Endoscopic diagnosis of early squamous neoplasia of the esophagus with iodine staining: high-grade intra-epithelial neoplasia turns pink within a few minutes.
OBJECTIVE
The ability to detect early squamous neoplasia of the esophagus can be enhanced considerably by iodine staining during endoscopic examination; however, there has been no study on distinguishing high-grade intra-epithelial squamous neoplasia from low-grade dysplasia by endoscopic examination. We assumed that high-grade intra-epithelial neoplasia could be identified as iodine-unstained areas more distinct and reddish than low-grade dysplasia after the brown color of iodine solution has faded, because there is almost no remaining glycogen-containing epithelium in high-grade intra-epithelial neoplasia.


METHODS
Seventy-nine patients who were found to have demarcated iodine-unstained areas (0.5 cm to 1.5 cm at widest part, 121 lesions in total) were studied. After a target lesion was found, the lesion was observed for about 3 min and its discoloration was evaluated. If a light-pink part appeared in the iodine-unstained area, the lesion was regarded as being positive for pink color. If no light-pink part was observed in the lesion within 3 min, the lesion was regarded as being negative for pink color.


RESULTS
Thirty-four (87.2%) of the 39 lesions diagnosed as pink-color positive were histologically confirmed to be high-grade intra-epithelial squamous neoplasia or squamous cell carcinoma, whereas only three (3.7%) of the 82 lesions diagnosed as negative for pink color were histologically confirmed to be high-grade intra-epithelial squamous neoplasia (P < 0.0001). Using the pink-color sign as a diagnostic index for high-grade intra-epithelial squamous neoplasia and squamous cell carcinoma, sensitivity was 91.9% and specificity was 94.0%.


CONCLUSIONS
By using the pink-color sign for endoscopic diagnosis, accurate diagnosis without endoscopic biopsy for iodine-unstained areas was possible.
Shimizu
Yuichi
Y
Division of Endoscopy, Hokkaido University Hospital, Sapporo, Japan. yshimizu@med.hokudai.ac.jp
Omori
Tai
T
Yokoyama
Akira
A
Yoshida
Takeshi
T
Hirota
Jojo
J
Ono
Yuji
Y
Yamamoto
Junji
J
Kato
Mototsugu
M
Asaka
Masahiro
M
D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D004938:Esophageal Neoplasms / Q000473:pathology*; D004945:Esophagoscopy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013194:Staining and Labeling; D013997:Time Factors