Abstract |
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.
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Authors | B W Henderson, T M Busch, L A Vaughan, N P Frawley, D Babich, T A Sosa, J D Zollo, A S Dee, M T Cooper, D A Bellnier, W R Greco, A R Oseroff |
Journal | Cancer research
(Cancer Res)
Vol. 60
Issue 3
Pg. 525-9
(Feb 01 2000)
ISSN: 0008-5472 [Print] United States |
PMID | 10676629
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Antineoplastic Agents
- Dihematoporphyrin Ether
- Oxygen
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Topics |
- Antineoplastic Agents
(therapeutic use)
- Carcinoma, Basal Cell
(drug therapy, metabolism)
- Dihematoporphyrin Ether
(therapeutic use)
- Hematoporphyrin Photoradiation
- Humans
- Oxygen
(metabolism)
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