Improved Technique for Performing Endoscopic Ultrasound Guided Fine Needle Aspiration of Lymph Nodes

Background and Study Aims: Trans-esophageal real-time endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) has emerged as an important technique for sampling perigastrointestinal lymph nodes. The purpose of this study was to compare the yield of EUS-guided FNA of mediastinal lymph nodes using different techniques.

Materials and Methods: A 2 cm mediastinal lymph node was dissected at autopsy. FNA was performed on this lymph node with a 21 gauge needle which is used clinically for EUS-guided FNA (GIP-Mediglobe). FNA of the lymph node was performed for 60 sec, while continuous or intermittent suction was applied with a 10 ml, 20 ml and 30 ml syringe. The pathologist was blinded to the technique used for FNA of the lymph node. The slides were examined and the results recorded independently by two pathologists who were blinded to each other's findings. A similar procedure was repeated in a 2 cm lymph node removed during another autopsy.

Results: Pathologic examination revealed metastatic transitional cell bladder carcinoma in the first lymph node, and metastatic non-small cell lung carcinoma in the second lymph node. The cellularity and quality of FNA performed with the 10 ml syringe was better than with the 20 ml or 30 ml syringe. With the 10 ml syringe, continuous suction for one minute provided a better sample than intermittent suction. FNA with a 20 ml or 30 ml syringe was more cumbersome, as it required more physical force.

Conclusions: Our study reveals that continuous rather than intermittent suction with smaller syringes (5 - 10 ml) provides optimal cellularity in EUS-guided FNA of mediastinal lymph nodes and that use of larger (20 - 30 ml) syringes does not improve the rate of obtaining a diagnostic specimen.

References

• 1 Bhutani M S, Hawes R H, Hoffman B J. A comparison 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. 1997;  45 474-479
• 2 Bhutani M, Hoffman B, Reed C, et al. Lymph node staging of esophageal and non-small cell lung cancer by endoscopic ultrasound-guided fine-needle aspiration cytology (Abstract).  Gastrointest Endosc. 1995;  41 299
• 3 Gress F, Savides T J, Sandler A, et al. Endoscopic ultrasonography, fine-needle aspiration guided by endoscopic ultrasonography, and computed tomography in the preoperative staging of non-small cell lung cancer: A comparison study.  Ann Intern Med. 1997;  127 604-616
• 4 Silvestri G A, Hoffman B J, Bhutani M S, et al. Endoscopic ultrasound with fine-needle aspiration in the diagnosis and staging of lung cancer.  Ann Thorac Surg. 1996;  61 1441-1446
• 5 Bhutani M S. Pros and cons of endoscopic ultrasound-guided access to the mediastinum in patients with lung cancer.  Adv Gastroenterol Hepatol Nutr. 1988;  3 59-62
• 6 Catalano M F, Sivak M V, Rice T, et al. Endosonographic features predictive of lymph node metastases.  Gastrointest Endosc. 1994;  40 442-446
• 7 Akahoski K, Misawa T, Fujishima H, et al. Regional lymph node metastasis in gastric cancer. Evaluation with endoscopic US.  Radiology. 1992;  182 559-564
• 8 Vassalo P, Edel G, Roos N, et al. In vitro high-resolution ultrasonography of benign and malignant lymph nodes.  Invest Radiol. 1993;  28 698-705
• 9 Heintz A, Mildenberger P, Georg M, et al. Endoscopic ultrasonography in the diagnosis of regional lymph nodes in esophageal and gastric cancer. Results of studies in vitro.  Endoscopy. 1993;  25 231-235
• 10 Tio T L, Tytgat G NJ. Endoscopic ultrasonography in analyzing peri-intestinal lymph node abnormality.  Scand J Gastroenterol. 1986;  21 (Suppl. 123) 158-163
• 11 Grimm H, Hamper K, Binmoeller K F, Soehendra N. Enlarged lymph nodes; malignant or not?.  Endoscopy. 1992;  24 (Suppl. 1) 320-323
• 12 Sugimachi K, Ohno S, Fujishima H, et al. Endoscopic ultrasonographic detection of carcinomatous invasion and of lymph nodes in the thoracic esophagus.  Surgery. 1990;  107 366-370