- Email: [email protected]
Real-time endoscopic ultrasound–guided fine-needle aspiration of a mediastinal lymph node
1. 2.
3. 4.
5. 6. 7. 8. 9. 10. 11. 12. 13.
REFERENCES Mucha P Jr. Small intestinal obstruction. Surg Clin North Am 1987;67:587-620. Bizer LS, Liebling RW, Delaney HM, Gliedman ML. Small bowel obstruction: the role of nonoperative treatment in simple intestinal obstruction and predictive criteria for strangulation obstruction. Surgery 1981;89:407-13. Hofstetter SR. Acute adhesive obstruction of the small intestine. Surg Gynecol Obstet 1981;152:141-4. Wolfson PJ, Bauer JJ, Gelernt TM, Kreel I, Aufses AH Jr. Use of the long tube in the management of patients with small-intestinal obstruction due to adhesions. Arch Surg 1985;120: 1001-6. Helmkamp BF, Kimmer J. Conservative management of small bowel obstruction. Am J Obstet Gynecol 1985;152:677-9. Ellis H. The causes and prevention of intestinal adhesions. Br J Surg 1982;69:241-3. Weibel MA, Majno G. Peritoneal adhesions and their relation to abdominal surgery. Am J Surg 1973;126:345-53. Ellis H. The aetiology of postoperative abdominal adhesions. Br J Surg 1962;50:10-16. Ellis H. Internal overhealing: the problem of intraperitoneal adhesions. World J Surg 1980;4:303-6. Sarr MG, Bulkley GB, Zuidema GD. Preoperative recognition of intestinal strangulation obstruction: prospective evaluation of diagnostic capability. Am J Surg 1983;145:176-82. Weigelt JA, Snyder WH III, Norman JL. Complications and results of 160 Baker tube plications. Am J Surg 1980;140:810-5. Gowen GF, DeLaurentis DA, Stefan MM. Immediate endoscopic placement of long intestinal tube in partial obstruction of the small intestine. Surg Gynecol Obstet 1987;165:457-8. Zadeh BJ, Davis JM, Canizaro PC. Small bowel obstruction in the elderly. Am Surg 1985;51:470-3.
Real-time endoscopic ultrasound-guided fine-needle aspiration of a mediastinal lymph node Maurits J. Wiersema, Michael L. Kochman, Amitabh Chak, Harvey M. Cramer, Kenneth A. Kesler,
MD MD MD MD MD
Endoscopic ultrasonography (EUS) is an exciting new technique for imaging the wall of the gastrointes-
Received August 26,1992. For revision September 9,1992. Accepted October 22, 1992. From the Division of Gastroenterology/Hepatology, Department of Medicine, the Division of Cytopathology, Department of Pathology, and the Division of Cardiovascular and Thoracic Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana. Reprint requests: Maurits J. Wiersema, MD, Indiana University Hospital, Room 2300, 550 N. University Blvd., Indianapolis, IN 46202. 0016-5107/93/3903-0429$1.00 + .10 GASTR01NTESTINALENDOSCOPY Copyright 1993 by the American Society for Gastrointestinal Endoscopy
37/69/43904
VOLUME 39, NO.3, 1993
14. Shatilla AH, Chamberlain BE, Gleff WR. Current status of diagnosis and management of strangulation obstruction of small bowel. Am J Surg 1976;132:299-303. 15. Hegedus V, Poulsen PE, Mohammed SH. Management of obstructive small-bowel lesions. Acta Chir Scand 1988;154:517-20. 16. Nealon WH, Beachame RD, Halpert R, Thompson JC. Combined endoscopic and fluoroscopic balloon dilatation of a complex proximal jejunal stricture. Surgery 1989;105:113-6. 17. Bedogni G, Ricci E, Pedrazzoli C, et al. Endoscopic dilation of anastomotic colonic stenosis by different techniques: an alternative to surgery? Gastrointest Endosc 1987;33:21-6. 18. Brower RA. Hydrostatic balloon dilation of a terminal ileal stricture secondary to Crohn's disease. Gastrointest Endosc 1986;32:38-40. 19. Ball WS Jr, Kosloske AM, Jewell PF, Seigel RS, Bartow SA. Balloon catheter dilatation of focal intestinal strictures following necrotizing enterocolitis. J Pediatr Surg 1985;20:637-9. 20. Canady J, Jamil Z, Wilson J, Bernard LJ. Intestinal obstruction: still a lethal clinical entity. J Natl Med Assoc 1987;79:1281-4. 21. Cheadle WG, Garr EE, Richardson JD. The importance of early diagnosis of small bowel obstruction. Am Surg 1988;54:565-9. 22. Playforth RH, Halloway JB, Griffen WO Jr. Mechanical small bowel obstruction: a plea for earlier surgical intervention. Ann Surg 1970;171:783-8. 23. Peetz DJ, Gamelli RL, Pilcher DB. Intestinal intubation in acute, mechanical small-bowel obstruction. Arch Surg 1982;117: 334-6. 24. Cotton PB, Williams CB. Practical gastrointestinal endoscopy. 3rd ed. Boston: Blackwell Scientific Publications, 1990: 160-223.
