前立腺癌の組織学的分化度と予後の関係 - 前立腺癌取扱い規約分類とGleason分類の比較検討 -

Abstract

前立腺癌ではGSが予後とよく相関するとして欧米で用いられ, 一方, 本邦では1985年に前立腺癌取扱い規約において独自の組織分類法(規約分類)が提唱され, 以下両者を比較した.規約分類とGSはよく相関し, ともに臨床的病期とよく一致した.しかし規約分類における高分化腺癌と中分化腺癌の間, 高分化腺癌と低分化腺癌の間, GS 2-4とGS 5-7の間, GS 2-4とGS 8-10の間では生存率において有意差異がみられた.臨床病期別に規約分類の分化度別癌死率をみると, 各stageにおいて分化度と癌死率の間には直線的な関係がみられた.規約分類をさらに随伴病変の分化度により分類すると, 低分化な成分を含む程に癌死率は高位を示す傾向にあった

To evaluate the correlation between the histological grade and the prognosis, we reviewed 100 cases of prostatic cancer according to the Japanese General Rules of Prostatic Cancer (JGRPC) and Gleason grading system. The study led to the following results: (1) There was a close relation between the JGRPC grade and Gleason score (GS). (2) The JGRPC grade and Gleason score were equally concerned with the clinical stage. (3) There were significant differences in survival rate between well and moderately, well and poorly differentiated groups by the JGRPC grading system, and between GS 2-4 and GS 5-7, GS 2-4 and GS 8-10 groups by Gleason score. (4) In proportion to the JGRPC grade, the cancer death rate increased linearly in each stage. (5) When the patients were grouped according to their JGRPC grades of main lesion and accompanied lesion, the cancer death rate increased in the cases with lower differentiated elements. We conclude that the JGRPC grading system is easily comprehensible, and equal with the Gleason grading system to predict the prognosis of prostatic cancer.