長期経過例からみたBarrett粘膜の変化と腺癌の診断

Diagnosis of the Change of Barrett's Epithelium and Adenocarcinoma in the Follow-up Cases

要旨　Barrett食道癌切除例9例の検討では，評価できた8例中6例でp53蛋白過剰発現が認められた．背景となるBarrett上皮は比較的長い傾向があり（平均7.6±3.1cm），癌周辺では9例中8例で腸型上皮が認められた．p53蛋白過剰発現を示すものも2例あった．長期経過例15例の検討では，粘膜の変化として評価できたのは長さのみで，PCNA発現の状態から伸長例において増殖活性が高い可能性が示唆された．またp53蛋白過剰発現陽性例3例中2例が伸長例であった．適切なサーベイランスに必要な各種biomarkerの評価を行うためには，粘膜性状の評価と適切な生検部位の選択が必要である．拡大内視鏡など，新しい観察手段による粘膜評価法について現在検討を進めている．

　Predisposing factors for Barrett's adenocarcinoma were studied in order to determine which patients with Barrett's epithelium should undergo close surveillance.

　In a retrospective study of nine cases of Barrett's adenocarcinoma, most of the cases were positive for p53 protein overexpression, and the associated Barrett's epithelium was relatively long (mean 7.6 ± 3.1 cm). Short segment Barrett's epithelium was found in only one case. The Barrett's epithelium adjacent to the tumor was mostly of the intestinal type, and there were two cases that were positive for p53 protein overexpression.

　Long-term follow-up of 15 cases of Barrett's epithelium was conducted in order to identify endoscopic features which may be predisposing for neoplastic change. Elongation of the Barrett's epithelium was found to correlate with increased PCNA activity and p53 overexpression, although our sample size was small.

　Current endoscopic techniques are inadequate, for identifying mucosal surface changes in Barrett's epithelium that may be predisposing for neoplastic change. Newer techniques, such as use of a magnifying endoscope, need to be developed in order to target the biopsy site and to identify patients that need close surveillance.