tinal tract and adjacent tissues. The technique has been proved to have superior accuracy when compared with CT scanning for TNM staging of esophageal and gastric cancer. 1-3 EUS is not equivalent to histologic examination, however, and tissue sampling is still required for the confirmation of findings. Problems may arise when lesions are not amenable to standard biopsy techniques. EUS has been used to locate lymph nodes and extrinsic masses adjacent to the UGI tract, which may then be evaluated with fine-needle aspiration (FNA) cytologic sampling by way of a standard gastroscope. 4 This technique, however, does not have the ability to directly visualize the entry of the needle into the area of interest by ultrasonography. Recently, a case has been reported describing the use of EUS to guide FNA of a cystic neoplasm arising within the pancreatic head. 5 We present the case of a patient with lung cancer and malignant mediastinallymphadenopathy diagnosed by real-time EUS-guided FNA. CASE REPORT AND METHOD
A 64-year-old man with a history of heavy tobacco use presented with anorexia and a I5-pound weight loss during the previous month. The patient denied symptoms of dysphagia. A chest x-ray film demonstrated a 3-cm mass in the right upper lobe. Discrete widening of the mediastinum was not noted. On CT scan the lesion in the right upper lobe 429
Figure 1. Ultrasound image from distal esophagus obtained with Olympus GF-UM3 probe (12 MHz) showing hypoechoic mediastinal lymph node (In) measuring up to 2.5 cm in greatest dimension. Adjacent hyperechoic benignappearing lymph node is seen (arrow). ao, Aorta; az, azygos vein; s, spine.
Figure 2. Pentax/Hitachi FG-32UA ultrasound endoscope with prototype Wilson-Cook catheter exiting from biopsy channel. Needle is extended from sheath and lies in imaging plane of transducer.
was seen, as well as borderline enlargement of periesophageallymph nodes in the posterior mediastinum. FNA cytonon-logic sampling of the primary lesion showed that it was a non-small-cell carcinoma. However, the periesophageal lymph nodes in question were not readily accessible by mediastinoscopy, transbronchial biopsy, or percutaneous routes, and therefore an alternative method of sampling was sought. The patient was referred for EUS with possible transesophageal FNA. Initial screening endoscopy before EUS did not demonstrate any evidence ofluminal compromise in the esophagus. Endosonography was performed with the Olympus GF-UM3 instrument, a mechanical 360-degree radial scanning instrument that operates at both 7.5 and 12 MHz (Olympus Corp. Lake Success, N.Y.). A 2.5-cm hypoechoic lymph node was seen in the periesophageal space along the right anterior 430
Figure 3. Ultrasound image from distal esophagus obtained with Pentax/Hitachi probe (7.5 MHz) illustrating hypoechoic lymph node (In) with echogenic needle (arrows) coursing through lesion. Arrowhead, needle tip; e, esophageal wall.
margin below the level of the left atrium (Fig. 1). With use of the measurement and position information obtained during the ultrasound exam, a forward-viewing gastroscope in conjunction with a transbronchial aspiration needle (STIFCORE transbronchial aspiration needle 1140, 20gauge, 13-mm long, working length 150 cm and sheath outside diameter of 1.8 mm; Microvasive, Watertown, Mass.) was used in an attempt to sample this lymph node. After three passes the attendant cytopathologist indicated that adequate material was not present. The Pentax/Hitachi FG-32UA ultrasound endoscope was then used to scan the lesion (Pentax Precision Instruments, Orangeburg, N.Y.). This instrument has a 100-degree linear convex array on the tip that allows ultrasound scanning parallel to the long axis of the endoscope. A 2-mm-diameter biopsy channel permits passage of accessories into the scan plane of the instrument (Fig. 2). Imaging demonstrated a hypoechoic periesophageal lymph node in the right anterior space. Under EUS visualization a prototype FNA catheter (25 gauge, 40-mm long, working length 180 cm and sheath outside diameter 5F; Wilson-Cook, Winston-Salem, N.C.) was advanced into the lymph node (Fig. 3). A lO-ml syringe was used to apply suction to the needle while the endoscopist made small to-andfro needle movements within the lymph node. The entire assembly was withdrawn, and the specimen sprayed on glass slides for Romanovsky staining. Two passes were made, and diagnostic material was obtained from each pass (Fig. 4). No complications were experienced, and the patient was referred for radiation therapy.
