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Endoscopic ultrasound-guided fine-needle aspiration in idiopathic abdominal masses and miscellaneous nongastrointestinal lesions
Endoscopic Ultrasound-Guided Fine-Needle Aspiration in Idiopathic Abdominal Masses and Miscellaneous Nongastrointestinal Lesions Marc E Catalano, MD, FACG, FACP
Advancement in endoscopic ultrasound (EUS), particularly fine-needle aspiration (FNA) biopsy, has further increased the diagnostic capability of endosonography. Well-established indications of EUS-guided FNA have included confirmation of suspected malignancy of pancreatic lesions, submucosal tumors, and lymph node metastases (gastrointestinal lesions). Recently, the application of FNA technology also has proved beneficial in the evaluation and diagnosis of nongastrointestinaP diseases. The most promising area is staging of non-small-cell lung cancer, which is much superior to computed tomography (CT) scan and similar to mediastinoscopy. Other potential areas of application include lesions of the kidney and adrenal glands, pelvic organs (prostate, ovaries), as well as idiopathic abdominal and mediastinal masses. Furthermore, these results have been shown to assist in guiding subsequent therapy and establishing prognosis in most patients studied. Copyright 9 2000 by W.B. Saunders Company
assist in cancer staging by documenting regional lymph node metastasis of GI malignancies. ~s,2~ The application of fine-needle aspiration (FNA) technology also can be helpful in diagnosis of non-GI diseases. 33-42 A relatively new use of EUS-guided FNA is emerging for staging non-small-cell lung cancer that is much superior to computed tomography and less invasive than mediastinoscopy. 33 A positive EUS-guided cytology can have a major impact in the management of patients. Initial reports put the accuracy of EUS-guided FNA for this purpose in the range of greater than 90%. The added ability to perform EUS-guided FNA has overcome some of the specificity problems associated with EUS in distinguishing benign from malignant lesions.
Nongastrointestinal Abdominal Masses
Kidney--Adrenal ndoscopic ultrasound (EUS) is a well-established imaging
E modality in the evaluation of a variety of gastrointestinal disorders. M7 Endoscopic placement of the ultrasound transducer immediately adjacent to the area of interest has allowed the use of higher frequencies, thus permitting greater spatial resolution. The ability to image the wall of the gastrointestinal tract as a series of definable layers corresponding to histology, rather than a single entity, results in a powerful clinical tool and is the basis of most of the indications for EUS. Other indications have emerged from the ability of EUS to provide detailed images of the areas in immediate proximity to the gastrointestinal tract and to guide needles precisely through the gut wall and surrounding structures. 18-32 Indications for EUS can be divided into 3 main categories: (1) submucosal abnormalities, (2) cancer staging, and (3) pancreatic biliary disease. EUS can make a difference in all of these clinical areas and can be performed with a low complication rate similar to diagnostic endoscopy. As an extension of imaging, several reports have described the use of endosonography in conjunction with needle aspiration biopsy to sample lesions within and adjacent to the gastrointestinal (GI) tract.18-32 The technique is also good in confirming suspected malignancy of pancreatic lesions and submucosal tumors. They also
From the Medical College of Wisconsin, St Lukes Medical Center, and Pancreatic Biliary Center, Milwaukee, WI. Address reprint requests to Marc F. Catarano, MD, FACG, FACP, 2801 Kinnickinnic River Pkwy #570, Milwaukee, W153215. Copyright 9 2000 by W.B. Saunders Company 1096-2883/00/0203-0007510.00/0 doi:10.1053/tgie.2000.7741
The relative high frequency of renal lesions, both cystic and solid, provides a potential new indication for endosonography. The proximity of the kidney to the GI tract, particularly the left, allows easy targeting of these lesions in question, including primary (renal cell carcinoma) and metastatic. Similarly, because of the intimate association of the adrenal glands, these structures can also be imaged and targeted for fine-needle aspiration. 3s Imaging. The left kidney is imaged using radial uhrasonography by advancing the echoendoscope to the gastric cardia where the abdominal aorta is noted in its transverse section and placed at the 6-o'clock position. Advancement along the greater curvature of the stomach initially brings into view the spleen, followed shortly by the left kidney and adrenal gland, along with the left renal vein and artery. Just proximal to the celiac axis, the left adrenal usually can be seen as an echolucent thin strip of tissue to the left of the aorta. It can appear as a long stripe or m a "seagull" shape. The adrenal cortex is generally more echolucent than the echogenic medullary portion. Adrenal adenomas are seen in 2% to 3% of normal patients and appear as ovoid or round homogenous masses occupying part of the adrenal gland. 3s Alternatively, the left kidney can be followed cephalad to view the left adrenal on the medial side of the upper pole. Deep advancement of the echoendoscope into the duodenum shows landmark structures, side-by-side cross section of the inferior vena cava and abdominal aorta. Small adjustments may allow visualization of the right kidney just lateral to these structures. After advancement of the linear echoendoscope in preparation for YNA, the abdominal aorta is used as a landmark structure. This is initially picked up at the level of the
Techniques in Gastrointestinal Endoscopy, Vol 2, No 3 (July), 2000: pp 159-164
159
Fig 1. CT scan showing a 6-cm mass anterior to left kidney,
gastroesophageal junction by rotating clockwise or counterclockwise. From this level, rotating slightly clockwise while advancing the instrument a few centimeters will enable the endosonographer to view both the left adrenal and accompanying kidney. This can be considerably more difficult to visualize than with radial technology. Even more challenging is the visualization of the right kidney and adrenal. This can be accomplished by advancing the linear array echoendoscope to the level of the ampulla. Retraction and slight rotation brings into view the portal vein and common bile duct. Further retraction and rotation can bring these 2 organs into view for FNA. Literature. The application of EUS in imaging the kidneys and the adrenal glands has been reported by Chang et al. 3s Thirty-one consecutive patients presenting with known malignancies of the lung or gastrointestinal tract were evaluated for metastasis to the adrenal glands. In 30 of 31 patients (97%), the left adrenal gland was fully characterized. EUS-guided FNA of the adrenal gland was performed in 1 patient with lung cancer suspected of having metastatic disease. Results showed malignant involvement of the left adrenal gland, thus avoiding operative resection.
