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某些卟啉类具有一种在恶性肿瘤中比正常组织中更加集中的天然趋势,这些本身可能相当无害的卟啉类,当暴露于光中时可变得很毒。在光照射下,卟啉富集的肿瘤可被破坏,而含有少量卟啉的周围正常组织仍能存活。经静脉注射卟啉混合物,且暴露于红外线辐照下,可选择性破坏肿瘤,这种新的癌治疗方法现正在被开发。某些卟啉类在恶性肿瘤内所提高的浓度也可用于癌的检查。卟啉以紫光激发会导致红色荧光。当肿瘤和周围组织暴露于紫光时,正常组织只发出较弱的荧光而癌组织却会产生强的红色荧光。这个方法可检查出很小的早期肿瘤。
Certain porphyrins have a natural tendency to be more concentrated in malignant tumors than normal tissues. These may themselves be relatively harmless porphyrins that become very toxic when exposed to light. Under light irradiation, porphyrin-enriched tumors can be destroyed, while surrounding normal tissues containing small amounts of porphyrins can survive. Intravenous injection of porphyrin mixtures and exposure to infrared radiation can selectively destroy tumors. This new cancer treatment is now under development. Increased concentrations of certain porphyrins in malignant tumors can also be used for cancer screening. Excitation of porphyrins with violet light results in red fluorescence. When the tumor and the surrounding tissue are exposed to violet light, normal tissue emits only weaker fluorescence and cancerous tissue produces strong red fluorescence. This method can detect very small early tumors.