近年来,已知黑素除黑色至暗褐色的铜(Cu)色素外,还存在黄色至红褐色的铬色素系.引人注目的铬色素形成的中间产物——5-S半胱氨酰多巴(5-S-CD)与人种无关,可在正常健康人尿中排泄,按时检测尿中的5-S-CD作为肿瘤标记,对了解恶性黑素瘤的病情有重要意义.测定胸、腹水的5-S-CD亦可作为黑素瘤向胸膜转移的标记. In recent years, melanin has been known to remove yellow to dark brown chromium pigments in addition to black to dark brown copper (Cu) pigments. An attractive intermediate for the formation of chromium pigments, the 5-S cysteinyl Dopa (5-S-CD) has nothing to do with human race, can be excreted in the urine of normal healthy people. On-time detection of 5-S-CD in urine as a tumor marker is important for understanding the condition of malignant melanoma. 5-S-CD in the chest and ascites can also be used as a marker for the metastasis of melanoma to the pleura.