Barrett食道癌と食道・胃接合部癌の時代的変遷とH. pylori感染

Yearly Trends of Adenocarcinoma of the Esophago-gastric Junction and Barrett's Adenocarcinoma, and Association with Helicobacter pylori Infection

要旨　Barrett食道（BE）癌および食道・胃接合部（EGJ）癌を年代別に解析した．進行食道癌におけるBE癌の頻度は1990年代から2000年代で0.5％から2.8％に上昇し，進行胃癌におけるEGJ癌の頻度は1960年代から2000年代で4.0％から8.0％に上昇していた．1990年以降の224例の標本を見直し，BEを有さない食道・胃接合部癌（非BE接合部癌群），short segment BEから発生したと考えられるBE癌（SSBE癌群）およびlong segment BEから発生したと考えられるBE癌（LSBE癌群）の3群に分け，臨床病理学的特徴と担癌胃粘膜の状態をupdated Sydney systemに準じた総合的評価で3群間の比較検討を行った．updated Sydney systemの全項目のスコアは非BE群で有意に高く，早期病変において背景胃粘膜が組織学的に“H. pylori陰性・非萎縮性胃粘膜”と判定されたものは，非BE接合部癌群，SSBE癌群とLSBE癌群でそれぞれ24％，65％，63％であった．H. pyloriの感染率の低下とともに，今後本邦においてもBarrett腺癌を含むEGJ癌は増加する可能性が示唆された．

　To investigate the changing trends of Barrett's adenocarcinoma（BA）and adenocarcinoma of the esophago-gastric junction（EGJ-cancer）in Japan, we studied surgically and endoscopically resected cases in the National Cancer Center Hospital（Tokyo, Japan）between 1962 and 2010. From these cases, the 224 after 1990 were divided into three groups : non-Barrett's esophagus group（non-BE）, SSBE group（SSBE）and LSBE group（LSBE）. The clinicopathological features and histological suggestion of Helicobacter pylori（HP）were also studied. BA among advanced esophageal cancers increased from 0.5％ to 2.8％ from the 1990s through the 2000s and EGJ-cancer among advanced gastric cancers increased from 4.0％ to 8.0％ from the 1960s through the 2000s. According to the Updated Sydney System, we defined histological “HP-negative and non-atrophic gastric mucosa”as mucosa with“chronic inflammation ; 0 or 1, activity ; 0, atrophy ; 0, intestinal metaplasia ; 0 and HP ; 0”. In the early-stage tumors, the rates of the“HP-negative and non-atrophic gastric mucosa”in the non-BE group, the SSBE group, and the LSBE group were 24％, 65％, 63％, respectively. Although the present data do not clearly indicate an increase of BA and EGJ-cancer, the rate of BA and EGJ-cancer could increase with the decline of HP infection rates in the near future in Japan.