Although imaging of the kidneys has been described in limited detail by few investigators, only 1 report has described EUS-guided FNA and diagnosis of renal tumors. Faigel et a139 reported a total of 23 extraluminal EUS-guided FNA cases. One patient had a known mass involving the left kidney. Although
Fig 2. EUS of patient in Figure I showing a mixed echogenic mass. EUS-guided FNA is performed.
Fig 4. EUS showing a 3-cm hypoechoic mass within to the left lobe of the liver.
160
Fig 3. Histology of EUS FNA of patient in Figures I and 2, showing a ganglioneuroma (provided by Richard A Erickson, MD).
MARC E CATALANO
TABLE 1. Results of EUS-Guided FNA of 34 Patients Presenting With Abdominal Masses
Disease Classification Infectious Benign/inflammatory Malignant Total
Fig 5. EUS FNA of patient in Figure 7.
cytology showed benign cells, long-term follow-up showed renal cell carcinoma. Both the left and right kidney can nonetheless be approached using EUS-guided FNA tissue sampling. In a study evaluating imaging of retroperitoneal organs by EUS in 604 consecutive patients, the left kidney was shown in 530 cases (88%) and the right kidney in 554 (90%) patients. 4~ In a multicenter report of 142 consecutive cases of non-GI EUS/ FNA, 7 patients had either renal (n = 4) or adrenal (n = 3) lesions 36 (Figs 1-3). Successful cytological sampling was reported in all 7 patients (100%), with all but 1 lesion showing benign disease (adrenal adenoma).
Ovaries~Uterus Female reproductive organs have shown increasing incidence of malignant disease, which frequently requires biopsy before definitive treatment. Endorectal ultrasonography allows for the close proximity imaging of these structures, particularly those of the left adnexa. Imaging. The examination of the rectum and surrounding structures, including uterus and adnexa, can best be imaged on withdrawal of the radial echoendoscope from the sigmoid
FNA Passes Patient Range No. (Mean) 5 6 23 34
1-4 (2.2) 2-4 (3.2) 2-9 (4.6) 1-9 (3.8)
EUS Dx Alters EUS FNA Diagnostic Workup Therapy n (%) n (%) n (%) 4 (80) 4 (67) 21 (91) 29 (85)
4 4 21 29
(80) (67) (91) (85)
4 (80) 3 (50) 19 (83) 26 (77)
colon. At this level, depending on the shape of the sigmoid colon, the left ovary occasionally can be seen. The uterus next appears between the rectum and the bladder, and because of the very dense muscular organ, it can occasionally be difficult to see beyond this structure. Further withdrawal brings into view the vagina, which appears anteriorly as a flattened, inverted, "U-shaped" structure with a thin bright stripe of air within it. Deep to the vagina, the cross-sectional urethra with its surrounding sphincter appears as a circular echolucent structure. Withdrawal of the linear echoendoscope from the sigmoid colon will bring the uterus into view, with the bladder located more deeply. Occasionally, the left adnexal structure also can be seen on deep insertion near the pelvic rim vessds. Further withdrawal from the level of the uterus will show a landmark structure view of the "air stripe" of the vaginal cavity anteriorly, with portions of the urethra seen deep to it. Literature. Very little is written in literature regarding EUS-guided FNA of female reproductive organs. 41 This is particularly related to the inability to image the right ovary and the less than optimal visualization of the left ovary. In a study previously addressed, only 2 of a 142 patients who presented with non-GI lesions underwent EUS-guided FNA (2 ovarian lesions).36 Both patients had a correct diagnosis established by EUS FNA.
Prostate Lesions of the prostate are quite common but infrequently present to the gastroenterologist. Under such a circumstance they often present with rectal symptoms (ie, pain or bleeding) from the extension of the lesion through the rectal wall. Endosonography in this instance could allow for the correct diagnosis and establish extent of the disease. Imaging. The radial echoprobe is advanced beyond the rectum into the sigmoid colon. When the echoprobe is withdrawn to 10 to 15 cm from the anal verge, the seminal vesicles appear initially as a pair of echolucent ovoid structures anterior to the rectum. On further withdrawal, the right and left seminal vesicles merge into a single longitudinal structure
TABLE 2. Results of EUS-Guided FNA of 26 Patients Presenting With Mediastinal Masses
Disease Classification
Fig 6. Histology of patient in Figures 7 and 8 showing metastatic adenocarcinoma. EUS-GUIDED FNA IN ABDOMINAL MASSES
Infectious Benign/inflammatory Malignant Total
FNA Passes Patient Range No. (Mean) 5 9 12 26
1-5 (3.4) 2-3 (3.0) 1-7 (4.4) 1-7 (3.8)
EUS Dx Alters EUS RNA Diagnostic Workup Therapy (%) (%) (%) 3 (60) 7 (78) 11 (92) 21 (81)
3 (60) 6 (67) 11 (92) 20 (77)
3 (60) 7 (78) 9 (75) 19 (73) 1 61
Fig 9. Histology of patient in Figures 7 and 8 showing adenocarcinoma.
Liver Fig 7. EUS showing a 4.2-cm mediastinal mass adjacent to the esophagus at 25 cm.
between the rectum and bladder. With the probe further retracted, the prostate can be seen as a semicircular structure in the anterior perirectal region. On linear imaging, the probe is again placed to the left of the sigmoid colon and slowly withdrawn to 7 to 12 cm. Here, rotation to the right or left will bring into view the prostate. Just proximal to the prostate, one can view the seminal vesicle. Literature. In the only report of EUS-guided FNA of the prostate, 4 patients presented with prostatic lesions, with invasion of adjacent structures in 3 of the patients (75%). 36 These were successfully imaged and biopsies were performed, with an accurate diagnosis achieved in all patients (100%), including 3 malignant and 1 benign lesion.
Fig 8. EUS FNA of patient in Figure 7. 162
The liver represents the organ most commonly affected by metastatic disease. In addition, numerous primary malignant and benign lesions of the liver are described. Occasionally, metastatic lesions of the liver are not identified preoperatively in patients with primary malignancy elsewhere and are noted either intraoperatively or at intervals postoperatively. Endosonography, until recently, has not traditionally been thought to be applicable in the detection or evaluation of existing liver metastasis (Figs 4-6). Imaging. On entering the abdomen with the radial echoendoscope, the left lobe of the liver dominates the view. Near the hiatus, the hepatic veins are seen draining into the inferior vena cava. The remaining left lobe of the liver and parts of the right lobe can be visualized by advancing the probe down the lesser curvature of the stomach toward the antrum. The liver hilum can be examined by placing the probe within the duodenum and slowly retracting toward the duodenum with upward tip deflection.
Fig 10. EUS depicting a 4-cm mediastinal mass in a patient presenting with dysphagia and chest pain, MARC E CATALANO
Literature. In a prospective study, Nguyen et a143 evaluated 574 consecutive patients for liver metastasis with a history or suspicion of GI or pulmonary malignant tumors by EUS. Fourteen (2.4%) were found to have 15 focal liver lesions and underwent EUS-guided FNA. The median largest diameter of the liver lesion was 1.1 cm. All FNA samples yielded adequate specimens. Fourteen of 15 lesions aspirated were malignant. Only 3 of 14 patients had demonstrable lesions on computed tomography (CT) scan.
Intra-abdominal Mass--Nongastrointestinal Intra-abdominal masses from specific organs are occasionally encountered, including malignant disease (lymphoma, sarcoma) and benign lesions (leiomyoma, abscess). The role of EUS-guided FNA to establish diagnosis of such idiopathic abdominal masses has not been previously described. In a recent muhicenter study, 42 34 patients underwent EUS-guided FNA in patients with idiopathic abdominal masses at 5 tertiary centers. Four of 34 patients had history of intra-abdominal cancers (cervical = 2, ovarian cancer = 1, colon cancer = 1). Final diagnosis using EUS FNA, surgery, autopsy, or long-term follow-up was available in all patients (Table 1). EUS FNA results were classified under 3 disease categories: infectious, benign/inflammatory, and malignant. Final diagnosis included infectious (n = 5), benign/inflammatory (n = 6), and malignant abdominal (n = 23). EUS-guided FNA was successful in establishing a tissue diagnosis in 29 of 34 patients (85%) for all 3 categories. EUS-guided FNA was successful in directing subsequent workup in 85% and subsequent therapy in 77% of patients.
Idiopathic Mediastinal Masses Mediastinal masses occasionally present a diagnostic challenge. Methods of tissue sampling have traditionally included mediastinoscopy and bronchoscopy with varying efficacy. A more reliable method of evaluation, including tissue sampling,
Fig 12. Histology of patient in Figures 10 and 11 showing large cell lymphoma.
may be EUS-guided FNA. The role of EUS-guided FNA to establish the diagnosis of idiopathic mediastinal masses has been limited. 34,35,44 In a recent study by Catalano et al, 37 26 patients, including 15 men and 1l women (age range 39-77; mean, 61) underwent EUS-guided FNA in patients with idiopathic mediastinal masses at 4 tertiary referral centers (Table 2). Presenting symptoms included chest pain = 10, dysphagia = 8, cough = 7, fever = 6, night sweats = 3, and no symptoms/abnormal radiograph = 5. Five of 26 patients had history of cancer (3 lung, 1 tracheal, and 1 esophageal). Final diagnosis using EUS FNA, surgery, autopsy, and other diagnostic study or long-term follow-up was available in all patients. EUS FNA results were classified under 3 disease categories: infectious, benign/ inflammatory, and malignant. Follow-up diagnosis included infectious = 5, benign/inflammatory -- 9, malignant = 12 (Figs 7-12). EUS-guided FNA was successful in 21 of 26 patients (81%) for all disease categories (infectious, 60%; benign/inflammatory, 78%; and malignant, 92%). EUS FNA was successful in directing subsequent workup in 77% (20 of 26) and therapy in 73% (19 of 26). EUS-guided FNA passes for adequate tissue sampling was lower for nonmalignant disease categories (3.0 to 3.4) versus malignant disease (4.4). No complications were seen during the course of the study. In conclusion, EUS-guided FNA in idiopathic abdominal and mediastinal masses as well as a variety of miscellaneous non-GI lesions provides excellent imaging and diagnostic accuracy in most patients. These results assist in guiding subsequent therapy and establishing prognosis in these patients.
