Barr H, Dix A J, Kendall C, Stone N
Cranfield Postgraduate Medical School in Gloucestershire, Gloucestershire Royal Hospital, Gloucester, UK.
Aliment Pharmacol Ther. 2001 Mar;15(3):311-21. doi: 10.1046/j.1365-2036.2001.00936.x.
Photodynamic therapy involves the activation of an exogenously administered, or an endogenously generated, photosensitizer with light to produce localized tissue destruction. It is an attractive, predominantly endoscopic technique for the palliation of advanced upper gastrointestinal cancer and the eradication of early neoplastic and pre-neoplastic lesions. The nature of the biological response allowing safe healing and the exploitation of tissue threshold effects mean that adjacent tissue damage can be minimized. This review used a database of 368 papers. The nature of the photosensitizer is critical to the depth of tissue damage and the risk of adjacent tissue damage and stricture formation. The generation of protoporphyrin IX following administration of 5-aminolaevulinic acid has proved useful for the treatment of high-grade dysplasia in Barrett's oesophagus. A double-blind randomized placebo controlled trial has confirmed that it is a safe and effective method for the ablation of low-grade dysplasia. The treatment of more advanced lesions requires exogenously administered photo-sensitizers. However, recent data indicate that the neoplastic potential remains in some patients and continued follow-up is necessary. Photodynamic therapy can be used to eradicate early neoplasia and palliate advanced cancer, but caution is required before a definitive cure can be claimed.
光动力疗法是利用光激活外源性给予或内源性产生的光敏剂，以造成局部组织破坏。它是一种有吸引力的、主要用于内镜的技术，可用于缓解晚期上消化道癌以及根除早期肿瘤性和癌前病变。生物反应的特性使得能够安全愈合并利用组织阈值效应，这意味着可以将相邻组织损伤降至最低。本综述使用了一个包含368篇论文的数据库。光敏剂的性质对于组织损伤的深度、相邻组织损伤和狭窄形成的风险至关重要。给予5-氨基酮戊酸后生成原卟啉IX已被证明对治疗巴雷特食管的高级别异型增生有用。一项双盲随机安慰剂对照试验证实，它是消融低级别异型增生的一种安全有效的方法。治疗更晚期的病变需要外源性给予光敏剂。然而，最近的数据表明，一些患者仍存在肿瘤发生的可能性，因此需要持续随访。光动力疗法可用于根除早期肿瘤并缓解晚期癌症，但在声称能实现根治之前需要谨慎。
