PHOTORADIATION THERAPY OF INDUCED DYSPLASIA

某些有机化学物质和可见光的结合会产生一种 细胞毒作用可能是通过形成单氧来实现的。 血卟啉衍生物(Hpd)是研究最深入的化合物。 产生这种“光动力效应”。暴露于较短波长的 比细胞毒性相关的光线会导致HpD发出荧光。HPD 在肿瘤组织中的滞留程度比正常组织更大 在系统地给药之后。由于该属性， 光动力效应可仅限于肿瘤性病变，但不能 周围的正常组织。这种选择性的细胞毒性已经 在几种动物和人类的肿瘤中都有表现，但还没有 报告为上皮内瘤变。这位恶性肿瘤的光辐射 损害不会受到这种类型的主要限制的影响 治疗中，光线对组织的穿透性差。因为这些损伤是 通常情况下，深度小于4 mm的散射和光能损失不是 这是一个重要因素。一种上皮内瘤变的动物模型已经被 由氨基甲酸酯和十四酰基膦-醋酸酯诱导而成 (TPA)在BDF1小鼠的皮肤中。这些动物将被给予HPD和 暴露在来自Ar离子泵浦的染料激光器的630 nm波长的光中。 将研究选择性光破坏发育不良的病变。 组织学上。从动物研究中收集的信息将用于 设计了一项试验性的人体研究。希望这一点易于管理， 基本上无毒的治疗形式最终可以应用于 人类外阴、阴道和宫颈的癌前病变。 这些部位的上皮内瘤变的光放射治疗 比目前使用的外科手术方式更可取。

The combination of certain organic chemicals and visible light produces a cytotoxic effect probably through the formation of single oxygen. Hematoporphyrin derivative (HPD) is the most thoroughly studied compound producing this "photodynamic effect". Exposure to shorter wavelengths of light than that associated with cytotoxicity causes HPD to fluoresce. HPD is retained in neoplastic tissue to a greater extent than normal tissue following systemic administration. Because of this property the photodynamic effect can be limited to neoplastic lesions with sparing of surrounding normal tissue. This selective cytotoxicity has been demonstrated in several types of animal and human tumors but has not been reported in intraepithelial neoplasia. Photo-radiation of this malignant lesion would not be affected by the main limitation of this type of therapy, poor tissue penetration of light. Since these lesions are typically less than 4 mm in depth scatter and loss of light energy is not a significant factor. An animal model of intraepithelial neoplasia has been developed by induction with urethane and tetradecanoyl-phorbal-acetate (TPA) in the skin of BDF1 mice. These animals will be given HPD and exposed to light of 630 nm wavelength from an argon ion pumped dye laser. Selective photodestruction of dysplastic lesions will be studied histologically. Information collected from animal studies will be used in designing a pilot human study. It is hoped that this easily administered, essentially non-toxic form of therapy can eventually be applied to pre-malignant lesions of the vulva, vagina, and cervix in humans. Photoradiation of intraepithelial neoplasia in these locations would be preferable to currently used surgical modalities.