タキソテール単剤の臨床成績

摘要

切除不能の進行期非小細胞肺癌（non-small cell lung cancer；NSCLC）に対する化学療法はプラチナ製剤と新規抗癌剤の雑み合わせが標準的な治療法と考えられている．新規抗癌剤の中でNSCLCに対して明らかに優れているというレジメンはないが，その中でドセタキセルは2nd-line therapyとしての有効性が示されている．ドセタキセルの未治療NSCLCに対する治療成績は，海外での文献では第二相試験でドセタキセル100mg/m~2，75mg/m~2で治療されており，その奏功率は23-38％でありかつMSTは6.3－14ヶ月であった．それに対し日本での文献では第一相臨床試験の結果を踏まえて，ドセタキセル60mg/m~2で治療されており，奏効率は20％，MSTは10ヶ月であり，海外での成績と比較しやや奏功率でやや劣るもののMSTでは決して引けをとるものではなかった．これらのデータは他の抗癌剤と比較しても遜色なく，今後のNSCLCに対する治療として十分期待しうる結果であった．そこで未治療，既治療NSCLCに対する現在のドセタキセルの治療成績について文献的考察する．Although a meta-analysis and a randomized study have shown that platinum-based chemotherapy yields a survival benefit in first-line treatment of advanced non-small-cell lung cancer (NSCLC), this benefit is only modest. Several new generation drugs (docetaxel, paclitaxel, vmorelbine, gemcitabine, and irinotecan) have demonstrated substantial antitumor activity in a first-line setting. Several phase Ⅱstudies reconsidering the usefulness of second-line therapy were subsequently performed with each new agent. Among such agents, docetaxel yielded the most promising results, with response rates of 16-25%. One Japanese cooperative phase Ⅱstudy in the first-line setting (in Japan docetaxel has been used at a relatively lower dose in both clinical trials and clinical treatment than in European and American countries.) a response rate slightly lower (18.7%) than, but not significantly different from, other phase Ⅱtrials at higher doses. The median survival time (42 weeks) and the severity of neutropenia, dose-limiting tyoxicity of docetaxel, were comparable to those in earlier European and American phase Ⅱtrials. These results suggested that it was reasonable to assess the efficacy and toxicity of low-dose docetaxel (60mg/m~2) for previously treated advanced NSCLC. Thus we consider treatment by docetaxel for advanced NSCLC.