DISCUSSION
This is the first reported case describing fine-needle sampling of a periesophageal lymph node under realtime EUS guidance. We have previously shown that GASTROINTESTINAL ENDOSCOPY
.
•
•
'4;
J.
'.
Figure 4. Cohesive group of malignant epithelial cells diagnostic of poorly differentiated non-small cell carcinoma obtained from mediastinal lymph node (Papanicolaou stain, original magnification X400).
this can be accomplished indirectly by relying on anatomic information obtained at EUS. One would expect that the ability to visualize the needle with real-time ultrasonography would improve safety and yield. Additionally, performing the ultrasonography and FNA with the same instrument should enhance the efficiency of these exams. The Pentax/Hitachi probe allows the appropriate orientation for advancement of the aspirating needle into the scan plane of the transducer during cytologic sampling. These aspirating needles must have some flexibility to allow passage through the biopsy channel and additionally must be of a sufficient length to allow extension into the deeper peri-esophageal space. The length of this prototype needle permits sampling of structures within 2 cm ofthe surface ofthe gastrointestinal wall. The relatively small diameter of the needle, which is comparable to that used for percutaneous cytologic aspiration, did not present a problem because both passes in this case produced diagnostic tissue. The failure of our initial cytologic aspirates suggests the limitation of performing this technique under only endoscopic visual guidance with shorter needles (despite the larger needle gauge). The Olympus probe does not permit advancement of this 4-cm-Iong aspirating needle through the biopsy channel. Additionally, the orientation of the biopsy channel to the rotating transducer would not allow
VOLUME 39, NO.3, 1993
placement of the needle into the imaging plane. Collectively, these limitations preclude real-time ultrasound-guided FNA cytologic sampling from within the gastrointestinal tract with this type of equipment. The design of this aspirating catheter was influenced by the need to apply sufficient force as the needle tip traverses lesions that provide significant resistance to passage. The additional resistance from the endoscope channel and the internal sheath have to a great extent limited our success with prototypes that use a plastic catheter with a needle tip. The current prototype uses a needle that extends throughout the entire length of the sheath, and therefore a significantly greater force may be applied as the needle is advanced. The future applications and safety of this technique require additional study. A more definitive answer may now possibly be provided in regard to resectability of esophageal carcinoma if deep lymph nodes can be sampled efficiently. Additionally, as in this case of lung cancer, EUS-directed FNA precluded the need for surgical staging. We believe this technique will prove to have high diagnostic accuracy in sampling peri-esophageal and subcarinal lymph nodes, which will have important therapeutic implications in the treatment of esophageal carcinoma and non-small cell carcinoma of the lung. The potential cost savings as a result of this technique may be abundant in redirecting patients to non-surgical treatments when aggressive disease has been defined. Endoscopists now have an ultrasound device that may be combined with a needle-aspirating catheter to permit sampIing of mediastinallymph nodes. REFERENCES 1. Botet JF, Lightdale CJ, Zauber AG, Gerdes H, Urmacher C,
2. 3. 4.
5.
Brennan MF. Preoperative staging of esophageal cancer: comparison of endoscopic US and dynamic CT. Radiology 1991; 181:419-25. Tio TL, Lohen P, Coene P, Udding J, den Hartug Jager FCA, Tytgat GNJ. Endosonography and computed tomography of esophageal carcinoma. Gastroenterology 1989;96:1478-86. Botet JF, Lightdale CJ, Zauber AG, et al. Preoperative staging of gastric cancer: comparison of endoscopic US and dynamic CT. Radiology 1991;181:426-32. Wiersema MJ, Hawes RH, Tao L-C, et al. Endoscopic ultrasonography as an adjunct to fine needle aspiration cytology of the upper and lower gastrointestinal tract. Gastrointest Endosc 1992;38:35-9. Vilmann P, Jacobsen GK, Henriksen FW, Hancke S. Endoscopic ultrasonography with guided fine needle aspiration biopsy in pancreatic disease. Gastrointest Endosc 1991;38: 172-3.
