheon, Kyo-Sang Yoo, Sung-Jo Bang,Chang Duck Kim, Jae Seon Kim, Myung Hwan Roh, Ho Gak KimBackground: Endoscopic biliary drainage is widely accepted as palliativetreatment in patients with malignant inoperable biliary obstruction. However,there are few prospective comparative randomized data as to whetheruncovered or covered self-expanding metallic stents (SEMS) are preferable forpalliating malignant distal biliary obstruction. Methods: Data on patients whounderwent endoscopic retrograde biliary drainage with uncovered or coveredSEMS for the palliation of inoperable distal malignant biliary obstruction at 6university hospital were assessed prospectively. Results: Seventy-seven patientswere included in the analysis; 38 received uncovered stent (uncoveredBonastentR, Standard Scitech, Seoul, Korea or HanarostentR, M.I.Tech, Seoul,Korea) and 39 covered stent (covered BonastentR, Standard Scitech, Seoul,Korea, or covered WallstentR, Boston Scientific, USA). The overall medianpatency rates between the 2 stents did not differ (195 days for the uncoveredSEMS vs. 227 days for the covered SEMS; PO0.05). Adverse outcomes includingpancreatitis, cholescystitis or cholangitis occurred in 4/38 (10.5%) patients withuncovered versus 10/39 (26.5%) with covered SMES (PO0.05). Conclusions: Nodifference was observed between the patency and complication rates ofuncovered and covered metal stents in the management of inoperable malignantdistal biliary obstruction.

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Endoscopic Ultrasound-Guided Drainage of Pelvic and Prostatic

AbscessesRajesh Puri, Mohamad a Eloubeidi, Randhir Sud, Mandhir Kumar,Parvesh Kumar JainBackground: Pelvic and prostatic abscesses occur commonly after pelvic surgeriesand genitourinary infections. They are usually drained under radiological guidanceor surgically. We hypothesize that abscesses that are not amenable for radiologicallyguided drainage, endosonographically (EUS)-guided transrectal drainage may be aneffective alternative to surgery. Aim: To evaluate the clinical efficacy of EUS-guidedtransrectal drainage of pelvic and prostatic abscesses. Materials and Methods: Ina prospective study between July 2007 and September 2008, 10 consecutivepatients with pelvic and prostatic abscess not amenable to radiological guideddrainage underwent EUS-guided drainage. Patients were imaged by EUS within 1week after stent placement and stent was retrieved upon resolution of the abscess.Patients were then followed clinically every 7 days for 2 weeks and then every 15days for 3 months. Repeat EUS was done at 4 weeks and at 3 month. CT scan wasperformed if there was recurrence of symptoms. Results: Ten patients underwentEUS-guided pelvic and prostatic abscess drainage during the study period. Meanage of the patients was 36.5 years (range 18-67 years) and nine were male and onefemale. Etiologies of pelvic abscesses were: low anterior resection (LAR) for rectalcancer (nZ4), diverticular abscesses (nZ2), liver abscess rupture (nZ1) andinfected tubercular pelvic abscess (nZ1). Etiology of prostatic abscesses wastuberculosis and pyogenic in one each. The procedure was uneventful in allpatients. The abscess were peri-rectal (5), peri-colonic (3) and prostatic (2) withmean size of 62 x 55 mm. In pelvic abscess group (nZ8) EUS guided aspiration wassufficient in 3 patients while 2 patients required dilatation followed by aspiration.The remaining 3 with large abscesses needed transrectal stent placement. In theprostatic abscess group, aspiration alone was sufficient in one while the otherpatient required dilatation followed by aspiration. All the patients became afebrilewithin 72 hours of the aspiration. The stent was removed in all the 3 patients, afterconfirming the resolution of the abscess on repeat EUS after 7 days. One patient inwhom only aspiration was done required surgical drainage due to recurrence ofsymptoms and abscess on 7th day. Mean follow up of the patients was 5 months (15days to 260 days) after the drainage. A follow- up EUS at 3 months revealed noabscess recurrence and all the patients were asymptomatic. Conclusion: EUSguided drainage is a safe and effective modality of treatment for pelvic and prostaticabscesses not amenable to radiological guided drainage, thus avoiding surgicalintervention.

