深達度診断を誤った食道表在癌の検討―X線の立場から

Investigation, from the Standpoint of Radiologic Diagnosis of Misestimation of Invasion Depth of Superficial Esophageal Carcinoma

要旨　食道表在癌切除例（EMR症例を含む）43症例45病変を対象に術前のX線による深達度診断を病理組織所見と対比検討した．正診はm1～m2：4/9，m3～sm1：14/19，sm2～sm3：17/17であったが，誤診例10例中深読みが8例と多くみられた．深読みについては癌の上皮内での肥厚性発育，リンパ濾胞や粘膜下層の線維化が，浅読みについては微小浸潤やinfγが原因として挙げられた．しかし，深達度診断をするのに十分な情報が得られなかった症例が多く，病変を的確に描出したX線画像，特に最深部の正確な側面像が撮影できれば，過半の症例は正診が可能と考えられた．

　We studied 45 lesions (43 cases) of superficial-type esophageal carcinoma under the aspect of radiological diagnosis of the depth of cancerous invasion. Four of 9 lesions in m1-m2, 14 of 19 lesions in m3-sm1, and 17 of 17 lesions in sm2-sm3 were correctly diagnosed. The depth of cancerous invasion in 8 of 10 misdiagnosed lesions were over-estimated. The histopathological causes of over-estimation were thickening growth of the carcinoma within the epithelium and formation of lymphoid follicle in the mucosal or submucosal layers, and fibrosis in the submucosal layer. The causes of under-estimation were minute cancerous invasion and infiltrative carcinoma invasion into the deeper layer of the esophageal wall. However, we might be able to diagnose most of these exactly, if we can get better images of the lesions, especially profile views.

　1) Department of Diagnostic Radiology, School of Medicine, Keio Uiversity, Tokyo