431
3. 4.
5. 6. 7. 8. 9. 10. 11. 12. 13.
REFERENCES Mucha P Jr. Small intestinal obstruction. Surg Clin North Am 1987;67:587-620. Bizer LS, Liebling RW, Delaney HM, Gliedman ML. Small bowel obstruction: the role of nonoperative treatment in simple intestinal obstruction and predictive criteria for strangulation obstruction. Surgery 1981;89:407-13. Hofstetter SR. Acute adhesive obstruction of the small intestine. Surg Gynecol Obstet 1981;152:141-4. Wolfson PJ, Bauer JJ, Gelernt TM, Kreel I, Aufses AH Jr. Use of the long tube in the management of patients with small-intestinal obstruction due to adhesions. Arch Surg 1985;120: 1001-6. Helmkamp BF, Kimmer J. Conservative management of small bowel obstruction. Am J Obstet Gynecol 1985;152:677-9. Ellis H. The causes and prevention of intestinal adhesions. Br J Surg 1982;69:241-3. Weibel MA, Majno G. Peritoneal adhesions and their relation to abdominal surgery. Am J Surg 1973;126:345-53. Ellis H. The aetiology of postoperative abdominal adhesions. Br J Surg 1962;50:10-16. Ellis H. Internal overhealing: the problem of intraperitoneal adhesions. World J Surg 1980;4:303-6. Sarr MG, Bulkley GB, Zuidema GD. Preoperative recognition of intestinal strangulation obstruction: prospective evaluation of diagnostic capability. Am J Surg 1983;145:176-82. Weigelt JA, Snyder WH III, Norman JL. Complications and results of 160 Baker tube plications. Am J Surg 1980;140:810-5. Gowen GF, DeLaurentis DA, Stefan MM. Immediate endoscopic placement of long intestinal tube in partial obstruction of the small intestine. Surg Gynecol Obstet 1987;165:457-8. Zadeh BJ, Davis JM, Canizaro PC. Small bowel obstruction in the elderly. Am Surg 1985;51:470-3.
Real-time endoscopic ultrasound-guided fine-needle aspiration of a mediastinal lymph node Maurits J. Wiersema, Michael L. Kochman, Amitabh Chak, Harvey M. Cramer, Kenneth A. Kesler,
MD MD MD MD MD
Endoscopic ultrasonography (EUS) is an exciting new technique for imaging the wall of the gastrointes-
Received August 26,1992. For revision September 9,1992. Accepted October 22, 1992. From the Division of Gastroenterology/Hepatology, Department of Medicine, the Division of Cytopathology, Department of Pathology, and the Division of Cardiovascular and Thoracic Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana. Reprint requests: Maurits J. Wiersema, MD, Indiana University Hospital, Room 2300, 550 N. University Blvd., Indianapolis, IN 46202. 0016-5107/93/3903-0429$1.00 + .10 GASTR01NTESTINALENDOSCOPY Copyright 1993 by the American Society for Gastrointestinal Endoscopy
37/69/43904
VOLUME 39, NO.3, 1993
14. Shatilla AH, Chamberlain BE, Gleff WR. Current status of diagnosis and management of strangulation obstruction of small bowel. Am J Surg 1976;132:299-303. 15. Hegedus V, Poulsen PE, Mohammed SH. Management of obstructive small-bowel lesions. Acta Chir Scand 1988;154:517-20. 16. Nealon WH, Beachame RD, Halpert R, Thompson JC. Combined endoscopic and fluoroscopic balloon dilatation of a complex proximal jejunal stricture. Surgery 1989;105:113-6. 17. Bedogni G, Ricci E, Pedrazzoli C, et al. Endoscopic dilation of anastomotic colonic stenosis by different techniques: an alternative to surgery? Gastrointest Endosc 1987;33:21-6. 18. Brower RA. Hydrostatic balloon dilation of a terminal ileal stricture secondary to Crohn's disease. Gastrointest Endosc 1986;32:38-40. 19. Ball WS Jr, Kosloske AM, Jewell PF, Seigel RS, Bartow SA. Balloon catheter dilatation of focal intestinal strictures following necrotizing enterocolitis. J Pediatr Surg 1985;20:637-9. 20. Canady J, Jamil Z, Wilson J, Bernard LJ. Intestinal obstruction: still a lethal clinical entity. J Natl Med Assoc 1987;79:1281-4. 21. Cheadle WG, Garr EE, Richardson JD. The importance of early diagnosis of small bowel obstruction. Am Surg 1988;54:565-9. 22. Playforth RH, Halloway JB, Griffen WO Jr. Mechanical small bowel obstruction: a plea for earlier surgical intervention. Ann Surg 1970;171:783-8. 23. Peetz DJ, Gamelli RL, Pilcher DB. Intestinal intubation in acute, mechanical small-bowel obstruction. Arch Surg 1982;117: 334-6. 24. Cotton PB, Williams CB. Practical gastrointestinal endoscopy. 3rd ed. Boston: Blackwell Scientific Publications, 1990: 160-223.
