Preoperative diagnosis of gastrointestinal stromal tumor by endoscopic ultrasound-guided fine needle aspiration.
OBJECTIVE
To evaluate the role of endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) in the preoperative diagnosis of gastrointestinal stromal tumor (GIST).


METHODS
From September 2002 to June 2006, Fifty-three consecutive EUS-FNAs of GI tract subepithelial hypoechoic tumors with continuity to proper muscle layer suspected as GIST by standard EUS were evaluated prospectively. The reference standards for the final diagnosis were surgery (n = 31), or clinical follow-up (n=22). Additionally, immunophenotyping of specimens obtained by EUS-FNA and surgical resection specimens were compared.


RESULTS
In 2 cases puncture was not performed because of anatomical problems. The collection rate of adequate specimens from the GI tract subepithelial hypoechoic tumor with continuity to proper muscle layer was 82% (42/51). The diagnostic rate for the tumor less than 2 cm, 2 to 4 cm, and 4 cm or more were 71% (15/21), 86% (18/21), and 100% (9/9), respectively. In 29 surgically resected cases, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of EUS-FNA using immunohistochemical analysis of GIST were 100% (24/24), 80% (4/5), 96% (24/25), 100% (4/4), and 97% (28/29), respectively. No major complications were encountered.


CONCLUSIONS
EUS-FNA with immunohistochemical analysis is a safe and accurate method in the pretherapeutic diagnosis of GIST. It should be taken into consideration in decision making, especially in early diagnosis following minimal invasive surgery for GIST.
Akahoshi
Kazuya
K
Department of Gastroenterology, Aso Iizuka Hospital, 3-83 Yoshio town, Iizuka 820-8505, Japan. kakahoshi2@aol.com
Sumida
Yorinobu
Y
Matsui
Noriaki
N
Oya
Masafumi
M
Akinaga
Rie
R
Kubokawa
Masaru
M
Motomura
Yasuaki
Y
Honda
Kuniomi
K
Watanabe
Masayuki
M
Nagaie
Takashi
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle / Q000379:methods*; D019160:Endosonography / Q000379:methods*; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity