ALA PDT, first approved as a topical therapy to treat precancerous skin lesions in 1999, targets the heme pathway selectively in cancers. When provided with excess ALA, the fluorescent photosensitizer PpIX accumulates primarily in cancer tissue, and ALA PDD is used to identify bladder and brain cancers as a visual aid for surgical resection. ALA PDT has shown promising anecdotal clinical results in recurrent glioblastoma multiforme. ALA SDT represents a noninvasive way to activate ALA PDT and has the potential to achieve clinical success in the treatment of both intracranial and extracranial cancers. This review describes the creation and evolution of ALA PDT, from the treatment of skin cancers to PDD and PDT of malignant brain tumors and, most recently, into a noninvasive form of PDT, ALA SDT. Current clinical trials of ALA SDT for recurrent glioblastoma and high-grade gliomas in adults, and the first pediatric ALA SDT clinical trial for a lethal brainstem cancer, diffuse intrinsic pontine glioma (DIPG), are also described.
ALA PDT于1999年首次获批作为治疗皮肤癌前病变的局部疗法,其作用机制是选择性靶向癌症中的血红素通路。当提供过量ALA时,荧光光敏剂PpIX主要在癌组织中积累,ALA PDD被用于识别膀胱癌和脑癌,作为手术切除的视觉辅助工具。ALA PDT在复发性多形性胶质母细胞瘤中已显示出有希望的临床个案疗效。ALA SDT代表了一种无创激活ALA PDT的方法,有望在治疗颅内和颅外癌症方面取得临床成功。本综述描述了ALA PDT的创建和发展历程,从皮肤癌的治疗到恶性脑肿瘤的PDD和PDT,最近又发展为一种无创形式的PDT——ALA SDT。文中还介绍了目前针对成人复发性胶质母细胞瘤和高级别胶质瘤的ALA SDT临床试验,以及首个针对致命性脑干肿瘤——弥漫性内生性桥脑胶质瘤(DIPG)的儿童ALA SDT临床试验。