References
Fig 11. EUS FNAof patient in Figure 10. EUS-GUIDED FNA IN ABDOMINAL MASSES
1. Yanai H, Matsumoto Y, Harada T, et al: Endoscopic ultrasonography and endoscopy for staging depth of invasion in early gastric cancer: A pilot study. Gastrointest Endosc 46:212-216, 1997 2. Botet JF, Lightdale CJ, Zauber AG, et al: Preoperative staging of esophageal cancer: Comparison of endoscopic US and dynamic CT. Radiology 181:419-425, 1991 3. Ziegler K, Sanft C, Friedrich M, et al: Evaluation of endosonography in TN staging of esophagealcancer. Gut 32:16-20, 1991 4. Ziegler K, Sanft C, Zimmer T, et al: Comparison of computed tomography, endosonography, and intraoperative assessment in TNM staging of gastric carcinoma, Gut 34:604-610, 1993
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5. Palazzo L, Roseau G, Ruskone Fourrmetrauz A, et al: Endoscopic ultrasonography in the local staging of primary gastric lymphoma. Endoscopy 25:502-508, 1993 6. Glaser F, Schlag P, Heffarth C: Endorectal ultrasonography for the assessment of invasive rectal tumors and lymph node involvement. Br J Surg 77:833-837, 1990 7. Shimizu S, Tada M, Kawai K: Use of endoscopic ultrasonography for the diagnosis of colorectal tumors. Endoscopy 22:31-34, 1990 8. Howard TJ, Chin Ac, Streib EW, et al: Value of helical computed tomography, angiography, and endoscopic ultrasound in determining resectability of periampullary carcinoma. Am J Surg 174:237-241, 1997 9. RSsch T: Staging pancreatic cancer: Analysis of literature results. Gastrointest Endosc Clin North Am 5:735-739, 1995 10. Yasuda K, Mukai H, Nakajima M, et al: Staging of pancreatic carcinomas by endoscopic ultrasonography. Endoscopy 25:151-155, 1993 11. Zimmer R, Ziegler K, Bader M: Localization of neuroendocrine tumors of the upper GI tract. Gut 35:471-475, 1994 12. Chak A, Canto MI, R6sch T, et al: Endosonographic differentiation of benign and malignant stromal cell tumors. Gastrointest Endosc 45:468-473, 1997 13. Sahai AV, Zimmerman M, Aabakken L, et al: Prospective assessment of the ability of endoscopic ultrasound to diagnose, exclude, or establish the severity of chronic pancreatitis found by endoscopic retrograde cholangiopancreatography. Gastrointest Endosc 48:1825, 1998 14. Catalano MF, Lahoti S, Geenen JE, et al: Prospective evaluation of endoscopic retrograde pancreatography, and secretin test, in the diagnosis of chronic pancreatitis. Gastrointest Endosc 48:11-17, 1998 15. Nickl NJ, Bhutani M, Catalano MF, et al: Clinical implications of endoscopic ultrasound: The American Endosonography Club Study. Gastrointest Endosc 44:371-377, 1996 16. Catalano MF, Sivak MV, Rice T, et al: Endosonographic features predictive of lymph node metastasis. Gastrointest Endosc 40:442446, 1994 17. Bhutani MS, Hawes RH, Hoffman BJ: Acomparison of the accuracy of echo features during endoscopic ultrasound (EUS) and EUS-guided fine needle aspiration for diagnosis of malignant lymph node invasion. Gastrointest Endosc 45:474-479, 1997 18. Ikenberry S, Gress FG, Savides TA, et al: Fine needle aspiration of posterior mediastinal lymph nodes guided by radial scanning endosonography. Gastrointest Endosc 43:605-610, 1996 19. Wiersema M, Hawes RH, Tao LC, et al: Endoscopic ultrasonography as an adjunct to fine needle aspiration cytology of the upper and lower gastrointestinal tract. Gastrointest Endosc 38:35-39, 1992 20. Wiersema MJ, Kochman ML, Chak A, et al: Real-time endoscopic ultrasound-guided fine-needle aspiration of a mediastinal lymph node. Gastrointest Endosc 39:429-431,1993 21. Vilmann P, Hancke S, Hendricksen FW, et al: Endosonographicallyguided fine needle aspiration biopsy of malignant lesions in the upper gastrointestinal tract. Endoscopy 25:523-527, 1993 22. Chang KJ, Nguyen P, Ericson RA, et al: The clinical utility of endoscopic ultrasound-guided fine-needle aspiration in the diagnosis and staging of pancreatic carcinoma. Gastrointest Endosc 45:387393, 1997 23. Gress FG, Hawes RH, Savides TJ, et al: Endoscopic ultrasoundguided fine-needle aspiration biopsy using linear array and radial scanning endosonography. Gastrointest Endosc 45:243-250, 1997 24. Harada N, Kouzu T, Arima M, et al: Endoscopic ultrasound-guided histologic needle biopsy: Preliminary results using a newly developed endoscopic ultrasound transducer. Gastrointest Endosc 44:327-330, 1996 25. Chang KJ, Katz K, Durbin TE: Endoscopic ultrasound-guided fineneedle aspiration, Gastrointest Endosc 40:694-699, 1994
