Henderson B W, Busch T M, Vaughan L A, Frawley N P, Babich D, Sosa T A, Zollo J D, Dee A S, Cooper M T, Bellnier D A, Greco W R, Oseroff A R
Photodynamic Therapy Center, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
Cancer Res. 2000 Feb 1;60(3):525-9.
At high fluence rates in animal models, photodynamic therapy (PDT) can photochemically deplete ambient tumor oxygen through the generation of singlet oxygen, causing acute hypoxia and limiting treatment effectiveness. We report that standard clinical treatment conditions (1 mg/kg Photofrin, light at 630 nm and 150 mW/cm2), which are highly effective for treating human basal cell carcinomas, significantly diminished tumor oxygen levels during initial light delivery in a majority of carcinomas. Oxygen depletion could be found during at least 40% of the total light dose, but tumors appeared well oxygenated toward the end of treatment. In contrast, initial light delivery at a lower fluence rate of 30 mW/cm2 increased tumor oxygenation in a majority of carcinomas. Laser treatment caused an intensity- and treatment time-dependent increase in tumor temperature. The data suggest that high fluence rate treatment, although effective, may be inefficient.
在动物模型中，高光通量率下的光动力疗法（PDT）可通过单线态氧的产生光化学耗尽周围肿瘤氧气，导致急性缺氧并限制治疗效果。我们报告称，标准临床治疗条件（1mg/kg 卟吩姆钠、630nm 光照及 150mW/cm²）对治疗人类基底细胞癌非常有效，在大多数癌症的初始光照期间显著降低了肿瘤氧水平。在至少 40%的总光剂量期间可发现氧耗竭，但在治疗结束时肿瘤看起来氧合良好。相比之下，以 30mW/cm²的较低光通量率进行初始光照会使大多数癌症中的肿瘤氧合增加。激光治疗导致肿瘤温度随强度和治疗时间而增加。数据表明，高光通量率治疗虽然有效，但可能效率低下。
