褪黑激素，由松果體分泌的荷爾蒙， 一向被用於調整時差與改善睡眠，雖然在抗老化效果上被媒體過度吹噓，尚無法被列為指示用藥，但卻有直接、間接的實驗證據顯示褪黑激素具有直接調節生長荷爾蒙的功能，並有很強的抗氧化及免疫增強力，可減少及預防癌病的發生或惡化。臨床發現很多癌病患者都有褪黑激素分泌不正常的現象，在補充褪黑激素後，可觀察到腫瘤抑制作用，病患的精神狀況也獲得改善。 與 Tamoxifen 或介白素二號合併治療，除有相輔相成的效果之外，更可降低治療的副作用。本文做了文獻溯閱，並對其機轉做些描述，目的是提醒醫師正視褪黑激素在癌病治療上可能的效果，不要因為坊間的濫用而忽略它真正的價值。

　　　　　Melatonin, an over-exaggerated anti-aging hormone used widely aroundthe world for improving sleep quality, has now shown great potential potentialin fighting against cancers. Many laboratory and clinical evidences support itsoncostatic action, anti-oxidization effect and immune enhancement ability.Cancer patients have altered rhythm of melatonin secretion as compared withhealthy people. Clinical trials provide evidences of improving quality of life,increase disease free survival rates and overall survival rates by supplementwith melatonin in pharmacological dose. Melatonin can reduce the toxicity fromchemotherapy and immunotherapy. It has synergistic effect when combines withInterlukin -2 or tamoxifen. Melatonin may be a newly proposed anti-cancerhormonl for anti-cancer therapy. It should not be overlooked.