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26. Giovannini M, Seitz JF, Monges G: Fine-needle aspiration cytology guided by endoscopic ultrasonography: Results in 141 patients. Endoscopy 27:171-177, 1995 27. Vilmann P, Hancke S, Henriksen FW: Endoscopic ultrasonographyguided fine-needle aspiration biopsy of lesions in the upper gastrointestinal tract. Gastrointest Endosc 41:230-235, 1995 28. Vilmann P, Jacobsen GK, Henriksen FW, et al: Endoscopic ultrasonography with guided fine-needle aspiration in pancreatic disease. Gastrointest Endosc 38:172-173, 1992 29. Tio TL, Sie LH, Tytgat GNJ: Endosonography and cytology in diagnosing and staging pancreatic body and tail carcinoma: Preliminary results of endosonographic guided puncture. Dig Dis Sci 38:5964, 1993 30. Chang KJ, Wiersema MJ: Endoscopic ultrasound-guided fine-needle aspiration biopsy and interventional endoscopic ultrasonography: Emerging technologies. Gastrointest Endosc Clin North Am 7:221235, 1997 31. Catalano MF, Hoffman B, Bhutani M, et al: Endoscopic ultrasound (EUS) guided fine-needle aspiration (FNA) of gastrointestinal (GI) tract lesions: A multicenter assessment of accuracy, complication rate and technical competence. Gastrointest Endosc 45:AB26, 1997 32. Wiersema MJ, Vilmann P, Giovannnini M, et al: Endosonographyguided fine needle aspiration biopsy: Diagnostic accuracy and complication assessment. Gastroenterology 112:1087-1095, 1997 33. Gress FG, Savides T J, Sandier A, et al: Endoscopic ultrasonography, fine needle aspiration biopsy guided by endoscopic ultrasonography and computed tomography in the preoperative staging of non-smallcell lung cancer: A comparison study. Ann Intern Med 127:604-612, 1997 34. Rex DK, Tarver RD, Wiersema M, et al: Endoscopic transesophageal fine needle aspiration of mediastinal masses. Gastrointest Endosc 37:465-468, 1991 35. Wegener M, Adamek RJ, Wedmann B, et al: Endosonographically guided fine-needle aspiration puncture of paraesophagogastric mass lesions: Preliminary results. Endoscopy 26:586-591, 1994 36. Catalano MF, Hoffman B, Bhutani M, et al: Endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) in non-gastrointestinal (GI) disorders: A multicenter assessment on accuracy and therapeutic guidance. Gastrointest Endosc 45:AB26, 1997 37. Catalano MF, ChakA, Sivak MV, et al: Endoscopic ultrasound guided fine needle aspiration in the diagnoses of mediastinal masses of unknown cause. Gastrointest Endosc 49:AB143, 1999 (abstr 395) 38. Chang KJ, Erikson RA, Nguyen P: Endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration of the left adrenal gland. Gastrointest Endosc 44:568-572, 1996 39. Faigel DO, Ginsberg GG, Kadish SL, et al: Endoscopic ultrasound (EUS) guided fine-needle aspiration (FNA) of extraluminal masses. Gastroenterology 110:A511,1996 40. Catalano MF, Geenen JE, Schmalz MJ, et al: Evaluation of retroperitoReal structures during radial scanning endoscopic ultrasound (EUS). Gastroenterology 110:A9, 1996 41. Hoffman B, Bhutani M, Aabakken L, et al: Endoscopic ultrasoundguided fine needle aspiration in the evaluation of extrarectal pelvic masses. Gastrointest Endosc 43:A423, 1996 42. Catalano MF, Doos W, Sivak MV, et al: Endoscopic ultrasound guided fine needle aspiration of idiopathic abdominal masses. Gastrointest Endosc 49:153, 1999 (abstr 396) 43. Nguyen P, Feng JC, Chang KJ: Endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration (FNA) of liver lesions. Gastrointest Endosc 50:357-361, 1999 44. Wiersema MJ, Gatzimos K, Nisi R, et al: Staging of non-Hodgkin's gastric lymphoma with endosonography-guided fine-needle aspiration biopsy and flow-cytometry. Gastrointest Endosc 44:734-736, 1996
MARC F. CATALANO
Advancement in endoscopic ultrasound (EUS), particularly fine-needle aspiration (FNA) biopsy, has further increased the diagnostic capability of endosonography. Well-established indications of EUS-guided FNA have included confirmation of suspected malignancy of pancreatic lesions, submucosal tumors, and lymph node metastases (gastrointestinal lesions). Recently, the application of FNA technology also has proved beneficial in the evaluation and diagnosis of nongastrointestinaP diseases. The most promising area is staging of non-small-cell lung cancer, which is much superior to computed tomography (CT) scan and similar to mediastinoscopy. Other potential areas of application include lesions of the kidney and adrenal glands, pelvic organs (prostate, ovaries), as well as idiopathic abdominal and mediastinal masses. Furthermore, these results have been shown to assist in guiding subsequent therapy and establishing prognosis in most patients studied. Copyright 9 2000 by W.B. Saunders Company
assist in cancer staging by documenting regional lymph node metastasis of GI malignancies. ~s,2~ The application of fine-needle aspiration (FNA) technology also can be helpful in diagnosis of non-GI diseases. 33-42 A relatively new use of EUS-guided FNA is emerging for staging non-small-cell lung cancer that is much superior to computed tomography and less invasive than mediastinoscopy. 33 A positive EUS-guided cytology can have a major impact in the management of patients. Initial reports put the accuracy of EUS-guided FNA for this purpose in the range of greater than 90%. The added ability to perform EUS-guided FNA has overcome some of the specificity problems associated with EUS in distinguishing benign from malignant lesions.
Nongastrointestinal Abdominal Masses
Kidney--Adrenal ndoscopic ultrasound (EUS) is a well-established imaging
E modality in the evaluation of a variety of gastrointestinal disorders. M7 Endoscopic placement of the ultrasound transducer immediately adjacent to the area of interest has allowed the use of higher frequencies, thus permitting greater spatial resolution. The ability to image the wall of the gastrointestinal tract as a series of definable layers corresponding to histology, rather than a single entity, results in a powerful clinical tool and is the basis of most of the indications for EUS. Other indications have emerged from the ability of EUS to provide detailed images of the areas in immediate proximity to the gastrointestinal tract and to guide needles precisely through the gut wall and surrounding structures. 18-32 Indications for EUS can be divided into 3 main categories: (1) submucosal abnormalities, (2) cancer staging, and (3) pancreatic biliary disease. EUS can make a difference in all of these clinical areas and can be performed with a low complication rate similar to diagnostic endoscopy. As an extension of imaging, several reports have described the use of endosonography in conjunction with needle aspiration biopsy to sample lesions within and adjacent to the gastrointestinal (GI) tract.18-32 The technique is also good in confirming suspected malignancy of pancreatic lesions and submucosal tumors. They also
From the Medical College of Wisconsin, St Lukes Medical Center, and Pancreatic Biliary Center, Milwaukee, WI. Address reprint requests to Marc F. Catarano, MD, FACG, FACP, 2801 Kinnickinnic River Pkwy #570, Milwaukee, W153215. Copyright 9 2000 by W.B. Saunders Company 1096-2883/00/0203-0007510.00/0 doi:10.1053/tgie.2000.7741
The relative high frequency of renal lesions, both cystic and solid, provides a potential new indication for endosonography. The proximity of the kidney to the GI tract, particularly the left, allows easy targeting of these lesions in question, including primary (renal cell carcinoma) and metastatic. Similarly, because of the intimate association of the adrenal glands, these structures can also be imaged and targeted for fine-needle aspiration. 3s Imaging. The left kidney is imaged using radial uhrasonography by advancing the echoendoscope to the gastric cardia where the abdominal aorta is noted in its transverse section and placed at the 6-o'clock position. Advancement along the greater curvature of the stomach initially brings into view the spleen, followed shortly by the left kidney and adrenal gland, along with the left renal vein and artery. Just proximal to the celiac axis, the left adrenal usually can be seen as an echolucent thin strip of tissue to the left of the aorta. It can appear as a long stripe or m a "seagull" shape. The adrenal cortex is generally more echolucent than the echogenic medullary portion. Adrenal adenomas are seen in 2% to 3% of normal patients and appear as ovoid or round homogenous masses occupying part of the adrenal gland. 3s Alternatively, the left kidney can be followed cephalad to view the left adrenal on the medial side of the upper pole. Deep advancement of the echoendoscope into the duodenum shows landmark structures, side-by-side cross section of the inferior vena cava and abdominal aorta. Small adjustments may allow visualization of the right kidney just lateral to these structures. After advancement of the linear echoendoscope in preparation for YNA, the abdominal aorta is used as a landmark structure. This is initially picked up at the level of the
Techniques in Gastrointestinal Endoscopy, Vol 2, No 3 (July), 2000: pp 159-164
159
Fig 1. CT scan showing a 6-cm mass anterior to left kidney,
gastroesophageal junction by rotating clockwise or counterclockwise. From this level, rotating slightly clockwise while advancing the instrument a few centimeters will enable the endosonographer to view both the left adrenal and accompanying kidney. This can be considerably more difficult to visualize than with radial technology. Even more challenging is the visualization of the right kidney and adrenal. This can be accomplished by advancing the linear array echoendoscope to the level of the ampulla. Retraction and slight rotation brings into view the portal vein and common bile duct. Further retraction and rotation can bring these 2 organs into view for FNA. Literature. The application of EUS in imaging the kidneys and the adrenal glands has been reported by Chang et al. 3s Thirty-one consecutive patients presenting with known malignancies of the lung or gastrointestinal tract were evaluated for metastasis to the adrenal glands. In 30 of 31 patients (97%), the left adrenal gland was fully characterized. EUS-guided FNA of the adrenal gland was performed in 1 patient with lung cancer suspected of having metastatic disease. Results showed malignant involvement of the left adrenal gland, thus avoiding operative resection.
Although imaging of the kidneys has been described in limited detail by few investigators, only 1 report has described EUS-guided FNA and diagnosis of renal tumors. Faigel et a139 reported a total of 23 extraluminal EUS-guided FNA cases. One patient had a known mass involving the left kidney. Although
Fig 2. EUS of patient in Figure I showing a mixed echogenic mass. EUS-guided FNA is performed.
Fig 4. EUS showing a 3-cm hypoechoic mass within to the left lobe of the liver.
160
Fig 3. Histology of EUS FNA of patient in Figures I and 2, showing a ganglioneuroma (provided by Richard A Erickson, MD).
MARC E CATALANO
TABLE 1. Results of EUS-Guided FNA of 34 Patients Presenting With Abdominal Masses
Disease Classification Infectious Benign/inflammatory Malignant Total
Fig 5. EUS FNA of patient in Figure 7.
cytology showed benign cells, long-term follow-up showed renal cell carcinoma. Both the left and right kidney can nonetheless be approached using EUS-guided FNA tissue sampling. In a study evaluating imaging of retroperitoneal organs by EUS in 604 consecutive patients, the left kidney was shown in 530 cases (88%) and the right kidney in 554 (90%) patients. 4~ In a multicenter report of 142 consecutive cases of non-GI EUS/ FNA, 7 patients had either renal (n = 4) or adrenal (n = 3) lesions 36 (Figs 1-3). Successful cytological sampling was reported in all 7 patients (100%), with all but 1 lesion showing benign disease (adrenal adenoma).
Ovaries~Uterus Female reproductive organs have shown increasing incidence of malignant disease, which frequently requires biopsy before definitive treatment. Endorectal ultrasonography allows for the close proximity imaging of these structures, particularly those of the left adnexa. Imaging. The examination of the rectum and surrounding structures, including uterus and adnexa, can best be imaged on withdrawal of the radial echoendoscope from the sigmoid
FNA Passes Patient Range No. (Mean) 5 6 23 34
1-4 (2.2) 2-4 (3.2) 2-9 (4.6) 1-9 (3.8)
EUS Dx Alters EUS FNA Diagnostic Workup Therapy n (%) n (%) n (%) 4 (80) 4 (67) 21 (91) 29 (85)
4 4 21 29
(80) (67) (91) (85)
4 (80) 3 (50) 19 (83) 26 (77)
colon. At this level, depending on the shape of the sigmoid colon, the left ovary occasionally can be seen. The uterus next appears between the rectum and the bladder, and because of the very dense muscular organ, it can occasionally be difficult to see beyond this structure. Further withdrawal brings into view the vagina, which appears anteriorly as a flattened, inverted, "U-shaped" structure with a thin bright stripe of air within it. Deep to the vagina, the cross-sectional urethra with its surrounding sphincter appears as a circular echolucent structure. Withdrawal of the linear echoendoscope from the sigmoid colon will bring the uterus into view, with the bladder located more deeply. Occasionally, the left adnexal structure also can be seen on deep insertion near the pelvic rim vessds. Further withdrawal from the level of the uterus will show a landmark structure view of the "air stripe" of the vaginal cavity anteriorly, with portions of the urethra seen deep to it. Literature. Very little is written in literature regarding EUS-guided FNA of female reproductive organs. 41 This is particularly related to the inability to image the right ovary and the less than optimal visualization of the left ovary. In a study previously addressed, only 2 of a 142 patients who presented with non-GI lesions underwent EUS-guided FNA (2 ovarian lesions).36 Both patients had a correct diagnosis established by EUS FNA.
Prostate Lesions of the prostate are quite common but infrequently present to the gastroenterologist. Under such a circumstance they often present with rectal symptoms (ie, pain or bleeding) from the extension of the lesion through the rectal wall. Endosonography in this instance could allow for the correct diagnosis and establish extent of the disease. Imaging. The radial echoprobe is advanced beyond the rectum into the sigmoid colon. When the echoprobe is withdrawn to 10 to 15 cm from the anal verge, the seminal vesicles appear initially as a pair of echolucent ovoid structures anterior to the rectum. On further withdrawal, the right and left seminal vesicles merge into a single longitudinal structure
TABLE 2. Results of EUS-Guided FNA of 26 Patients Presenting With Mediastinal Masses
Disease Classification
Fig 6. Histology of patient in Figures 7 and 8 showing metastatic adenocarcinoma. EUS-GUIDED FNA IN ABDOMINAL MASSES
Infectious Benign/inflammatory Malignant Total
FNA Passes Patient Range No. (Mean) 5 9 12 26
1-5 (3.4) 2-3 (3.0) 1-7 (4.4) 1-7 (3.8)
EUS Dx Alters EUS RNA Diagnostic Workup Therapy (%) (%) (%) 3 (60) 7 (78) 11 (92) 21 (81)
3 (60) 6 (67) 11 (92) 20 (77)
3 (60) 7 (78) 9 (75) 19 (73) 1 61
Fig 9. Histology of patient in Figures 7 and 8 showing adenocarcinoma.