tinal tract and adjacent tissues. The technique has been proved to have superior accuracy when compared with CT scanning for TNM staging of esophageal and gastric cancer. 1-3 EUS is not equivalent to histologic examination, however, and tissue sampling is still required for the confirmation of findings. Problems may arise when lesions are not amenable to standard biopsy techniques. EUS has been used to locate lymph nodes and extrinsic masses adjacent to the UGI tract, which may then be evaluated with fine-needle aspiration (FNA) cytologic sampling by way of a standard gastroscope. 4 This technique, however, does not have the ability to directly visualize the entry of the needle into the area of interest by ultrasonography. Recently, a case has been reported describing the use of EUS to guide FNA of a cystic neoplasm arising within the pancreatic head. 5 We present the case of a patient with lung cancer and malignant mediastinallymphadenopathy diagnosed by real-time EUS-guided FNA. CASE REPORT AND METHOD
A 64-year-old man with a history of heavy tobacco use presented with anorexia and a I5-pound weight loss during the previous month. The patient denied symptoms of dysphagia. A chest x-ray film demonstrated a 3-cm mass in the right upper lobe. Discrete widening of the mediastinum was not noted. On CT scan the lesion in the right upper lobe 429
Figure 1. Ultrasound image from distal esophagus obtained with Olympus GF-UM3 probe (12 MHz) showing hypoechoic mediastinal lymph node (In) measuring up to 2.5 cm in greatest dimension. Adjacent hyperechoic benignappearing lymph node is seen (arrow). ao, Aorta; az, azygos vein; s, spine.
Figure 2. Pentax/Hitachi FG-32UA ultrasound endoscope with prototype Wilson-Cook catheter exiting from biopsy channel. Needle is extended from sheath and lies in imaging plane of transducer.
was seen, as well as borderline enlargement of periesophageallymph nodes in the posterior mediastinum. FNA cytonon-logic sampling of the primary lesion showed that it was a non-small-cell carcinoma. However, the periesophageal lymph nodes in question were not readily accessible by mediastinoscopy, transbronchial biopsy, or percutaneous routes, and therefore an alternative method of sampling was sought. The patient was referred for EUS with possible transesophageal FNA. Initial screening endoscopy before EUS did not demonstrate any evidence ofluminal compromise in the esophagus. Endosonography was performed with the Olympus GF-UM3 instrument, a mechanical 360-degree radial scanning instrument that operates at both 7.5 and 12 MHz (Olympus Corp. Lake Success, N.Y.). A 2.5-cm hypoechoic lymph node was seen in the periesophageal space along the right anterior 430
Figure 3. Ultrasound image from distal esophagus obtained with Pentax/Hitachi probe (7.5 MHz) illustrating hypoechoic lymph node (In) with echogenic needle (arrows) coursing through lesion. Arrowhead, needle tip; e, esophageal wall.
margin below the level of the left atrium (Fig. 1). With use of the measurement and position information obtained during the ultrasound exam, a forward-viewing gastroscope in conjunction with a transbronchial aspiration needle (STIFCORE transbronchial aspiration needle 1140, 20gauge, 13-mm long, working length 150 cm and sheath outside diameter of 1.8 mm; Microvasive, Watertown, Mass.) was used in an attempt to sample this lymph node. After three passes the attendant cytopathologist indicated that adequate material was not present. The Pentax/Hitachi FG-32UA ultrasound endoscope was then used to scan the lesion (Pentax Precision Instruments, Orangeburg, N.Y.). This instrument has a 100-degree linear convex array on the tip that allows ultrasound scanning parallel to the long axis of the endoscope. A 2-mm-diameter biopsy channel permits passage of accessories into the scan plane of the instrument (Fig. 2). Imaging demonstrated a hypoechoic periesophageal lymph node in the right anterior space. Under EUS visualization a prototype FNA catheter (25 gauge, 40-mm long, working length 180 cm and sheath outside diameter 5F; Wilson-Cook, Winston-Salem, N.C.) was advanced into the lymph node (Fig. 3). A lO-ml syringe was used to apply suction to the needle while the endoscopist made small to-andfro needle movements within the lymph node. The entire assembly was withdrawn, and the specimen sprayed on glass slides for Romanovsky staining. Two passes were made, and diagnostic material was obtained from each pass (Fig. 4). No complications were experienced, and the patient was referred for radiation therapy.
