Prognostic value and interobserver agreement of endoscopic ultrasonography for superficial squamous cell carcinoma of the esophagus: a prospective study.
OBJECTIVE
Submucosal invasion of superficial esophageal cancer (SEC) is related to the prognosis. We prospectively analyzed outcomes of SEC in patients staged by endoscopic ultrasonography (EUS).


METHODS
We staged 31 endoscopically diagnosed SEC cases using a 20/15-MHz thin probe. The EUS tumor stage was classified as EUSM (limited within mucosa), EUS-SM (with submucosal invasion), or EUS-MP over (invading the muscularis propria or deeper). Lymph node metastasis and 2-yr survival were analyzed according to the EUS tumor stage in 29 squamous cell carcinoma cases. Interobserver agreement of the EUS stage was tested between the examiner and a blind reviewer.


RESULTS
Lymph node metastasis was significantly frequent in the EUS-SM group (8 of 18 cases [44.4%]) compared with the EUS-M group (1 of 10 cases [10%]) (p = 0.03). Patient survival at 2 yr after initial therapy was 72.2% in the EUS-SM group and 90% in the EUS-M group. Death from cancer was noted only in the EUS-SM group (three cases). The accuracy rates of EUS tumor staging were 74.1% by the examiner and 66.7% by the blind reviewer, with moderate interobserver agreement (kappa = 0.46).


CONCLUSIONS
Thin-probe EUS can classify SEC into two groups: the EUS-M group with excellent outcome and the EUS-SM group with a significant risk of lymph node metastasis.
Yanai
Hideo
H
Department of Gastroenterology and Hepatology, Yamaguchi University School of Medicine, Minamikogushi, Ube, Japan. h.yanai@po.cc.yamaguchi-u.ac.jp
Harada
Toshiya
T
Okamoto
Takeshi
T
Hirano
Atsuyoshi
A
Takeo
Naori
N
Yoshida
Tomoharu
T
Okita
Kiwamu
K
Kawano
Toyokazu
T
D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000473:pathology*; D019160:Endosonography; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging / Q000379:methods*; D015588:Observer Variation; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016019:Survival Analysis