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EUS-Guided Fiducial Placement Prior to Targeted Radiation

Therapy in Obese Prostate Cancer Patients As An Alternative to

Abdominal US Prostate Localization: Results of a Single-Center

ExperienceJulie Yang, May Abdel-Wahab, Afonso C. RibeiroBackground: Image-guided radiation therapy allows the delivery of precisely aimedradiation beams to tumors while minimizing radiation to adjacent normal tissue.This is particularly important in the prostate, a moving target whose positioningdepends on the dynamics of its neighboring bladder and rectum. One method ofprostate localization prior to radiation treatment is through daily abdominal US,which is not only time-consuming but operator-dependent and limited by bodyhabitus. This could potentially be an obstacle in obese patients, where suboptimalvisualization of the prostate could occur. Alternatively, targeted radiation therapycan also be achieved using implantable radioopaque markers, or fiducials, thatserve as reference points to accurately delineate organs or tumors of interest. Aim:To describe our experience at a cancer referral center of linear array EUS-guidedplacement of fiducials in patients whose prostate was difficult to visualize byabdominal US. Methods: 16 consecutive patients with localized prostate cancer anda mean BMI of 31 underwent EUS for fiducial placement. The 3mm or 5mm x0.8mm gold markers were backloaded into a 19G FNA needle after removing thestylet and flushing the needle with saline. The stylet was reintroduced and placedapproximately 5cm before the needle tip with the gold seed in place. Fiducials weredeployed in a four-quadrant manner (bilateral base and apex) to delineate theprostate by advancing the stylet forward under real-time EUS guidance usinga linear echoendoscope. Fluoroscopic guidance was not used for fiducialplacement. Fiducial positioning was confirmed with post-procedure X-ray, as well assimulation CT. Patients received IV antibiotics prior to EUS-guided fiducialplacement and completed up to five days of PO antibiotics following the procedure.Results: Fiducial placement was successful in all patients. A total of 71 fiducials weredeployed in each corner outlining the prostate. 7/16 patients had an additionalfiducial placed to ensure adequate prostate delineation. 1 was lost in the rectumduring attempted placement. No complications developed from the procedure.Conclusion: EUS-guided placement of fiducials to facilitate image-guided radiationtherapy for prostate cancer is a feasible alternative to traditional transperineal ortransrectal US. Moreover, EUS-guided fiducial placement can be particularlyadvantageous in obese patients where prostate localization can be achievedregardless of body habitus, as compared to abdominal US localization methods.This procedure can be safely performed by endosonographers familiar withperirectal anatomy and transrectal FNA technique.

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Forward-View, Forward-Array Curvilinear Echoendoscope to

Diagnose and Sample Right-Sided Colonic LesionsThai Nguyen-Tang, Janak N. Shah, Andres Sanchez Yague, KennethF. BinmoellerBackground: Endoscopic ultrasound (EUS) examination of right colonic lesions islimited. Oblique optics of available curvilinear echoendoscopes make theseinstruments difficult and unsafe to maneuver beyond the rectosigmoid. Radial arrayEUS scopes and miniprobes do not permit tissue sampling by fine needle aspiration(FNA) or trucut biopsy. A new, forward-view, forward-array echoendoscope mayallow safe advancement to the right colon, high-quality EUS images with Dopplercapability, and EUS sampling capability. Aim: Evaluate the feasibility and safety ofa prototype forward-view, forward-array echoendoscope for right-sided coloniclesions. Methods: We used a prototype forward-array echoendoscope (XGIF-UCT160, Olympus, Tokyo, Japan) in patients referred for EUS of right colonic lesionsover a 1-year period. Clinical use for this instrument was approved by ourinstitutional review board. Following data were collected: patient demographics,clinical indications, technical success, EUS findings, and complications. Results:Eight consecutive patients were referred for EUS of right colon lesions. Abnormaliteswere found on prior colonoscopy or CT scan, and were located near the cecum (6),or ascending colon (2). EUS indications included: submucosal mass (6), evaluationof pericolonic lymph node (1), and infiltrative colonic mass with non-diagnosticmucosal biopsies (1). The cecum was reached in all exams within 10 min ofinsertion. Median procedure time was 42 min (22-58). EUS findings in patients withsubmucosal lesions included: spindle cell tumor confirmed by EUS-FNA (1), calcifiedlymph node compressing lumen (1), and extrinsic compression from normalabdominal structures (4). The patient referred for a pericolonic lymph node wasincidentally found to have a flat colonic mass. The lymph node was visualized byEUS, and FNA revealed carcinoma. The patient referred for an infiltrative mass (priornon-diagnostic biopsies) had diffuse wall thickening. EUS-FNA of the deep aspect ofthe colonic wall revealed histoplasmosis. Overall, EUS-FNA was performed in 4, andprovided diagnostic samples in 75%. The FNA from the calcified appearing lymphnode was non-diagnostic. There were no procedural complications. Conclusions:Use of a prototype forward-view, forward-array echoendoscope to evaluate right-sided colonic lesions appears feasible and safe. This echoendoscope with FNA/trucut capability could be a valuable tool for investigating proximal colonicabnormalities. A potential limitation of the instrument is the shorter insertion tubelength (125cm) compared to a standard colonoscope.

lume 69, No. 5 : 2009 GASTROINTESTINAL ENDOSCOPY AB137