DISCUSSION
This is the first reported case describing fine-needle sampling of a periesophageal lymph node under realtime EUS guidance. We have previously shown that GASTROINTESTINAL ENDOSCOPY
.
•
•
'4;
J.
'.
Figure 4. Cohesive group of malignant epithelial cells diagnostic of poorly differentiated non-small cell carcinoma obtained from mediastinal lymph node (Papanicolaou stain, original magnification X400).
this can be accomplished indirectly by relying on anatomic information obtained at EUS. One would expect that the ability to visualize the needle with real-time ultrasonography would improve safety and yield. Additionally, performing the ultrasonography and FNA with the same instrument should enhance the efficiency of these exams. The Pentax/Hitachi probe allows the appropriate orientation for advancement of the aspirating needle into the scan plane of the transducer during cytologic sampling. These aspirating needles must have some flexibility to allow passage through the biopsy channel and additionally must be of a sufficient length to allow extension into the deeper peri-esophageal space. The length of this prototype needle permits sampling of structures within 2 cm ofthe surface ofthe gastrointestinal wall. The relatively small diameter of the needle, which is comparable to that used for percutaneous cytologic aspiration, did not present a problem because both passes in this case produced diagnostic tissue. The failure of our initial cytologic aspirates suggests the limitation of performing this technique under only endoscopic visual guidance with shorter needles (despite the larger needle gauge). The Olympus probe does not permit advancement of this 4-cm-Iong aspirating needle through the biopsy channel. Additionally, the orientation of the biopsy channel to the rotating transducer would not allow
VOLUME 39, NO.3, 1993
placement of the needle into the imaging plane. Collectively, these limitations preclude real-time ultrasound-guided FNA cytologic sampling from within the gastrointestinal tract with this type of equipment. The design of this aspirating catheter was influenced by the need to apply sufficient force as the needle tip traverses lesions that provide significant resistance to passage. The additional resistance from the endoscope channel and the internal sheath have to a great extent limited our success with prototypes that use a plastic catheter with a needle tip. The current prototype uses a needle that extends throughout the entire length of the sheath, and therefore a significantly greater force may be applied as the needle is advanced. The future applications and safety of this technique require additional study. A more definitive answer may now possibly be provided in regard to resectability of esophageal carcinoma if deep lymph nodes can be sampled efficiently. Additionally, as in this case of lung cancer, EUS-directed FNA precluded the need for surgical staging. We believe this technique will prove to have high diagnostic accuracy in sampling peri-esophageal and subcarinal lymph nodes, which will have important therapeutic implications in the treatment of esophageal carcinoma and non-small cell carcinoma of the lung. The potential cost savings as a result of this technique may be abundant in redirecting patients to non-surgical treatments when aggressive disease has been defined. Endoscopists now have an ultrasound device that may be combined with a needle-aspirating catheter to permit sampIing of mediastinallymph nodes. REFERENCES 1. Botet JF, Lightdale CJ, Zauber AG, Gerdes H, Urmacher C,
2. 3. 4.
5.
Brennan MF. Preoperative staging of esophageal cancer: comparison of endoscopic US and dynamic CT. Radiology 1991; 181:419-25. Tio TL, Lohen P, Coene P, Udding J, den Hartug Jager FCA, Tytgat GNJ. Endosonography and computed tomography of esophageal carcinoma. Gastroenterology 1989;96:1478-86. Botet JF, Lightdale CJ, Zauber AG, et al. Preoperative staging of gastric cancer: comparison of endoscopic US and dynamic CT. Radiology 1991;181:426-32. Wiersema MJ, Hawes RH, Tao L-C, et al. Endoscopic ultrasonography as an adjunct to fine needle aspiration cytology of the upper and lower gastrointestinal tract. Gastrointest Endosc 1992;38:35-9. Vilmann P, Jacobsen GK, Henriksen FW, Hancke S. Endoscopic ultrasonography with guided fine needle aspiration biopsy in pancreatic disease. Gastrointest Endosc 1991;38: 172-3.
431