疑似Docetaxel引起的心律不整──案例報告

Docetaxel-associated arrhythmia: a case report

Docetaxel(Taxotere®：20㎎/vial；80㎎/vial)是一種抗腫瘤藥物， 其作用是藉由干擾細胞微小管網狀結構(microtubular network)而達到抗細胞分裂效果。微小管為細胞進行細胞複製時有絲分裂過程及細胞間期所需的重要功能結構。Docetaxel(Taxotere®)會促進微管次體(tubulin)聚合成穩定的微小管(microtubules)，同時Docetaxel(Taxotere®)也會抑制微小管的分離；Docetaxel(Taxotere®)與游離之微管次體結合而使得細胞內微管次體的臨界濃度減少、促成微小管的聚合作用導致生成沒有正常功能的微小管束以及促進微小管的穩定作用，結果造成細胞內有絲分裂的抑制作用。在體外試驗中已發現對多種鼠類及人類腫瘤細胞具有細胞毒性作用，臨床上用來治療乳癌(breast cancer)，非小細胞肺癌(Non-Small Cell Lung cancer)，前列腺癌(prostate cancer)。該藥物的不良反應(adverse effect)表現在：血液學(Hematology)方面－－嗜中性白血球缺乏症（Neutropenia為可逆且無蓄積性的）、貧血（Anemia佔87%，其中10%較嚴重）、噁心、嘔吐、皮膚及四肢局部紅疹，末稍神經毒性：感覺異常，灼熱感，肌肉無力(運動神經不適的症狀)都是可以忍受的，相較於此藥的治療效益，很少比例的人因此類副作用停藥。本文描述一位老年女性患者因肺癌住院接受第二次Docetaxel化療，於冶療過程中發生心律不整的案例。

Docetaxel (Taxotere®) is an antimitotic agent. To achieve its anti-neoplastic effect, docetaxel interferes with the cellular microtubular network, which is necessary for mitosis and maintaining cellular function in interphase. Docetaxel promotes microtubule assembly to form an inappropriately stable, nonfunctional microtubule, and also interferes with the depolymerization of microtubules. Docetaxel acts by binding to free tubulins to decrease the critical concentration of intracellular tubulins. Docetaxel promotes microtubule assembly to form a microtubular ribbon without normal function and stabilizes microtubules by inhibiting depolymerization. This results in inhibition of mitosis [1]. In vitro, docetaxel was found to be cytotoxic in many kinds of rat and human cancer cells. Clinically, it has been used in breast cancer, non-small cell lung cancer and prostate cancer [2]. Haematologic adverse effects of docetaxel include neutropenia (reversible and non-accumulated) and anemia (87%, more serious in 10%). Neurologic adverse events include abnormal feeling, a burning sensation and asthenia which are tolerable adverse events. Due to its beneficial effect, only a few people discontinue this drug due to adverse effects. Other adverse effects such as nausea, vomiting and skin rash have been reported [3]. In this article, we describe a case of docetaxel-associated arrhythmia in an aged female lung cancer patient after secondcycle chemotherapy with docetaxel during hospitalization.