食道癌の発育進展―脈管侵襲，リンパ節転移，食道導管内進展を中心に

The Permeation of Vessels, Lymph Node Metastasis and Ductal Involvement in Superficial Esophageal Carcinoma

要旨　食道表在癌68例（m癌：25例，sm癌：43例）で，脈管侵襲（pv），リンパ節転移（n），食道導管内進展（di）について検討した．sm癌では浸潤長を実測し，深達度を分類した．この結果，深達度に応じてpv（＋）率およびn（＋）率の上昇（ρ＜0．01）をみ，n（＋）の有無で生存率に差（p＜O．05）を認めた．diは15例（22.1％）に認め，diからの浸潤は3例と少なく，このうち，1例（6.7％）で深達度が深くなった．di（＋）の有無で生存率には差を認めなかった．以上より，pvとnは癌の進展に伴い増加し，予後を規定する因子であるが，diは粘膜下層への進展の主たる経路ではないと推察された．

　Twenty-five mucosal carcinomas and forty-three submucosal carcinomas of the esophagus were examined histopathologically, to evaluate the incidence of permeation of vessels and lymph node metastasis by the degree of invasion, and the role of ductal involvement in the invasion of carcinoma. Mucosal carcinomas were divided into three groups according to the degree of invasion (m₁ : 3, m₂ : 8, m₃ : 14). Submucosal carcinomas were divided into three groups according to the length of submucosal invasion (sm₁ ; 0 to 1 mm : 11, sm₂ ; 1 to 2 mm : 16, sm₃ ; more than 3 mm : 16). Immunohistochemically, pN0 cases were confirmed. Mucosal carcinoma did not show lymph node metastasis, but three m₃ carcinomas revealed permeation of vessels. Eighteen submucosal carcinomas showed lymph node metastasis (sm₁ : 3, sm₂ : 6, sm₃ : 9). In these cases with lymph node metastasis, the least depth of submucosal invasion was 0.325 mm. Carcinomas with deeper invasion had a statistically higher incidence of the permeation of vessels(p＜0.001) and lymph node metastasis (p ＜ 0.01). Moreover, lymph node metastasis was significantly correlated to the permeation of vessels (p ＜ 0.02) and high-grade atypic of carcinoma cells (p ＜ 0.05). The disease-specific 5-year survival rate of patients with lymph node metastasis was statistically less than that of patients without lymph node metastasis (64.3% vs. 83.2%, p＜ 0.05).

　Fifteen of 68 superficial esophageal carcinomas showed ductal involvement. Three cases with ductal involvement revealed invasion from the ductal involvement, and one of three had deeper depth due to the invasion from ductal involvement.

　In conclusion, esophagectomy with lymphadectomy or radiotherapy might be a suitable treatment for superficial esophageal carcinoma with permeation of vessels or deeper submucosal invasion such as more than 0.3 mm. Ductal involvement might not be the general invasion pathway from mucosa to submucosa in superficial esophageal carcinoma.