Treatment for superficial esophageal cancer based on histological features and gross appearance

According to the depth of invasion, sixty-one superficial esophageal cancers (SECs) were subclassified as follows: intraepithelial cancer (ep), mucosal cancer invading to the lamina propria mucosa (lpm), or to the muscularis mucosa (mm), and submucosal cancer limited to the inner one-third of the submucosal layer (sm1), to the middle one-third (sm2), or invading into the outer one-third (sm3) to investigate the relationship between the depth of invasion and gross type classified according to the Guidelines of the Japanese Research Society for Esophageal Disease. Our results show that the SECs comprised of 9 ep cancers, 8 lpm, 6 mm, 6 sm1, 19 sm2 and 13 sm3, none of the ep or lpm cancers had either lymph node metastasis or recurrence and one-third of the mm and sml cancers had metastasis only in the mediastinal nodes. One-third of the sm2 and sm3 cancers, otherwise, revealed nodal involvement at surgery, and one-fourth of those recurred postoperatively. Recurrence in the cervical nodes was found in 9% of these cancers. All the SECs of the gross types including protruding type, slightly elevated type more than 2 cm in diameter and distinctly depressed type were submucosal cancers, whereas all the SECs showing the gross types including flat type and slightly elevated type less than 2 cm in diameter were ep or lpm cancers. Therefore, we concluded that for SEC evaluated as flat or slightly elevated type less than 2 cm in diameter by the endoscopic examination, less radical treatment such as endoscopic mucosal resection (EMR) should be performed at first.