食道粘膜下層癌の病態―病理学の立場から

The Lymphnode Metastasis and the Permeation of Vessels, the Tumor Volume of Submucosal Invasion, the Budding and Matrilysin Expression at the Invasive Front in Submucosal Esophageal Carcinoma

要旨　食道sm癌切除例217例（扁平上皮癌，外科手術202例，EMR15例）をsm1，sm2，sm3と細分類して予後と関連する腫瘍組織の全体的な病理学的特徴とsmへ浸潤する腫瘍先進部における組織学的特徴の両者から食道sm癌のリンパ節転移の危険性，予後判断に対する危険因子について検討し，sm1群とsm2，sm3群との間に脈管侵襲陽性率やリンパ節転移率に有意な上昇の差を認めた．リンパ節転移の危険性を示唆する上で病理組織像から脈管侵襲，sm浸潤部の広さ，さらにsm腫瘍先進部における癌胞巣の籏出に加えてmatrilysinの発現が有意の差をもって相関を示し，腫瘍先進部の高度細胞異型も重要な所見とする傾向がみられた．

　Submucosal esophageal carcinomas were divided into three groups according to the degree of submucosal invasion; sm1, sm2 and sms carcinomas. Lymphnode metastasis and prognosis are greatly influenced by the degree of invasion. 217 submucosal carcinomas of the esophagus (202 surgery and 15 EMR cases) were examined histopathologically to evaluate the risk factors connected with lymphnode metastasis. Carcinomas with deeper invasion had a statistically higher incidence of permeation of vessels (p＜0.05). The incidence of permeation of vessels (p＜0.001), the tumor size of the submucosal invasion (p＜0.001) and the incidence of budding at the invasive front (p＜0.05) were significantly correlated to the incidence of lymphnode metastasis. Matrilysin expression at the invasive front in submucosal carcinoma was detected in 55.8% of 77 carcinoma tissues with lymphnode metastasis (p＜0.001). This expression was associated with depth of invasion, lymphnode metastasis and prognosis.

　Our results suggest that the permeation of vessels, the tumor size of submucosal invasion, the budding at the invasive front and matrilysin expression may be useful for the prediction of lymphnode metastasis and poor prognosis.