病理学的所見からみた胃癌の時代的変遷―Helicobacter pylori感染からみて

Clinicopathological Time-trends for Early Gastric Cancer and Helicobacter Pylori Infection

要旨　大阪府立成人病センターで1980～1984年度および20年隔てた2000～2004年度に切除された単発早期胃癌症例の全割標本を臨床病理学的に比較検討した．H. pyloriの有無についても全割HE標本およびギムザ染色標本を用いた鏡検法で検索した．2000～2004年度群では1980～1984年度群に比較して，男性・60歳以上が増加し，肉眼型は隆起型，組織型は高分化腺癌が増加し，逆に潰瘍や潰瘍瘢痕を伴う陥凹型・中分化腺癌・印環細胞癌の減少を認めた．H. pyloriは両群ともに年齢・組織型にかかわらず高率に認められ，組織学的にH. pylori陰性例には萎縮性胃炎が高度な例も多く偽陰性例が含まれる可能性が示唆された．病理組織学的にみた早期胃癌の時代的変遷は日本人の高齢化とH. pylori陽性者年代別分布の変遷によっていると考えられた．

　Comparison was made of the clinicopathological characteristics including Helicobacter pylori infection of 383 and 528 early gastric cancer patients treated in Osaka Medical Center for Cancer and Cardiovascular Diseases over two decades. The ratio of male patients and that of older than 60-year-old patients were found to have significantly increased in the second decade (66％ vs 75％, and 40％ vs 68％, p＜0.01). Grossly, the percentage of elevated-type lesions has significantly increased (22％ vs 37％, p＜0.01), while depressed-with-ulcer or ulcer-scar type has decreased (31％ vs 17％, p＜0.01), and that of tumor smaller-than-30-mm lesions has increased (44％ vs 68％, p＜0.01). Histologically, the percentage of intestinal-type lesions has increased, while mixed and diffuse type have decreased (47％ : 30％ : 23％ vs 64％ : 21％ : 15％, p＜0.01)). The prevalence of H. pylori in both periods was very high (91％ and 95％). Many H. pylori negative patients had severe atrophic gastritis and seemed H. pylori pseudo-negative. These time-trends are thought to reflect the increasing ratio of elderly people in Japanese society, and the decreasing H. pylori positive patients among the younger generation.