Liver Fig 7. EUS showing a 4.2-cm mediastinal mass adjacent to the esophagus at 25 cm.
between the rectum and bladder. With the probe further retracted, the prostate can be seen as a semicircular structure in the anterior perirectal region. On linear imaging, the probe is again placed to the left of the sigmoid colon and slowly withdrawn to 7 to 12 cm. Here, rotation to the right or left will bring into view the prostate. Just proximal to the prostate, one can view the seminal vesicle. Literature. In the only report of EUS-guided FNA of the prostate, 4 patients presented with prostatic lesions, with invasion of adjacent structures in 3 of the patients (75%). 36 These were successfully imaged and biopsies were performed, with an accurate diagnosis achieved in all patients (100%), including 3 malignant and 1 benign lesion.
Fig 8. EUS FNA of patient in Figure 7. 162
The liver represents the organ most commonly affected by metastatic disease. In addition, numerous primary malignant and benign lesions of the liver are described. Occasionally, metastatic lesions of the liver are not identified preoperatively in patients with primary malignancy elsewhere and are noted either intraoperatively or at intervals postoperatively. Endosonography, until recently, has not traditionally been thought to be applicable in the detection or evaluation of existing liver metastasis (Figs 4-6). Imaging. On entering the abdomen with the radial echoendoscope, the left lobe of the liver dominates the view. Near the hiatus, the hepatic veins are seen draining into the inferior vena cava. The remaining left lobe of the liver and parts of the right lobe can be visualized by advancing the probe down the lesser curvature of the stomach toward the antrum. The liver hilum can be examined by placing the probe within the duodenum and slowly retracting toward the duodenum with upward tip deflection.
Fig 10. EUS depicting a 4-cm mediastinal mass in a patient presenting with dysphagia and chest pain, MARC E CATALANO
Literature. In a prospective study, Nguyen et a143 evaluated 574 consecutive patients for liver metastasis with a history or suspicion of GI or pulmonary malignant tumors by EUS. Fourteen (2.4%) were found to have 15 focal liver lesions and underwent EUS-guided FNA. The median largest diameter of the liver lesion was 1.1 cm. All FNA samples yielded adequate specimens. Fourteen of 15 lesions aspirated were malignant. Only 3 of 14 patients had demonstrable lesions on computed tomography (CT) scan.
Intra-abdominal Mass--Nongastrointestinal Intra-abdominal masses from specific organs are occasionally encountered, including malignant disease (lymphoma, sarcoma) and benign lesions (leiomyoma, abscess). The role of EUS-guided FNA to establish diagnosis of such idiopathic abdominal masses has not been previously described. In a recent muhicenter study, 42 34 patients underwent EUS-guided FNA in patients with idiopathic abdominal masses at 5 tertiary centers. Four of 34 patients had history of intra-abdominal cancers (cervical = 2, ovarian cancer = 1, colon cancer = 1). Final diagnosis using EUS FNA, surgery, autopsy, or long-term follow-up was available in all patients (Table 1). EUS FNA results were classified under 3 disease categories: infectious, benign/inflammatory, and malignant. Final diagnosis included infectious (n = 5), benign/inflammatory (n = 6), and malignant abdominal (n = 23). EUS-guided FNA was successful in establishing a tissue diagnosis in 29 of 34 patients (85%) for all 3 categories. EUS-guided FNA was successful in directing subsequent workup in 85% and subsequent therapy in 77% of patients.
Idiopathic Mediastinal Masses Mediastinal masses occasionally present a diagnostic challenge. Methods of tissue sampling have traditionally included mediastinoscopy and bronchoscopy with varying efficacy. A more reliable method of evaluation, including tissue sampling,
Fig 12. Histology of patient in Figures 10 and 11 showing large cell lymphoma.
may be EUS-guided FNA. The role of EUS-guided FNA to establish the diagnosis of idiopathic mediastinal masses has been limited. 34,35,44 In a recent study by Catalano et al, 37 26 patients, including 15 men and 1l women (age range 39-77; mean, 61) underwent EUS-guided FNA in patients with idiopathic mediastinal masses at 4 tertiary referral centers (Table 2). Presenting symptoms included chest pain = 10, dysphagia = 8, cough = 7, fever = 6, night sweats = 3, and no symptoms/abnormal radiograph = 5. Five of 26 patients had history of cancer (3 lung, 1 tracheal, and 1 esophageal). Final diagnosis using EUS FNA, surgery, autopsy, and other diagnostic study or long-term follow-up was available in all patients. EUS FNA results were classified under 3 disease categories: infectious, benign/ inflammatory, and malignant. Follow-up diagnosis included infectious = 5, benign/inflammatory -- 9, malignant = 12 (Figs 7-12). EUS-guided FNA was successful in 21 of 26 patients (81%) for all disease categories (infectious, 60%; benign/inflammatory, 78%; and malignant, 92%). EUS FNA was successful in directing subsequent workup in 77% (20 of 26) and therapy in 73% (19 of 26). EUS-guided FNA passes for adequate tissue sampling was lower for nonmalignant disease categories (3.0 to 3.4) versus malignant disease (4.4). No complications were seen during the course of the study. In conclusion, EUS-guided FNA in idiopathic abdominal and mediastinal masses as well as a variety of miscellaneous non-GI lesions provides excellent imaging and diagnostic accuracy in most patients. These results assist in guiding subsequent therapy and establishing prognosis in these patients.
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Fig 11. EUS FNAof patient in Figure 10. EUS-GUIDED FNA IN ABDOMINAL MASSES
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MARC F. CATALANO