薬剤感受性による胃癌化学療法の選択―現状と問題点

Gastric Cancer Chemotherapy Based on Chemosensitivity Test

要旨　本邦における抗癌剤感受性試験の正診率は74％である（第30回制癌剤適応研究会）．われわれは胃癌術後に適応抗癌剤を投与すれば症例の生存期間の延長が図れるのではないかとの仮説をたて，補助化学療法選択における抗癌剤感受性試験の有用性を明らかにしてきた．胃癌補助化学療法については生存期間延長のメリットを受ける適応群とメリットを受けない耐性群が存在し，小規模なRCTによる補助化学療法有用性の証明は困難であり，適応群と耐性群の弁別には現在のところ抗癌剤感受性試験が最も有用と考えられる．抗癌剤感受性試験は標準的治療群を対象としたRCTにより評価される必要があり，現在2つのstudyが検討中である．

　The accuracy of the chemosensitivity test in this country was 74 ％ (30th Annual Meeting of the Japan Research Society for Appropriate Cancer chemotherapy). Based upon the hypothesis, that appropriate adjuvant cancer chemotherapy will increase the survival outcome after surgery of advanced gastric cancer, we have clarified the usefulness of the chemosensitivity test in evaluating the appropriate adjuvant chemotherapy for gastric cancer. Since the gastric cancer cohort includes tumors respondent and non-respondent to adjuvant cancer chemotherapy, a single randomized control trial with small numbers will rarely indicate the usefulness of adjuvant cancer chemotherapy, while plural meta-analyses suggest the usefulness of adjuvant cancer chemotherapy for gastric cancer. The chemosensitivity test will be useful to differentiate the tumors respondent and non-respondent to adjuvant cancer chemotherapy, and two studies are planned to compare the assay-guided therapy and standard therapy after gastric cancer surgery.