Endoscopic ultrasound-guided fine-needle aspiration biopsy for lymphadenopathy of unknown origin.
OBJECTIVE
The diagnosis of mediastinal and intra-abdominal lymphadenopathy is sometimes difficult, especially in patients who have no other primary lesions. Lymphoma is one of the main causes of this condition. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe and accurate diagnostic procedure for lesions surrounding the gastrointestinal tract. However, diagnosing lymphoma using the EUS-FNA technique remains a diagnostic challenge, due to limitations in the amount of material sampled. The aim of the present study was to evaluate the yield of EUS-FNA biopsy (EUS-FNAB) using a large-gauge needle in patients with mediastinal and intra-abdominal lymphadenopathy of unknown origin, especially in relation to subclassification of the lymphomas.


METHODS
Consecutive patients with mediastinal and intra-abdominal lymphadenopathy of unknown origin who were referred between October 2003 and March 2005 were enrolled in the study. EUS-FNAB was carried out using a 19-gauge needle, passing through the esophageal, gastric, and duodenal walls. Pathological diagnoses were made on the basis of histological findings, including immunopathological staining.


RESULTS
A total of 104 patients were included in the study. The locations of the lymph nodes were mediastinal in 50 patients, intra-abdominal in 48 patients, and both mediastinal and intra-abdominal in six patients. The diagnoses made using EUS-FNAB were lymphoma (n = 48), metastasis (n = 16), and benign/reactive (n = 40). The overall accuracy of EUS-FNAB for unknown lymphadenopathy was 98 %, and it was possible to classify the lymphomas in accordance with the World Health Organization classifications in 88 % of cases. No serious complications occurred with the procedure.


CONCLUSIONS
Open thoracic surgery, laparotomy, and other invasive diagnostic procedures such as mediastinoscopy and laparoscopy can now be avoided, as EUS-FNAB is potentially a safe and accurate tool for diagnosing unknown lymphadenopathy, including lymphoma.
Yasuda
I
I
First Department of Internal Medicine, Gifu University, Gifu, Japan. yasudaic@aol.com
Tsurumi
H
H
Omar
S
S
Iwashita
T
T
Kojima
Y
Y
Yamada
T
T
Sawada
M
M
Takami
T
T
Moriwaki
H
H
Soehendra
N
N
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle / Q000379:methods*; D019160:Endosonography; D005260:Female; D006801:Humans; D008206:Lymphatic Diseases / Q000175:diagnosis* / Q000209:etiology; D008223:Lymphoma / Q000175:diagnosis*; D016393:Lymphoma, B-Cell / Q000175:diagnosis; D016399:Lymphoma, T-Cell / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity